Effectiveness of stenting for acute large bowel obstruction

National Guideline Alliance (UK)

Effectiveness of stenting for acute large bowel obstruction

Colorectal cancer (update)

Evidence review C9

NICE Guideline, No. 151

Authors

National Guideline Alliance (UK).

London: National Institute for Health and Care Excellence (NICE); 2020 Jan.

ISBN-13: 978-1-4731-3657-1

Effectiveness of stenting compared with emergency surgery for acute large bowel obstruction

This evidence review supports recommendations 1.3.15 to 1.3.16.

Review question

What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Introduction

Patients presenting with suspected malignant colonic obstruction typically have two treatment options – emergency surgery, which is associated with a number of different complications, including high morbidity and mortality and a high rate of stoma formation; or stenting, which involves placing a hollow, self-expanding, flexible metal tube in the large bowel to keep it open. The use of colonic stents as a bridge to surgery has the potential to convert a bowel obstruction from an emergency condition to an elective situation, yet controversy remains as to whether this treatment option is superior to traditional emergency surgical options. Therefore the aim of this review is to determine the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction.

Summary of the protocol

Please see Table 1 for a summary of the population, intervention, comparison and outcome (PICO) characteristics of this review.

Table 1

Summary of the protocol (PICO table).

For further details see the review protocol in appendix A.

Methods and process

This evidence review was developed using the methods and process described in Developing NICE guidelines: the manual 2014. Methods specific to this review question are described in the review protocol in appendix A.

Declarations of interest were recorded according to NICE’s 2014 conflicts of interest policy until 31 March 2018. From 1 April 2018, declarations of interest were recorded according to NICE’s 2018 conflicts of interest policy. Those interests declared until April 2018 were reclassified according to NICE’s 2018 conflicts of interest policy (see Register of Interests).

Clinical evidence

Included studies

Thirteen RCTs were included in this review (Alcantara 2011; Cheung 2009; Dutch Stent-In-1 trial [Van Hooft 2008]; Dutch Stent-In-2 trial [Van Hooft 2011]; ESCO trial [Arezzo 2017]; Fiori 2004; Ghazal 2013; Ho 2012; Pirlet 2011; Xinopoulos 2004; Young 2015) and 2 follow up studies Cheung 2009 [Tung 2013]; Dutch Stent-In-2 trial [Sloothaak 2014]).

The included studies are summarised in Table 2.

Four trials (Dutch Stent-In-1 trial [Van Hooft 2008]; Fiori 2004; Xinopoulos 2004; Young 2015) compared stent placement with palliative intent to palliative surgery. Seven trials (Alcantara 2011; Cheung 2009; Dutch Stent-In-2 trial [Van Hooft 2011]; ESCO trial [Arezzo 2017]; Ghazal 2013; Ho 2012; Pirlet 2011) compared stent as a bridge to surgery (SBTS) with emergency surgery.

See the literature search strategy in appendix B and study selection flow chart in appendix C.

Expert evidence

The included studies had low numbers of participants and none was carried out in the UK. Three of these trials were stopped early due to excess treatment related adverse events which led some trialists to question the role of stenting in patients due to receive curative surgery. The CReST trial is a UK phase III randomised trial and is larger than any of the trials published to date. The results from CReST were not published within the timeline of the guideline, however results were available and were presented to the guideline committee by one of the CReST trialists as expert witness evidence.

See the summary of expert evidence in appendix M.

Excluded studies

Studies not included in this review with reasons for their exclusions are provided in appendix K.

Summary of clinical studies included in the evidence review

Summaries of the studies that were included in this review are presented in Table 2.

Table 2

Summary of included studies.

See the full evidence tables in appendix D and the forest plots in appendix E.

Quality assessment of clinical outcomes included in the evidence review

See the clinical evidence profiles in appendix F.

Economic evidence

Included studies

A systematic review of the economic literature was conducted but no economic studies were identified which were applicable to this review question.

Excluded studies

A global search of economic evidence was undertaken for all review questions in this guideline. See Supplement 2 for further information.

Economic model

No economic modelling was undertaken for this review because the committee agreed that other topics were higher priorities for economic evaluation.

Evidence statements

Clinical evidence statements

Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery

Critical outcomes

Clinically successful bowel decompression, defined by author (stent arm only)

Palliative intent

Very low quality evidence from 2 RCTs (N=37) showed that clinically successful bowel decompression was achieved in 84% of patients with acute large bowel obstruction undergoing stenting.

Curative intent

Very low quality evidence from 5 RCTs (N=177) showed that clinically successful bowel decompression was achieved in 69% of patients with acute large bowel obstruction undergoing SBTS.

30-day mortality

Palliative intent

Very low quality evidence from 3 RCTs (N=95) showed no clinically important difference in 30-day mortality between receiving stenting compared to emergency surgery for patients with acute large bowel obstruction.

Curative intent

Very low quality evidence from 5 RCTs (N=340) showed no clinically important difference in 30-day mortality between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Disease-free survival

Palliative intent

Not applicable.

Curative intent

Low quality evidence from 2 RCTs (N=106) showed no clinically important difference disease-free survival at 4 to 5 years follow-up between those receiving SBTS and those receiving emergency surgery for patients with acute large bowel obstruction.
Moderate quality evidence from 1 RCT (N=115) showed no clinically important difference in 3-year progression-free survival between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Important outcomes

Overall survival

Palliative intent

Low quality evidence from 1 RCT (N=52) showed no clinically important difference in 1-year overall survival between receiving stenting compared to emergency surgery for patients with acute large bowel obstruction.

Curative intent

Moderate quality evidence from 1 RCT (N=48) showed no clinically important difference in 5-year overall survival between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.
Low quality evidence from 1 RCT (N=58) showed no clinically important difference in 4-year overall survival between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.
Moderate quality evidence from 1 RCT (N=115) showed no clinically important difference in 3-year overall survival between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Length of hospital stay

Palliative intent

Evidence from 2 RCTs (low risk of bias, N=74) showed a clinically important decrease in length of hospital stay (4-5 days less) between receiving stenting compared to emergency surgery for patients with acute large bowel obstruction. However, evidence from 1 RCT (unclear risk of bias, N=21) showed no clinically important decrease in length of hospital stay between receiving stenting compared to emergency surgery for patients with acute large bowel obstruction.

Curative intent

Evidence from 2 RCTs (low risk of bias, N=175) showed a clinically important decrease in length of hospital stay (1-2 days less) between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction. However, evidence from 4 RCTs (high risk of bias, N=196) showed no clinically important decrease in length of hospital stay between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Anastomotic leak

Palliative intent

Low quality evidence from 1 RCT (N=52) showed no clinically important difference in anastomotic leak between receiving stenting compared to emergency surgery for patients with acute large bowel obstruction.

Curative intent

Very low quality evidence from 7 RCTs (N=447) showed no clinically important difference in anastomotic leak between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Perforation rate (stent arm only)

Palliative intent

No evidence was identified for this outcome in this subgroup.

Curative intent

Moderate quality evidence from 3 RCTs (N=133) showed that bowel perforation was experienced in 10% of patients with acute large bowel obstruction undergoing SBTS.

Surgical site infection

Palliative intent

Low quality evidence from 1 RCT (N=52) showed no clinically important difference in surgical site infection between receiving stenting compared to emergency surgery for patients with acute large bowel obstruction.

Curative intent

Very low quality evidence from 6 RCTs (N=387) showed a clinically important decrease in surgical site infection between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Stoma rate

Palliative intent

Low quality evidence from 1 RCT (N=52) showed a clinically important decrease in stoma rate post-procedure between receiving stenting compared to emergency surgery for patients with acute large bowel obstruction.

Curative intent

Moderate quality evidence from 4 RCTs (N=312) showed a clinically important decrease in stoma rate post-procedure between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.
Moderate quality evidence from 4 RCTs (N=300) showed a clinically important decrease in stoma rate at last follow-up between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Technically successful stent placement (stent arm only)

Palliative intent

Very low quality evidence from 3 RCTs (N=52) showed that technical success was achieved in 86% of patients with acute large bowel obstruction undergoing stenting.

Curative intent

Very low quality evidence from 5 RCTs (N=222) showed that technical success was achieved in 69% of patients with acute large bowel obstruction undergoing SBTS.

Stent failure (stent arm only)

Curative intent

Low quality evidence from 2 RCTs (N=76) showed that stent failure was experienced in 18% of patients with acute large bowel obstruction undergoing SBTS.

Overall quality of life

Palliative intent

Low quality evidence from 1 RCT (N=52) showed that while quality of life (measured using EQ-5D) decreased from baseline to 1-year follow-up in both arms, the change was clinically importantly less between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Curative intent

Low quality evidence from 1 RCT (N=98) showed a clinically important increase in quality of life (measured using EORTC-C30 QL2 subscale) from baseline to 6-months between receiving SBTS compared to emergency surgery for patients with acute large bowel obstruction.

Comparison 2: Stenting followed by palliative care versus best supportive care alone

No evidence was identified to inform this comparison.

Expert evidence statements

Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery

Critical outcomes

Clinically successful bowel decompression, defined by author (stent arm only)

Palliative or curative intent

Moderate quality expert evidence indicated clinically successful bowel decompression rates of 82% with stenting.

30-day mortality

Palliative intent

There was no expert evidence on this outcome for this subgroup.

Curative intent

Moderate quality expert evidence indicated no clinically important difference in the 30-day mortality of patients receiving SBTS compared to emergency surgery for acute large bowel obstruction.

Disease-free survival

There was no expert evidence on this outcome.

Important outcomes

Overall survival

Palliative intent

There was no expert evidence on this outcome for this subgroup.

Curative intent

Moderate quality expert evidence indicated no clinically important difference in the overall survival (at 3 years follow-up) of patients receiving SBTS compared to emergency surgery for acute large bowel obstruction.

Length of hospital stay

Palliative intent

Moderate quality expert evidence indicated no clinically important difference in the length of hospital stay for patients receiving SBTS compared to emergency surgery for acute large bowel obstruction.

Curative intent

Moderate quality expert evidence indicated no clinically important difference in the length of hospital stay for patients receiving SBTS compared to emergency surgery for acute large bowel obstruction.

Anastomotic leak

There was no expert evidence on this outcome.

Perforation rate (stent arm only)

Palliative or curative intent

Moderate quality expert evidence indicated that around 5% of patients receiving SBTS experienced perforation, this rate was relatively low compared to previously published trials.

Surgical site infection

There was no expert evidence on this outcome.

Stoma rate

Palliative intent

There was no expert evidence on this outcome for this subgroup.

Curative intent

Moderate quality expert evidence indicated a clinically important reduction in stoma rates for patients receiving SBTS compared to emergency surgery for acute large bowel obstruction.

Stent failure (stent arm only)

There was no expert evidence on this outcome.

Overall quality of life

There was no expert evidence on this outcome.

Economic evidence statements

No economic evidence was identified which was applicable to this review question.

The committee’s discussion of the evidence

Interpreting the evidence

The outcomes that matter most

Clinically successful bowel decompression, as defined by the author, was considered a critical outcome as it identifies the clinical success rate of stent placement compared to emergency surgery. 30-day mortality was also a critical outcome as it indicates the technical success rate of stent deployment. Disease-free survival was a critical outcome for decision making because disease progression suggests ineffective management of the cancer and bowel obstruction, potentially requiring further treatment and affecting overall survival, which was considered an important outcome.

Length of hospital stay and treatment-related morbidity (including anastomotic leak, perforation rate, surgical site infection, stoma rate and stent failure) were considered important outcomes because they are indicators of technical success of the stent. Quality of life was an important outcome because of the impact that different treatment options can have on patients’ functioning and the potential long term adverse effects.

The quality of the evidence

Evidence was available for the comparison of stenting followed by planned bowel resection or palliative care versus emergency surgery. Evidence was available for all of the outcomes. No evidence was available for the comparison of stenting followed by palliative care versus best supportive care alone. The quality of the clinical evidence was assessed using GRADE and varied very low to moderate quality.

The quality was downgraded due to lack of blinding in all trials, and inconsistency or imprecision for some outcomes. Although median length of hospital stay was reported by several studies but it was not possible to pool these results using meta-analysis.

An expert witness presented unpublished results of the CReST trial which provided expert evidence for the comparison of stenting followed by planned bowel resection or palliative care versus emergency surgery. This evidence was assessed using GRADE as moderate quality due to imprecision resulting from the sample size of the trial.

Benefits and harms

The recommendations were based on evidence of reduced stoma rates in patients presenting with acute left-sided large bowel obstruction treated with stents compared with those receiving emergency surgery. There was no evidence of a difference in overall or disease-free survival. Potential harms of stenting included perforation, stent failure or failure to achieve technical success and these patients would then require surgery. The committee agreed that stenting was successful for most patients and so the benefits outweighed the harms. This balance was less clear cut for patients to be treated with curative intent who would go on to receive surgery at some point, and for this group the committee recommended both stenting and emergency surgery as options.

The committee also discussed that stenting allows time to fully assess the patient and stabilise any comorbidities before proceeding with further surgery.

The yet to be published results of the CReST trial were consistent with the published evidence and supported the recommendation for stenting as an option for those suitable for potentially curative resection.

Ideally, the decision about whether to offer stenting or emergency surgery should be taken after discussion with relevant specialists (for example colorectal specialist), however, their unavailability should not delay the timely treatment in an emergency situation.

Cost effectiveness and resource use

A systematic review of the economic literature was conducted but no relevant studies were identified which were applicable to this review question.

These recommendations will lead to an increase in stenting as it is not currently established practice for patients with left-sided large bowel obstruction being treated with palliative intent.

It may also require that patients are transferred to other centres to receive stenting. Stenting however allows patients to be assessed and become stable before surgery reducing operative morbidity and preventing expensive surgery in those individuals where it would not be appropriate. Expert evidence from the CReST trial also highlighted there was a lower rate of stoma. All these would reduce downstream costs and improve quality of life.

References

Alcantara 2011
Alcantara M, Serra-Aracil X, Falco J, et al. (2011) Prospective, controlled, randomized study of intraoperative colonic lavage versus stent placement in obstructive left-sided colonic cancer. World Journal of Surgery 35(8): 1904–1910 [PubMed: 21559998]
Cheung 2009
Cheung H, Chung C, Tsang W, et al. (2009) Endolaparoscopic approach vs conventional open surgery in the treatment of obstructing left-sided colon cancer: a randomized controlled trial. Archives of Surgery 144(12): 1127–32 [PubMed: 20026830]
Tung K, Cheung H, Ng L, et al. (2013) Endo-laparoscopic approach versus conventional open surgery in the treatment of obstructing left-sided colon cancer: long-term follow-up of a randomized trial. Asian journal of Endoscopic Surgery 6(2): 78–81 [PubMed: 23601995]
Dutch Stent-In-1 trial
van Hooft J, Fockens P, Marinelli A, et al. (2008) Early closure of a multicenter randomized clinical trial of endoscopic stenting versus surgery for stage IV left-sided colorectal cancer. Endoscopy 40(3): 184–191 [PubMed: 18322873]
Dutch Stent-In-2 trial
Sloothaak D, van den Berg M Dijkgraaf M, et al. (2014) Oncological outcome of malignant colonic obstruction in the Dutch Stent-In 2 trial. British Journal of Surgery 101(13): 1751–1757 2014 [PubMed: 25298250]
van Hooft J, Bemelman W, Oldenburg B, et al. (2011) Colonic stenting versus emergency surgery for acute left-sided malignant colonic obstruction: A multicentre randomised trial. Lancet Oncology 12(4): 344–352 [PubMed: 21398178]
ESCO trial
Arezzo A, Balague C, Targarona E, et al. (2017) Colonic stenting as a bridge to surgery versus emergency surgery for malignant colonic obstruction: results of a multicentre randomised controlled trial (ESCO trial). Surgical Endoscopy and Other Interventional Techniques 31(8): 3297–3305 [PubMed: 27924392]
Fiori 2004
Fiori E, Lamazza A, De Cesare A, et al. (2004) Palliative management of malignant rectosigmoidal obstruction. Colostomy vs. endoscopic stenting. A randomized prospective trial. Anticancer Research 24(1): 265–268 [PubMed: 15015606]
Ghazal 2013
Ghazal A, El-Shazly W, Bessa S, et al. (2013) Colonic Endolumenal Stenting Devices and Elective Surgery Versus Emergency Subtotal/Total Colectomy in the Management of Malignant Obstructed Left Colon Carcinoma. Journal of Gastrointestinal Surgery 17(6): 1123–1129 [PubMed: 23358847]
Ho 2012
Ho K, Quah H, Lim J, et al. (2011) Emergency preoperative stenting versus surgery for acute left-sided malignant colonic obstruction: a multicenter randomized controlled trial. Surgical Endoscopy 25(6): 1814–1821 [PubMed: 21170659]
Xinopoulos 2004
Xinopoulos D, Dimitroulopoulos D, Theodosopoulos T, et al. (2004) Stenting or stoma creation for patients with inoperable malignant colonic obstructions? Results of a study and cost-effectiveness analysis. Surgical Endoscopy 18(3): 421–426 [PubMed: 14735348]
Young 2015
Young C, De-Loyde K, Young J, (2015) Improving Quality of Life for People with Incurable Large-Bowel Obstruction: Randomized Control Trial of Colonic Stent Insertion. Diseases of the Colon and Rectum 58(9): 838–49 [PubMed: 26252845]

Appendices

Appendix A. Review protocol

Review protocol for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Table 3. Review protocol for pharmacological treatments for spasticity

Appendix B. Literature search strategies

Literature search strategies for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Databases: Embase/Medline

Last searched on: 10/01/2019

Table

Database: Cochrane Library

Last searched on: 10/01/2019

Table

Appendix C. Clinical evidence study selection

Clinical study selection for: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Figure 1. Study selection flow chart

Appendix D. Clinical evidence tables

Clinical evidence tables for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Table 4. Clinical evidence tables (PDF, 721K)

Appendix E. Forest plots

Forest plots for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Figure 2. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - clinically successful bowel decompression - Palliative intent, stent arm only

Figure 3. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - clinically successful bowel decompression – curative intent, stent arm only

Figure 4. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - 30-day mortality – Palliative intent

Figure 5. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - 30-day mortality – Curative intent

Figure 6. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery – disease free survival (follow up 4 to 5 years) – curative intent

Figure 7. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - progression free survival (follow–up 3 years) – Curative intent

Figure 8. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery – overall survival – follow-up 1 to 5 years

Figure 9. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - Anastomotic leak – palliative intent

Figure 10. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - Anastomotic leak – curative intent

Figure 11. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - Perforation rate - Curative intent, stent arm only

Figure 12. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - surgical site infection – palliative intent

Figure 13. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - surgical site infection – curative intent

Figure 14. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - stoma rate

Figure 15. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - technical success – Palliative intent, stent arm only

Figure 16. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery – technical success – Curative intent, stent arm only

Figure 17. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - stent failure – Curative intent, stent arm only

Appendix F. GRADE tables

GRADE tables for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Table 5. Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery

Appendix G. Economic evidence study selection

Economic evidence study selection for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

A global search of economic evidence was undertaken for all review questions in this guideline. See Supplement 2 for further information.

Appendix H. Economic evidence tables

Economic evidence tables for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

No economic evidence was identified which was applicable to this review question.

Appendix I. Economic evidence profiles

Economic evidence profiles for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

No economic evidence was identified which was applicable to this review question.

Appendix J. Economic analysis

Economic evidence analysis for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

No economic analysis was conducted for this review question.

Appendix K. Excluded studies

Excluded clinical studies for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

Table 6. Excluded studies and reasons for their exclusion

Appendix L. Research recommendations

Research recommendations for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?

No research recommendations were made for this review question. 6

Appendix M. Expert evidence

Table 7. Expert evidence for review question: What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction? (PDF, 198K)

Table 8. Gaps addressed and recommendations supported by expert evidence

Table 9. Quality assessment of expert evidence – outcomes in the public domain

Table 10. Quality assessment of expert evidence – redacted outcomes (as yet unpublished)

Final

Evidence reviews

Developed by the National Guideline Alliance part of the Royal College of Obstetricians and Gynaecologists

Disclaimer: The recommendations in this guideline represent the view of NICE, arrived at after careful consideration of the evidence available. When exercising their judgement, professionals are expected to take this guideline fully into account, alongside the individual needs, preferences and values of their patients or service users. The recommendations in this guideline are not mandatory and the guideline does not override the responsibility of healthcare professionals to make decisions appropriate to the circumstances of the individual patient, in consultation with the patient and/or their carer or guardian.

Local commissioners and/or providers have a responsibility to enable the guideline to be applied when individual health professionals and their patients or service users wish to use it. They should do so in the context of local and national priorities for funding and developing services, and in light of their duties to have due regard to the need to eliminate unlawful discrimination, to advance equality of opportunity and to reduce health inequalities. Nothing in this guideline should be interpreted in a way that would be inconsistent with compliance with those duties.

NICE guidelines cover health and care in England. Decisions on how they apply in other UK countries are made by ministers in the Welsh Government, Scottish Government, and Northern Ireland Executive. All NICE guidance is subject to regular review and may be updated or withdrawn.

Bookshelf ID: NBK559925PMID: 32730001

Table 1Summary of the protocol (PICO table)

Population	Adults with acute large bowel obstruction caused by colorectal cancer or suspected colorectal cancer Subgroups: patients treated with curative intent patients treated with palliative intent right versus left sided metastatic versus non-metastatic cancer
Intervention	Stenting followed by planned bowel resection or palliative care
Comparison	Emergency bowel surgery (resection, bypass or stoma) Best supportive care alone
Outcomes	Critical Clinically successful bowel decompression (defined by author) 30-day mortality Disease-free survival Important Overall survival Length of hospital stay Treatment-related morbidity Anastomotic leak Perforation rate Surgical site infection Stoma rate Stent failure (intervention group only) Overall quality of life

: TNM: cancer classification system, standing for tumour, nodal and metastasis stages

Table 2Summary of included studies

Study	Population	Interventions	Outcome	Comments
RCTs in patients treated with palliative intent
Dutch Stent-In-1 trial (Van Hooft 2008) RCT The Netherlands	N= 21 patients over the age of 18 years with incurable, left-sided colorectal cancer with a tumour that was localised between the splenic flexure and the proximal rectum (distal margin at least 10 cm from the anal verge).	Palliative stenting versus palliative surgery	30-day mortality Hospital stay	Terminated early due to high number of serious adverse events in the treatment arm
Fiori 2004 RCT Italy	N= 22 patients with advanced unresectable disease, peritoneal carcinomatosis and/or multiple parenchymatous metastatic disease.	Palliative stenting versus colostomy	Clinically successful bowel decompression 30-day mortality Hospital stay Technically successful stent placement	N/A
Xinopoulos 2004 RCT Greece	N= 30 patients with partial inoperable malignant colonic obstruction	Palliative stenting versus colostomy	Technically successful stent placement	N/A
Young 2015 RCT Australia	N= 52 patients ≥18 years who presented with a malignant large bowel obstruction, deemed not curable by surgical intervention	Palliative stenting versus emergency surgery	Clinically successful bowel decompression 30-day mortality Overall survival Hospital stay Anastomotic leak Surgical site infection Stoma rate Technically successful stent placement	N/A
RCTs in patients treated with curative intent
Alcantara 2011 RCT Spain	N= 28 patients over 18 years of age and a diagnosis of complete intestinal obstruction due to tumour in the left colon using an abdominal CT scan	SBTS versus emergency surgery	30-day mortality Hospital stay Anastomotic leak Surgical site infection Technically successful stent placement	Suspended early due to excess morbidity in emergency surgery group
Cheung 2009; Tung 2013 RCT China	N= 48 patients aged >18 years presenting with clinical features of left colonic obstruction found between the splenic flexure and rectosigmoid junction	SBTS versus emergency surgery	Clinically successful bowel decompression 30-day mortality Disease-free survival Overall survival Hospital stay Anastomotic leak Surgical site infection Stoma rate Technically successful stent placement	N/A
Dutch stent-In-2 trial (Van Hooft 2011; Sloothaak 2014) RCT The Netherlands	N= 98 patients aged ≥18 years, had clinical signs of severe left-sided, colonic obstruction that had existed for less than 1 week, and had dilation of the colon on either plain abdominal radiograph, with typical abnormalities on a gastrografin enema study, or contrast-enhanced CT scan.	SBTS versus emergency surgery	Clinically successful bowel decompression 30-day mortality Disease-free survival Overall survival Anastomotic leak Perforation rate Surgical site infection Stoma rate Technically successful stent placement	N/A
ESCO trial (Arezzo 2017) RCT Italy	N= 115 patients with acute, symptomatic malignant left-sided large-bowel obstruction localised between the splenic flexure and 15 cm from the anal margin, as diagnosed by CT examination in the emergency room	SBTS versus emergency surgery	Clinically successful bowel decompression 30-day mortality Progression-free survival Overall survival Hospital stay Anastomotic leak Perforation rate Surgical site infection Stoma rate Technically successful stent placement Stent failure	N/A
Ghazal 2013 RCT Egypt	N= 60 patients with acute left colonic obstruction confirmed by CT scan of the abdomen	SBTS versus emergency surgery	Hospital stay Anastomotic leak Surgical site infection Technically successful stent placement	N/A
Ho 2012 RCT China	N= 60 patients presenting with acute left colonic obstruction confirmed by a computed tomography of the abdomen	SBTS versus emergency surgery	Clinically successful bowel decompression 30-day mortality Hospital stay Anastomotic leak Surgical site infection Stoma rate Technically successful stent placement Stent failure	N/A
Pirlet 2011 RCT France	N= 60 patients >18 years, fit for both emergency surgery and colonic stenting, and presenting with obstructive symptoms, dilation of the colon, and typical abnormalities confirmed by water-soluble contrast enema, CT scan, or findings at colonoscopy suggesting left-sided malignant obstruction. Tumour located between (including) the splenic flexure and the rectosigmoid junction	SBTS versus emergency surgery	Clinically successful bowel decompression 30-day mortality Hospital stay Anastomotic leak Perforation rate Stoma rate Technically successful stent placement	Suspended early due to bowel perforation in the treatment arm

: CT: computed tomography; N: number; N/A: not applicable; RCT: randomised controlled trial; SBTS: stenting as a bridge to surgery

Table 3Review protocol for pharmacological treatments for spasticity

Field (based on PRISMA-P)	Content
Review question	What is the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction?
Type of review question	Intervention
Objective of the review	To determine the effectiveness of stenting compared with emergency surgery for suspected colorectal cancer causing acute large bowel obstruction.
Eligibility criteria – population/disease/condition/issue/domain	Adults with acute large bowel obstruction caused by colorectal cancer or suspected colorectal cancer Subgroups: patients treated with curative intent patients treated with palliative intent right versus left sided metastatic versus non-metastatic cancer
Eligibility criteria – intervention(s)	Stenting followed by planned bowel resection or palliative care
Eligibility criteria – comparator(s)	Emergency bowel surgery (resection, bypass or stoma) Best supportive care alone
Outcomes and prioritisation	Critical outcomes: Clinically successful bowel decompression (defined by author) (MID: statistical significance) 30-day mortality (MID: statistical significance) Disease-free survival [for the curable group only] (MID: statistical significance) Important outcomes: Overall survival (MID: statistical significance) Length of hospital stay (MID: statistical significance) Treatment-related morbidity (MID: statistical significance) Anastomotic leak Perforation rate Surgical site infection Stoma rate Stent failure (intervention group only) Overall quality of life measured using validated scales (MID: published MIDs from literature) Quality of life MIDs from the literature: EORTC QLQ-C30: 5 points* EORTC QLQ-CR29: 5 points* EORTC QLQ-CR38: 5 points* EQ-5D: 0.09 using FACT-G quintiles FACT-C: 5 points* FACT-G: 5 points* SF-12: > 3.77 for the mental component summary (MCS) and > 3.29 for the physical component summary (PCS) of the Short Form SF-12 (SF-12) SF-36: > 7.1 for the physical functioning scale, > 4.9 for the bodily pain scale, and > 7.2 for the physical component summary *Confirmed with guideline committee.
Eligibility criteria – study design	Systematic reviews of RCTs RCTs If RCT evidence for any of the comparisons is not available systematic reviews of cohort studies and cohort studies will be considered.
Other inclusion exclusion criteria	Inclusion: English-language Published full text papers All settings will be considered that consider medications and treatments available in the UK Studies published post-2000 Studies published 2000 onwards will be considered for this review question because the guideline committee considered that evidence prior to 2000 would not be relevant any longer because the use of stents did not take place prior to this date.
Proposed sensitivity/sub-group analysis, or meta-regression	For observational studies, multivariate analysis should adjust for the following characteristics: Patient characteristics: Age, comorbidities, performance status Tumour characteristics: Location of tumour, severity of bowel obstruction Hospital characteristics: Caseload, tertiary versus secondary In case of high heterogeneity, the following factors will be considered: Treatment characteristics: Type of stent used
Selection process – duplicate screening/selection/analysis	Sifting, data extraction, appraisal of methodological quality and GRADE assessment will be performed by the systematic reviewer. Resolution of any disputes will be with the senior systematic reviewer and the Topic Advisor. Quality control will be performed by the senior systematic reviewer.
Data management (software)	Pairwise meta-analyses will be performed using Cochrane Review Manager (RevMan5). ‘GRADEpro’ will be used to assess the quality of evidence for each outcome. NGA STAR software will be used for study sifting, data extraction, recording quality assessment using checklists and generating bibliographies/citations.
Information sources – databases and dates	Potential sources to be searched (to be confirmed by Information Scientist): Medline, Medline In-Process, CCTR, CDSR, DARE, HTA, Embase Limits (e.g. date, study design): Apply standard animal/non-English language exclusion Limit to RCTs and systematic reviews in first instance, but download all results Dates: post-2000
Identify if an update	Not an update
Author contacts	https://www.nice.org.uk/guidance/indevelopment/gidng10060 Developer: NGA
Highlight if amendment to previous protocol	For details please see section 4.5 of Developing NICE guidelines: the manual
Search strategy – for one database	For details please see appendix B.
Data collection process – forms/duplicate	A standardised evidence table format will be used, and published as appendix D (clinical evidence tables) or H (economic evidence tables).
Data items – define all variables to be collected	For details please see evidence tables in appendix D (clinical evidence tables) or H (economic evidence tables).
Methods for assessing bias at outcome/study level	Standard study checklists were used to critically appraise individual studies. For details please see section 6.2 of Developing NICE guidelines: the manual Appraisal of methodological quality: The methodological quality of each study will be assessed using an appropriate checklist: ROBIS for systematic reviews Cochrane risk of bias tool for RCTs ROBINS-I for non-randomised studies The quality of the evidence for an outcome (i.e. across studies) will be assessed using GRADE. The risk of bias across all available evidence was evaluated for each outcome using an adaptation of the ‘Grading of Recommendations Assessment, Development and Evaluation (GRADE) toolbox’ developed by the international GRADE working group http://www.gradeworkinggroup.org/
Criteria for quantitative synthesis (where suitable)	For details please see section 6.4 of Developing NICE guidelines: the manual
Methods for analysis – combining studies and exploring (in)consistency	Synthesis of data: Pairwise meta-analysis of randomised trials will be conducted where appropriate. When meta-analysing continuous data, final and change scores will be pooled if baselines are comparable. If any studies report both, the method used in the majority of studies will be analysed. Minimally important differences: The guideline committee identified statistically significant differences as appropriate indicators for clinical significance for all outcomes except for quality of life for which published MIDs from literature will be used (see outcomes section for more information).
Meta-bias assessment – publication bias, selective reporting bias	For details please see section 6.2 of Developing NICE guidelines: the manual. If sufficient relevant RCT evidence is available, publication bias will be explored using RevMan software to examine funnel plots.
Assessment of confidence in cumulative evidence	For details please see sections 6.4 and 9.1 of Developing NICE guidelines: the manual
Rationale/context – Current management	For details please see the introduction to the evidence review.
Describe contributions of authors and guarantor	A multidisciplinary committee developed the guideline. The committee was convened by The National Guideline Alliance and chaired by Peter Hoskin in line with section 3 of Developing NICE guidelines: the manual. Staff from The National Guideline Alliance undertook systematic literature searches, appraised the evidence, conducted meta-analysis and cost-effectiveness analysis where appropriate, and drafted the guideline in collaboration with the committee. For details please see Supplement 1: methods.
Sources of funding/support	The National Guideline Alliance is funded by NICE and hosted by the Royal College of Obstetricians and Gynaecologists
Name of sponsor	The National Guideline Alliance is funded by NICE and hosted by the Royal College of Obstetricians and Gynaecologists
Roles of sponsor	NICE funds The National Guideline Alliance to develop guidelines for those working in the NHS, public health, and social care in England
PROSPERO registration number	Not registered

: CCTR: Cochrane Central Register of Controlled Trials; CDSR: Cochrane Database of Systematic Reviews; DARE: Database of Abstracts of Reviews of Effects; EQ-5D: EuroQol five dimensions questionnaire; EORTC QLQ-C30: European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 Items; EORTC QLQ-CR29: European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire colorectal cancer module (29 items); EORTC QLQ-CR38: European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire colorectal cancer module (38 items); FACT-C: Functional Assessment of Cancer Therapy questionnaire (colorectal cancer); FACT-G: Functional Assessment of Cancer Therapy questionnaire (general); GRADE: Grading of Recommendations Assessment, Development and Evaluation; HTA: Health Technology Assessment; MID: minimal important difference; MRI: magnetic resonance imaging; NGA: National Guideline Alliance; NHS: National health service; NICE: National Institute for Health and Care Excellence; PRISMA-P: Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols; PROSPERO: International Prospective Register for Systematic Reviews; RCT: randomised controlled trial; RCT: randomised controlled trial; ROBINS-I: Risk of Bias in Non-randomised Studies – of Interventions; ROBIS: risk of bias in systematic reviews; SD: standard deviation

#	Search
1	(exp colorectal cancer/ or exp colon tumor/ or exp rectum tumor/) use emez
2	exp colorectal neoplasms/ use ppez
3	((colorect* or colo rect* or colon or colonic or rectal or rectum) adj3 (adenocarcinoma* or cancer* or carcinoma* or malignan* or neoplas* or oncolog* or tumo?r*)).tw.
4	or/1-3
5	intestine obstruction/ use emez
6	colon obstruction/ use emez
7	exp intestinal obstruction/ use ppez
8	((bowel or colon or colonic or gastrointestin* or intestine or intestinal) adj4 (obstruct* or block* or occlusion)).tw.
9	((adenocarcinoma* or cancer* or carcinoma* or malignan* or neoplas* or oncolog* or tumo?r) adj4 obstruct).tw.
10	or/5-9
11	stent/ use emez
12	stents/ use ppez
13	stent*.tw.
14	or/11-13
15	4 and 10 and 14
16	remove duplicates from 15
17	limit 16 to (yr=“2000 - current” and english language)
18	Letter/ use ppez
19	letter.pt. or letter/ use emez
20	note.pt.
21	editorial.pt.
22	Editorial/ use ppez
23	News/ use ppez
24	exp Historical Article/ use ppez
25	Anecdotes as Topic/ use ppez
26	Comment/ use ppez
27	Case Report/ use ppez
28	case report/ or case study/ use emez
29	(letter or comment*).ti.
30	or/18-29
31	randomized controlled trial/ use ppez
32	randomized controlled trial/ use emez
33	random*.ti,ab.
34	or/31-33
35	30 not 34
36	animals/ not humans/ use ppez
37	animal/ not human/ use emez
38	nonhuman/ use emez
39	exp Animals, Laboratory/ use ppez
40	exp Animal Experimentation/ use ppez
41	exp Animal Experiment/ use emez
42	exp Experimental Animal/ use emez
43	exp Models, Animal/ use ppez
44	animal model/ use emez
45	exp Rodentia/ use ppez
46	exp Rodent/ use emez
47	(rat or rats or mouse or mice).ti.
48	or/35-47
49	17 not 48

#	Search
1	MeSH descriptor: [Colorectal Neoplasms] explode all trees
2	((colorect* or colo rect* or colon or colonic or rectal or rectum) near/3 (adenocarcinoma* or cancer* or carcinoma* or malignan* or neoplas* or oncolog* or tumor)):ti,ab,kw
3	#1 or #2
4	MeSH descriptor: [Intestinal Obstruction] explode all trees
5	((bowel or colon or colonic or gastrointestin* or intestine or intestinal) near/3 (obstruct* or block* or occlusion)):ti,ab,kw
6	((adenocarcinoma* or cancer* or carcinoma* or malignan* or neoplas* or oncolog* or tumor) near/3 obstruct*):ti,ab,kw
7	#4 or #5 or #6
8	MeSH descriptor: [Stents] this term only
9	(stent*):ti,ab,kw
10	#8 or #9
11	#3 and #7 and #10 with Cochrane Library publication date Between Jan 2000 and Jan 2019

Figure 1Study selection flow chart

Figure 2Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - clinically successful bowel decompression - Palliative intent, stent arm only

RE: random effect

Figure 3Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - clinically successful bowel decompression – curative intent, stent arm only

RE: random effect

Figure 4Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - 30-day mortality – Palliative intent

CI: confidence interval; M-H: Mantel-Haenszel

Figure 5Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - 30-day mortality – Curative intent

CI: confidence interval; M-H: Mantel-Haenszel

Figure 6Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery – disease free survival (follow up 4 to 5 years) – curative intent

CI: confidence interval; IV: inverse variance

Figure 7Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - progression free survival (follow–up 3 years) – Curative intent

CI: confidence interval; IV: inverse variance; SE: standard error

Figure 8Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery – overall survival – follow-up 1 to 5 years

CI: confidence interval; IV: inverse variance; SE: standard error

Figure 9Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - Anastomotic leak – palliative intent

CI: confidence interval; M-H: Mantel-Haenszel

Figure 10Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - Anastomotic leak – curative intent

CI: confidence interval

Figure 11Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - Perforation rate - Curative intent, stent arm only

RE: random effect

Figure 12Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - surgical site infection – palliative intent

CI: confidence interval;

Figure 13Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - surgical site infection – curative intent

CI: confidence interval; M-H: Mantel-Haenszel

Figure 14Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - stoma rate

CI: confidence interval; M-H: Mantel-Haenszel

Figure 15Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - technical success – Palliative intent, stent arm only

RE: random effect

Figure 16Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery – technical success – Curative intent, stent arm only

RE: random effect

Figure 17Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery - stent failure – Curative intent, stent arm only

RE: random effect

Table 5Comparison 1: Stenting followed by planned bowel resection or palliative care versus emergency surgery

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Stenting + planned bowel resection or palliative care	Emergency bowel surgery	Relative (95% CI)	Absolute	Quality	Importance
Clinically successful bowel decompression, stent arm only - Palliative intent
2	randomised trials	no serious risk of bias	serious inconsistency¹	serious²	serious³	none	30/37 (81.1%)	-	Risk 0.84 (0.43 to 0.97)	840 per 1000 (from 430 to 970)	VERY LOW	CRITICAL
Clinically successful bowel decompression, stent arm only - Curative intent
5	randomised trials	very serious⁴^,⁵	serious inconsistency¹	no serious indirectness	serious³	none	123/177 (69.5%)	-	Risk 0.69 (0.53 to 0.82)	690 per 1000 (from 530 to 820)	VERY LOW	CRITICAL
30-day mortality - Palliative intent
3	randomised trials	serious⁴	serious inconsistency¹	serious²	serious³	none	4/48 (8.3%)	4/47 (8.5%)	RD −0.00 (−0.12 to 0.12)	0 more per 1000 (from 120 fewer to 120 more)	VERY LOW	CRITICAL
30-day mortality - Curative intent
5	randomised trials	very serious⁴^,⁵	no serious inconsistency	no serious indirectness	serious³	none	9/168 (5.4%)	10/172 (5.8%)	Peto OR 0.92 (0.36 to 2.34)	4 fewer per 1000 (from 34 fewer to 63 more)	VERY LOW	CRITICAL
Disease free survival, event is disease recurrence or death from any cause (follow-up 4 to 5 years) - Curative intent
2	randomised trials	serious⁶	no serious inconsistency	no serious indirectness	serious³	none	22/50 (44%)	16/56 (29%)	HR 0.56 (0.29 to 1.06)	At 4 years ES 28.1%^b, SBTS 57.2% (27.4% to 78.6%)	LOW	CRITICAL
3-year progression free survival, event is disease recurrence or relapse or death from any cause – Curative intent
1	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	17/56 (30%)	12/59 (20%)	HR 0.95 (0.45 to 2.01)	At 3 years ES 20.3%^c, SBTS 22% (4.2% to 48.8%)	MODERATE	CRITICAL
1-year overall survival, event is death from any cause - Palliative intent
1	randomised trials	no serious risk of bias	no serious inconsistency	serious²	serious³	none	17/26 (65%)	19/26 (73%)	HR 0.84 (0.44 to 1.6)	At 1 year ES 73.1%^d, stenting 76.8% (60.5% to 87.1%)	LOW	IMPORTANT
5-year overall survival, event is death from any cause - Curative intent
1	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	12/24	16/24	HR 0.51 (0.24 to 1.08)	At 5 years ES 67%^a, SBTS 81.5% (64.9% to 90.8%)	MODERATE	IMPORTANT
4-year overall survival, event is death from any cause - Curative intent
1	randomised trials	serious⁶	no serious inconsistency	no serious indirectness	serious³	none	10/26	10/32	HR 0.72 (0.3 to 1.73)	At 4 years ES 31.3%^b, SBTS 43.3% (13.4% to 70%)	LOW	IMPORTANT
3-year overall survival, event is death from any cause - Curative intent
1	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	18/56	16/59	HR 1.00 (0.51 to 1.96)	At 3 years ES 27.1%^c, SBTS 27.2% (7.7% to 51.4%)	MODERATE	IMPORTANT
Hospital stay - Palliative intent - Fiori 2004
1	randomised trials	serious⁴	no serious inconsistency	no serious indirectness	serious³	none	N=15 Median= 2.6	N=13 Median= 8.1	p<0.0001	-	not assessable⁶	IMPORTANT
Hospital stay - Palliative intent - Dutch Stent-In-1 trial (Van Hooft 2008)
1	randomised trials	serious⁴	no serious inconsistency	no serious indirectness	serious³	none	N=11 Median=12 Range=7-19	N=10 Median=11 Range=6.25-17.25	p=0.46	-	not assessable⁶	IMPORTANT
Hospital stay - Palliative intent - Young 2015
1	randomised trials	no serious risk of bias	no serious inconsistency	serious²	serious³	none	N=26 Median=7 Range=3-12	N=26 Median=11 Range=8-17	p=0.03	-	not assessable⁶	IMPORTANT
Hospital stay - Curative intent - Alcantara 2011
1	randomised trials	very serious⁴^,⁵	no serious inconsistency	no serious indirectness	serious³	none	N=15 Median=13	N=13 Median=10	p=0.105	-	not assessable⁶	IMPORTANT
Hospital stay - Curative intent - Cheung 2009
1	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	N=24 Median=13.5 Range=7-29	N=24 Median=14 Range=7-55	p=0.7	-	not assessable⁶	IMPORTANT
Hospital stay - Curative intent - ESCO trial (Arezzo 2017)
1	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	N=56 Median=10 Range=7-13	N=59 Median=11 Range=8-15	-	-	not assessable⁶	IMPORTANT
Hospital stay - Curative intent - Ghazal 2013
1	randomised trials	serious⁴	no serious inconsistency	no serious indirectness	serious³	none	N=30 Median=13	N=30 Median=8	p=0.102	-	not assessable⁶	IMPORTANT
Hospital stay - Curative intent - Ho 2012
1	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	N=20 Median=6 Range=4-28	N=19 Median=8 Range=6-39	p=0.028	-	not assessable⁶	IMPORTANT
Hospital stay - Curative intent - Pirlet 2011
1	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	N=30 Median=23 Range=9-67	N=30 Median=17 (7-126)	p=0.13	-	not assessable⁶	IMPORTANT
Anastomotic leak - Palliative intent
1	randomised trials	no serious risk of bias	no serious inconsistency	serious²	serious³	none	0/26 (0%)	0/26 (0%)	RD 0.00 (−0.07 to 0.07)	0 more per 1000 (from 7 fewer to 7 more)	LOW	IMPORTANT
Anastomotic leak - Curative intent
7	randomised trials	very serious⁴^,⁵	no serious inconsistency	no serious indirectness	serious³	none	11/221 (5%)	12/226 (5.3%)	Peto OR 0.92 (0.40 to 2.13)	4 fewer per 1000 (from 29 fewer to 49 more)	VERY LOW	IMPORTANT
Perforation rate, stent arm only - Curative intent
3	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	13/133 (9.8%)	-	Risk 0.10 (0.06 to 0.17)	100 per 1000 (from 60 to 170)	MODERATE	IMPORTANT
Surgical site infection - Palliative intent
1	randomised trials	no serious risk of bias	no serious inconsistency	serious²	serious³	none	0/26 (0%)	1/26 (3.8%)	Peto OR 0.14 (0.00 to 6.82)⁷	33 fewer per 1000 (from 38 fewer to 176 more)	LOW	IMPORTANT
Surgical site infection - Curative intent
6	randomised trials	very serious⁴^,⁵	no serious inconsistency	no serious indirectness	serious³	none	14/191 (7.3%)	35/196 (17.9%)	RR 0.4 (0.22 to 0.71)	107 fewer per 1000 (from 52 fewer to 139 fewer)	VERY LOW	IMPORTANT
Stoma rate - Palliative intent - Postprocedure
1	randomised trials	no serious risk of bias	no serious inconsistency	serious²	serious³	none	7/26 (26.9%)	24/26 (92.3%)	RR 0.29 (0.15 to 0.55)	655 fewer per 1000 (from 415 fewer to 785 fewer)	LOW	IMPORTANT
Stoma rate - Curative intent - Postprocedure
4	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	50/153 (32.7%)	84/159 (52.8%)	RR 0.62 (0.48 to 0.81)	201 fewer per 1000 (from 100 fewer to 275 fewer)	MODERATE	IMPORTANT
Stoma rate - Curative intent - At last follow up
4	randomised trials	no serious risk of bias	no serious inconsistency	no serious indirectness	serious³	none	37/147 (25.2%)	57/153 (37.3%)	RR 0.70 (0.51 to 0.94)	112 fewer per 1000 (from 22 fewer to 183 fewer)	MODERATE	IMPORTANT
Technically successful stent placement, stent arm only - Palliative intent
3	randomised trials	serious⁴	serious inconsistency¹	serious²	serious³	none	44/52 (84.6%)	-	Risk 0.86 (0.61 to 0.96)	860 per 1000 (from 610 to 960)	VERY LOW	IMPORTANT
Technically successful stent placement, stent arm only - Curative intent
5	randomised trials	very serious⁴^,⁵	serious inconsistency¹	no serious indirectness	serious³	none	174/222 (78.4%)	-	Risk 0.69 (0.66 to 0.72)	690 per 1000 (from 660 to 720)	VERY LOW	IMPORTANT
Stent failure, stent arm only - Curative intent
2	randomised trials	no serious risk of bias	serious inconsistency¹	no serious indirectness	serious³	none	12/76 (15.8%)	-	Risk 0.18 (0.06 to 0.44)	180 per 1000 (from 60 to 440)	LOW	IMPORTANT
Quality of life - Palliative intent - EQ-5D change score, change from baseline to 1 year (Better indicated by lower values)
1	randomised trials	no serious risk of bias	no serious inconsistency	serious²	serious³	none	26	26	-	MD 0.26 higher (0.05 to 0.47 higher)	LOW	IMPORTANT
Quality of life - Curative intent - EORTC-C30 QL2 subscale, change from baseline to 6-months (Better indicated by lower values)
1	randomised trials	serious⁹	no serious inconsistency	no serious indirectness	serious³	none	36	39	-	MD 10.1 higher (1.87 to 18.33 higher)	LOW	IMPORTANT

: CI: confidence interval; EQ-5D: EuroQol five dimensions questionnaire: ES: emergency surgery; HR: hazard ratio; MD: mean difference: N: number; OR: odds ratio; RD: risk difference; RR: relative risk; SBTS: stenting as a bridge to surgery

1: Quality of evidence downgraded by 1 due to moderate-high heterogeneity (I2 > 40%)

2: Quality of evidence downgraded by 1 due to indirectness of the study population - 6/30 (20%) patients had ovarian cancer (Xinopoulos 2004); 12/52 (23%) patients had non-colorectal cancer primaries (Young 2015)

3: Quality of evidence downgraded by 1 because of imprecision of the effect estimate (< 300 events for dichotomous outcomes or < 400 patients for continuous outcomes)

4: Quality of evidence downgraded by 1 due to failure to report random sequence generation procedure, unclear how attrition was managed, outcomes not pre-specified (Alcantara 2011; Fiori 2004; Ghazal 2013; Xinopoulos 2004)

5: Quality of evidence downgraded by 1 because interim safety analyses and termination procedure not determined a priori (Alcantara 2011)

6: Quality of evidence downgraded by 1 due to 69% attrition from original sample (Dutch Stent-In-2-Trial [Sloothaak 2014])

7: Peto OR used due to zero events in one arm

8: Not calculable because of 0 events in both arms

9: Quality of evidence downgraded by 1 because lack of blinding could have affected quality of life outcomes (Dutch Stent-In-2 trial [Van Hooft 2011])

a: The absolute risk at 5 years in the control group taken from Cheung 2009 (Tung 2013)

b: The absolute risk at 4 years in the control group taken from the Dutch Stent-In-2 trial (Sloothaak 2014)

c: The absolute risk at 3 years in the control group taken from the ESCO trial (Arezzo 2017)

d: The absolute risk at 1 year in the control group taken from the Young 2015

Table 6Excluded studies and reasons for their exclusion

Study	Reason for exclusion
Abelson J. S., Yeo H. L., Mao J., Milsom J. W., Sedrakyan A., Long-term postprocedural outcomes of palliative emergency stenting vs stoma in malignant large-bowel obstruction, JAMA Surgery, 152, 429–435, 2017 [PMC free article: PMC5831448] [PubMed: 28097296]	Cohort study; RCT evidence available
Ahn H. J., Kim S. W., Lee S. W., Lim C. H., Kim J. S., Cho Y. K., Park J. M., Lee I. S., Choi M. G., Long-term outcomes of palliation for unresectable colorectal cancer obstruction in patients with good performance status: endoscopic stent versus surgery, Surgical endoscopy and other interventional techniques, 30, 4765–4775, 2016 [PubMed: 26895922]	Cohort study; RCT evidence available
Allaix M. E., Arezzo A., Balague C., Targarona E. M., Morino M., Esco trial: colonic stent versus emergency surgery in malignant colonic occlusion, an interim report, European surgical research., 45, 210â□□211, 2010	Conference abstract
Allievi N., Ceresoli M., Fugazzola P., Montori G., Coccolini F., Ansaloni L., Endoscopic Stenting as Bridge to Surgery versus Emergency Resection for Left-Sided Malignant Colorectal Obstruction: An Updated Meta-Analysis, International journal of surgical oncology, 2017, 2863272, 2017 [PMC free article: PMC5516723] [PubMed: 28761765]	A systematic review, included studies checked for relevance. All studies individually included in review
Amelung F. J., Burghgraef T. A., Tanis P. J., van Hooft J. E., ter Borg F., Siersema P. D., Bemelman W. A., Consten E. C. J., Critical appraisal of oncological safety of stent as bridge to surgery in left-sided obstructing colon cancer; a systematic review and meta-analysis, Critical Reviews in Oncology/Hematology, 131, 66–75, 2018 [PubMed: 30293707]	A systematic review, included studies checked for relevance.
Amelung F. J., de Beaufort H. W. L., Siersema P. D., Verheijen P. M., Consten E. C. J., Emergency resection versus bridge to surgery with stenting in patients with acute right-sided colonic obstruction: a systematic review focusing on mortality and morbidity rates, International journal of colorectal disease, 30, 1147–1155, 2015 [PubMed: 25935448]	A systematic review, included studies checked for relevance.
Amelung F. J., Draaisma W. A., Consten E. C. J., Siersema P. D., ter Borg F., Self-expandable metal stent placement versus emergency resection for malignant proximal colon obstructions, Surgical Endoscopy and Other Interventional Techniques, 31, 4532–4541, 2017 [PubMed: 28409374]	Prospective cohort study; RCT evidence available
Amelung F. J., Draaisma W. A., Consten E. C. J., Siersema P. D., Ter Borg F. J., A case-matched comparative study of self-expandable metal stent placement and emergency resection in the management of proximal colonic obstructions, Surgical Endoscopy and Other Interventional Techniques, 31 (2 Supplement 1), S362, 2017	Conference abstract
Amelung F. J., ter Borg F., Consten E. C. J., Siersema P. D., Draaisma W. A., Deviating colostomy construction versus stent placement as bridge to surgery for malignant left-sided colonic obstruction, Surgical endoscopy and other interventional techniques, 30, 5345â□□5355, 2016 [PubMed: 27071927]	Prospective cohort study; RCT evidence available
Angenete E., Asplund D., Bergstrom M., Park P. O., Stenting for colorectal cancer obstruction compared to surgery-a study of consecutive patients in a single institution, International journal of colorectal disease, 27, 665â□□670, 2012 [PubMed: 22124678]	Prospective cohort study; RCT evidence available
Arezzo A., Passera R., Lo Secco G., Verra M., Bonino M. A., Targarona E., Morino M., Stent as bridge to surgery for left-sided malignant colonic obstruction reduces adverse events and stoma rate compared with emergency surgery: results of a systematic review and meta-analysis of randomized controlled trials, Gastrointestinal endoscopy, 86, 416–426, 2017 [PubMed: 28392363]	A systematic review, included studies checked for relevance.
Atukorale Y. N., Church J. L., Hoggan B. L., Lambert R. S., Gurgacz S. L., Goodall S., Maddern G. J., Self-Expanding Metallic Stents for the Management of Emergency Malignant Large Bowel Obstruction: a Systematic Review, Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract, 20, 455–462, 2016 [PubMed: 26501483]	A systematic review, included studies checked for relevance.
Baik S. H., Kim N. K., Cho H. W., Lee K. Y., Sohn S. K., Cho C. H., Kim T. I., Kim W. H., Clinical outcomes of metallic stent insertion for obstructive colorectal cancer, Hepato-Gastroenterology, 53, 183–187, 2006 [PubMed: 16608020]	Prospective cohort study; RCT evidence available
Bergstrom M., Stolt R., Cikota P., Ahlen R., Park P. O., Inflammatory response to acute treatment of colonic obstruction due to colorectal malignancy, comparing colonic stenting and surgery, Surgical endoscopy and other interventional techniques, 32 (1 Supplement 1), S207, 2018	Conference abstract; retrospective cohort study
Breitenstein S., Rickenbacher A., Berdajs D., Puhan M., Clavien P. A., Demartines N., Systematic evaluation of surgical strategies for acute malignant left-sided colonic obstruction, British journal of surgery, 94, 1451–1460, 2007 [PubMed: 17968980]	A systematic review, included studies checked for relevance.
Carne P. W. G., Frye J. N. R., Robertson G. M., Frizelle F. A., Stents or open operation for palliation of colorectal cancer: A retrospective, cohort study of perioperative outcome and long-term survival, Diseases of the colon and rectum, 47, 1455–1461, 2004 [PubMed: 15486741]	Retrospective cohort study; RCT evidence available
Cennamo V., Luigiano C., Coccolini F., Fabbri C., Bassi M., De Caro G., Ceroni L., Maimone A., Ravelli P., Ansaloni L., Meta-analysis of randomized trials comparing endoscopic stenting and surgical decompression for colorectal cancer obstruction, International journal of colorectal disease, 28, 855–863, 2013 [PubMed: 23151813]	A systematic review, included studies checked for relevance.
Cennamo V., Luigiano C., Manes G., Zagari R. M., Ansaloni L., Fabbri C., Ceroni L., Catena F., Pinna A. D., Fuccio L., et al.,, Colorectal stenting as a bridge to surgery reduces morbidity and mortality in left-sided malignant obstruction: a predictive risk score-based comparative study, Digestive and liver disease, 44, 508â□□514, 2012 [PubMed: 22265809]	Prospective cohort study; RCT evidence available
Ceresoli M., Allievi N., Coccolini F., Montori G., Fugazzola P., Pisano M., Sartelli M., Catena F., Ansaloni L., Long-term oncologic outcomes of stent as a bridge to surgery versus emergency surgery in malignant left side colonic obstructions: A meta-analysis, Journal of Gastrointestinal Oncology, 8, 867–876, 2017 [PMC free article: PMC5674262] [PubMed: 29184691]	A systematic review, included studies checked for relevance.
Choi J. M., Lee C., Han Y. M., Lee M., Choi Y. H., Jang D. K., Im J. P., Kim S. G., Kim J. S., Jung H. C., Long-term oncologic outcomes of endoscopic stenting as a bridge to surgery for malignant colonic obstruction: Comparison with emergency surgery, Surgical Endoscopy and Other Interventional Techniques, 28, 2649–2655, 2014 [PubMed: 24789126]	Prospective cohort study; RCT evidence available
Cirocchi R., Farinella E., Trastulli S., Desiderio J., Listorti C., Boselli C., Parisi A., Noya G., Sagar J., Safety and efficacy of endoscopic colonic stenting as a bridge to surgery in the management of intestinal obstruction due to left colon and rectal cancer: a systematic review and meta-analysis, Surgical OncologySurg Oncol, 22, 14–21, 2013 [PubMed: 23183301]	A systematic review, included studies checked for relevance.
Consolo P., Giacobbe G., Cintolo M., Tortora A., Fama F., Gioffre-Florio M., Pallio S., Colonic acute malignant obstructions: Effectiveness of self-expanding metallic stent as bridge to surgery, Turkish Journal of Gastroenterology, 28, 40–45, 2017 [PubMed: 28007677]	Retrospective cohort study; RCT evidence available
Crespi-Mir A., Romero-Marcos J. M., de la Llave-Serralvo A., Dolz-Abadia C., Cifuentes-Rodenas J. A., Impact on surgical and oncological results of the use of colonic stents as a bridge to surgery for potentially curable occlusive colorectal neoplasms, Cirugia espanola, 96, 419–428, 2018 [PubMed: 29669684]	Retrospective cohort study; RCT evidence available
Cui J., Zhang J. L., Wang S., Sun Z. Q., Jiang X. L., A preliminary study of stenting followed by laparoscopic surgery for obstructing left-sided colon cancer, Zhonghua wei chang wai ke za zhi [Chinese journal of gastrointestinal surgery], 14, 40â□□43, 2011 [PubMed: 21271379]	Article in Chinese
Currie A., Christmas C., Aldean H., Mobasheri M., Bloom I. T. M., Systematic review of self-expanding stents in the management of benign colorectal obstruction, Colorectal Disease, 16, 239–245, 2014 [PubMed: 24033989]	A systematic review, included studies checked for relevance.
Dastur J. K., Forshaw M. J., Modarai B., Solkar M. M., Raymond T., Parker M. C., Comparison of short-and long-term outcomes following either insertion of self-expanding metallic stents or emergency surgery in malignant large bowel obstruction, Techniques in Coloproctology, 12, 51–55, 2008 [PubMed: 18512013]	Retrospective cohort study; RCT evidence available
De Ceglie A., Filiberti R., Baron T. H., Ceppi M., Conio M., A meta-analysis of endoscopic stenting as bridge to surgery versus emergency surgery for left-sided colorectal cancer obstruction, Critical Reviews in Oncology/Hematology, 88, 387–403, 2013 [PubMed: 23845505]	A systematic review, included studies checked for relevance.
Faragher I. G., Chaitowitz I. M., Stupart D. A., Long-term results of palliative stenting or surgery for incurable obstructing colon cancer, Colorectal disease, 10, 668–672, 2008 [PubMed: 18266885]	Retrospective cohort study; RCT evidence available
Finlayson A., Hulme-Moir M., Palliative colonic stenting: a safe alternative to surgery in stage IV colorectal cancer, ANZ Journal of Surgery, 86, 773–777, 2016 [PubMed: 25143253]	Retrospective cohort study; RCT evidence available
Fiori E., Lamazza A., Schillaci A., Femia S., Demasi E., Decesare A., Sterpetti A. V., Palliative management for patients with subacute obstruction and stage IV unresectable rectosigmoid cancer: Colostomy versus endoscopic stenting: Final results of a prospective randomized trial, American Journal of Surgery, 204, 321–326, 2012 [PubMed: 22575396]	Follow up study of Fiori 2004 (included in review), outcomes not relevant
Flor-Lorente B., Báguena, G., Frasson M., García-Granero A., Cervantes A., Sanchiz V., Peña, A., Espí, A., Esclapez P., García-Granero E., Self-expanding metallic stent as a bridge to surgery in the treatment of left colon cancer obstruction: cost-benefit analysis and oncologic results, Cirugia espanola, 95, 143â□□151, 2017 [PubMed: 28336185]	Prospective cohort study; RCT evidence available
Foo C. C., Poon S. H. T., Chiu R. H. Y., Lam W. Y., Cheung L. C., Law W. L., Is bridge to surgery stenting a safe alternative to emergency surgery in malignant colonic obstruction: a meta-analysis of randomized control trials, Surgical Endoscopy., 2018 [PubMed: 30341649]	A systematic review, included studies checked for relevance.
Formisano V., Di Muria A., Connola G., Cione G., Falco L., De Angelis C. P., Angrisani L., Our experience in the management of obstructing colorectal cancer, Annali italiani di chirurgia, 85, 563–568, 2014 [PubMed: 25711439]	Article in Italian
Frago R., Ramirez E., Millan M., Kreisler E., Del Valle E., Biondo S., Current management of acute malignant large bowel obstruction: A systematic review, American journal of surgery, 207, 127–138, 2014 [PubMed: 24124659]	A systematic review, included studies checked for relevance.
Gianotti L., Tamini N., Nespoli L., Rota M., Bolzonaro E., Frego R., Redaelli A., Antolini L., Ardito A., Nespoli A., Dinelli M., A prospective evaluation of short-term and long-term results from colonic stenting for palliation or as a bridge to elective operation versus immediate surgery for large-bowel obstruction, Surgical endoscopy, 27, 832–42, 2013 [PubMed: 23052501]	Prospective cohort study; RCT evidence available
Gibor U., Perry Z. H., Tirosh D., Netz U., Rosental A., Fich A., Man S., Ariad S., Kirshtein B., Comparison of the long-term oncological outcomes of stent as a bridge to surgery and surgery alone in malignant colonic obstruction, Israel Medical Association Journal, 19, 736–740, 2017 [PubMed: 29235734]	Retrospective cohort study; RCT evidence available
Gorissen K. J., Tuynman J. B., Fryer E., Wang L., Uberoi R., Jones O. M., Cunningham C., Lindsey I., Local recurrence after stenting for obstructing left-sided colonic cancer, British journal of surgery, 100, 1805–1809, 2013 [PubMed: 24227368]	Prospective cohort study; RCT evidence available
Guo M. G., Feng Y., Liu J. Z., Zheng Q., Di J. Z., Wang Y., Fan Y. B., Huang X. Y., Factors associated with mortality risk for malignant colonic obstruction in elderly patients, BMC Gastroenterology, 14 (1) (no pagination), 2014 [PMC free article: PMC3998070] [PubMed: 24735084]	Retrospective cohort study; RCT evidence available
Guo M. G., Feng Y., Zheng Q., Di J. Z., Wang Y., Fan Y. B., Huang X. Y., Comparison of self-expanding metal stents and urgent surgery for left-sided malignant colonic obstruction in elderly patients, Digestive Diseases and Sciences, 56, 2706–2710, 2011 [PubMed: 21442324]	Retrospective cohort study; RCT evidence available
Han J. P., Hong S. J., Kim S. H., Choi J. H., Jung H. J., Cho Y. H., Ko B. M., Lee M. S., Palliative self-expandable metal stents for acute malignant colorectal obstruction: Clinical outcomes and risk factors for complications, Scandinavian Journal of Gastroenterology, 49, 967–973, 2014 [PubMed: 24874189]	Prospective cohort study; comparison not relevant, both arms received stents; RCT evidence available
Hanabata N., Sasaki Y., Kanazawa K., Igarashi S., Hasui K., Shimaya K., Numao H., Munakata M., Fukuda S., A comparative study on efficacy of chemotherapy after endoscopic colonic stenting vs. That after colonic surgery in the management of obstructive colorectal cancer, United European Gastroenterology Journal, 5 (5 Supplement 1), A557, 2017	Conference abstract
Haraguchi N., Ikeda M., Miyake M., Yamada T., Sakakibara Y., Mita E., Doki Y., Mori M., Sekimoto M., Colonic stenting as a bridge to surgery for obstructive colorectal cancer: advantages and disadvantages, Surgery Today, 46, 1310–1317, 2016 [PubMed: 27048552]	Prospective cohort study; RCT evidence available
Horesh N., Dux J. Y., Nadler M., Lang A., Zmora O., Shacham-Shmueli E., Gutman M., Shapiro R., Stenting in malignant colonic obstruction-is it a real therapeutic option?, International journal of colorectal disease, 31, 131–135, 2016 [PubMed: 26315014]	Retrospective cohort study; RCT evidence available
Huang X., Lv B., Zhang S., Meng L., Preoperative Colonic Stents Versus Emergency Surgery for Acute Left-Sided Malignant Colonic Obstruction: A Meta-analysis, Journal of gastrointestinal surgery, 18, 584–591, 2014 [PubMed: 24170606]	A systematic review, included studies checked for relevance.
Kang S. I., Oh H. K., Yoo J. S., Ahn S., Kim M. H., Son I. T., Kim D. W., Kang S. B., Park Y. S., Yoon C. J., Shin R., Heo S. C., Lee I. T., Youk E. G., Kim M. J., Chang T. Y., Park S. C., Sohn D. K., Oh J. H., Park J. W., Ryoo S. B., Jeong S. Y., Park K. J., Oncologic outcomes of preoperative stent insertion first versus immediate surgery for obstructing left-sided colorectal cancer, Surgical Oncology, 27, 216–224, 2018 [PubMed: 29937174]	Retrospective cohort study; RCT evidence available
Karoui M., Charachon A., Delbaldo C., Loriau J., Laurent A., Sobhani I., Tran Van Nhieu J., Delchier J. C., Fagniez P. L., Piedbois P., Cherqui D., Stents for palliation of obstructive metastatic colon cancer: Impact on management and chemotherapy administration, Archives of Surgery, 142, 619–623, 2007 [PubMed: 17638798]	Retrospective cohort study; RCT evidence available
Karoui M., Soprani A., Charachon A., Delbaldo C., Vigano L., Luciani A., Cherqui D., Primary chemotherapy with or without colonic stent for management of irresectable stage IV colorectal cancer, European Journal of Surgical Oncology, 36, 58–64, 2010 [PubMed: 19926243]	Prospective cohort study; RCT evidence available
Kavanagh D. O., Nolan B., Judge C., Hyland J. M. P., Mulcahy H. E., O’Connell P. R., Winter D. C., Doherty G. A., A comparative study of short- and medium-term outcomes comparing emergent surgery and stenting as a bridge to surgery in patients with acute malignant colonic obstruction, Diseases of the colon and rectum, 56, 433–440, 2013 [PubMed: 23478610]	Retrospective cohort study; RCT evidence available
Khot U. P., Wenk Lang A., Murali K., Parker M. C., Systematic review of the efficacy and safety of colorectal stents, British journal of surgery, 89, 1096–1102, 2002 [PubMed: 12190673]	A systematic review, included studies checked for relevance.
Kim H. H., Kim H. K., Cho S. H., Huh J. W., Rhyu S. Y., Kim H. R., Kim D. Y., Kim Y. J., Ju J. K., Usefulness of self-expandable metallic stents for malignant colon obstruction, Journal of the Korean Society of Coloproctology, 25, 113–116, 2009	Unavailable from the British Library
Kim H. J., Choi G. S., Park J. S., Park S. Y., Jun S. H., Higher rate of perineural invasion in stent-laparoscopic approach in comparison to emergent open resection for obstructing left-sided colon cancer, International journal of colorectal disease, 28, 407â□□414, 2013 [PubMed: 22885839]	Prospective cohort study; RCT evidence available
Kim H. J., Huh J. W., Kang W. S., Kim C. H., Lim S. W., Joo Y. E., Kim H. R., Kim Y. J., Oncologic safety of stent as bridge to surgery compared to emergency radical surgery for left-sided colorectal cancer obstruction, Surgical Endoscopy and Other Interventional Techniques, 27, 3121–3128, 2013 [PubMed: 23436100]	Retrospective cohort study; RCT evidence available
Kim J. S., Hur H., Min B. S., Sohn S. K., Cho C. H., Kim N. K., Oncologic outcomes of self-expanding metallic stent insertion as a bridge to surgery in the management of left-sided colon cancer obstruction: Comparison with nonobstructing elective surgery, World journal of surgery, 33, 1281–1286, 2009 [PubMed: 19363580]	Prospective cohort study; RCT evidence available
Kim M. K., Kye B. H., Lee I. K., Oh S. T., Ahn C. H., Lee Y. S., Lee S. C., Kang W. K., Outcome of bridge to surgery stenting for obstructive left colon cancer, ANZ Journal of Surgery, 87, E245–E250, 2017 [PubMed: 27061756]	Retrospective cohort study; RCT evidence available
Kim S. J., Kim H. W., Park S. B., Kang D. H., Choi C. W., Song B. J., Hong J. B., Kim D. J., Park B. S., Son G. M., Colonic perforation either during or after stent insertion as a bridge to surgery for malignant colorectal obstruction increases the risk of peritoneal seeding, Surgical endoscopy and other interventional techniques, 29, 3499–3506, 2015 [PubMed: 25676202]	Retrospective cohort study; RCT evidence available
Knight A. L., Trompetas V., Saunders M. P., Anderson H. J., Does stenting of left-sided colorectal cancer as a “bridge to surgery” adversely affect oncological outcomes A comparison with non-obstructing elective left-sided colonic resections, International journal of colorectal disease, 27, 1509–1514, 2012 [PubMed: 22684548]	Retrospective cohort study; RCT evidence available
Kwak M. S., Kim W. S., Lee J. M., Yang D. H., Yoon Y. S., Yu C. S., Kim J. C., Byeon J. S., Does Stenting as a Bridge to Surgery in Left-Sided Colorectal Cancer Obstruction Really Worsen Oncological Outcomes?, Diseases of the colon and rectum, 59, 725–732, 2016 [PubMed: 27384090]	Retrospective cohort study; RCT evidence available
Lamazza A., Fiori E., Schillaci A., DeMasi E., Pontone S., Sterpetti A. V., Self-expandable metallic stents in patients with stage IV obstructing colorectal cancer, World journal of surgery, 36, 2931–2936, 2012 [PubMed: 22960673]	A systematic review, included studies checked for relevance.
Law W. L., Choi H. K., Chu K. W., Comparison of stenting with emergency surgery as palliative treatment for obstructing primary left-sided colorectal cancer, British Journal of Surgery, 90, 1429–33, 2003 [PubMed: 14598426]	Prospective cohort study; RCT evidence available
Lee G. J., Kim H. J., Baek J. H., Lee W. S., Kwon K. A., Comparison of short-term outcomes after elective surgery following endoscopic stent insertion and emergency surgery for obstructive colorectal cancer, International Journal of Surgery, 11, 442–6, 2013 [PubMed: 23639803]	Retrospective cohort study; RCT evidence available
Lee H. J., Hong S. P., Cheon J. H., Kim T. I., Min B. S., Kim N. K., Kim W. H., Long-term outcome of palliative therapy for malignant colorectal obstruction in patients with unresectable metastatic colorectal cancers: Endoscopic stenting versus surgery, Gastrointestinal Endoscopy, 73, 535–542, 2011 [PubMed: 21257165]	Retrospective cohort study; RCT evidence available
Lee W. S., Baek J. H., Kang J. M., Choi S., Kwon K. A., The outcome after stent placement or surgery as the initial treatment for obstructive primary tumor in patients with stage IV colon cancer, American Journal of Surgery, 203, 715–719, 2012 [PubMed: 22265203]	Retrospective cohort study; RCT evidence available
Li Z. X., Wu X. H., Wu H. Y., Chang W. J., Chang X. J., Yi T., Shi Q., Chen J. W., Feng Q. Y., Zhu D. X., Wei Y., Zhong Y. S., Xu J. M., Self-expandable metallic stent as a bridge to elective surgery versus emergency surgery for acute malignant colorectal obstruction, International journal of colorectal disease, 31, 561–570, 2016 [PubMed: 26700099]	Retrospective cohort study; RCT evidence available
Liang T. W., Sun Y., Wei Y. C., Yang D. X., Palliative treatment of malignant colorectal obstruction caused by advanced malignancy: A self-expanding metallic stent or surgery? A system review and meta-analysis, Surgery Today, 44, 22–33, 2014 [PubMed: 23893158]	A systematic review, included studies checked for relevance.
Lim T. Z., Chan D. K. H., Tan K. K., Endoscopic stenting should be advocated in patients with stage IV colorectal cancer presenting with acute obstruction, Journal of Gastrointestinal Oncology, 9, 785–790, 2018 [PMC free article: PMC6219967] [PubMed: 30505576]	Retrospective cohort study; RCT evidence available
Lim T. Z., Chan D., Tan K. K., Patients who failed endoscopic stenting for left-sided malignant colorectal obstruction suffered the worst outcomes, International Journal of Colorectal Disease., 02, 2014 [PubMed: 24986142]	Retrospective cohort study; RCT evidence available
Liu Z., Kang L., Li C., Huang M., Zhang X., Wang J., Meta-analysis of complications of colonic stenting versus emergency surgery for acute left-sided malignant colonic obstruction, Surgical Laparoscopy, Endoscopy and Percutaneous Techniques, 24, 73–79, 2014 [PubMed: 24487162]	A systematic review, included studies checked for relevance.
Mabardy A., Miller P., Goldstein R., Coury J., Hackford A., Dao H., Stenting for obstructing colon cancer: fewer complications and colostomies, JSLS : Journal of the Society of Laparoendoscopic Surgeons, 19, e2014.00254, 2015 [PMC free article: PMC4379870] [PubMed: 25848200]	Retrospective cohort study; RCT evidence available
Martinez-Santos C., Lobato R. F., Fradejas J. M., Pinto I., Ortega-Deballon P., Moreno-Azcoita M., Self-expandable stent before elective surgery vs. emergency surgery for the treatment of malignant colorectal obstructions: Comparison of primary anastomosis and morbidity rates, Diseases of the colon and rectum, 45, 401–406, 2002 [PubMed: 12068202]	Prospective cohort study; RCT evidence available
Morita S., Yamamoto K., Ogawa A., Naito A., Mizuno H., Yoshioka S., Matsumura T., Ohta K., Suzuki R., Matsuda C., Hata T., Nishimura J., Mizushima T., Doki Y., Mori M., Miyake M., Miyoshi N., Tamagawa H., Ohta H., Nushijima Y., Danno K., Takemoto H., Fumimoto Y., Ohashi I., Benefits of using a self-expandable metallic stent as a bridge to surgery for right- and left-sided obstructive colorectal cancers, Surgery Today, 49, 32–37, 2019 [PubMed: 30105529]	Retrospective cohort study; RCT evidence available
Nagula S., Ishill N., Nash C., Markowitz A. J., Schattner M. A., Temple L., Weiser M. R., Thaler H. T., Zauber A., Gerdes H., Quality of Life and Symptom Control after Stent Placement or Surgical Palliation of Malignant Colorectal Obstruction, Journal of the American College of Surgeons, 210, 45–53, 2010 [PubMed: 20123331]	Prospective cohort study; RCT evidence available
Ng K. C., Law W. L., Lee Y. M., Choi H. K., Seto C. L., Ho J. W. C., Self-Expanding Metallic Stent as a Bridge to Surgery Versus Emergency Resection for Obstructing Left-Sided Colorectal Cancer: A Case-Matched Study, Journal of gastrointestinal surgery, 10, 798–803, 2006 [PubMed: 16769535]	Prospective cohort study; RCT evidence available
Olson T. J. P., Pinkerton C., Brasel K. J., Schwarze M. L., Palliative surgery for malignant bowel obstruction from carcinomatosis a systematic review, JAMA Surgery, 149, 383–392, 2014 [PMC free article: PMC4030748] [PubMed: 24477929]	A systematic review, included studies checked for relevance.
Park J., Lee H. J., Park S. J., Hur H., Min B. S., Cheon J. H., Kim T. I., Kim N. K., Kim W. H., Long-term outcomes after stenting as a bridge to surgery in patients with obstructing left-sided colorectal cancer, International journal of colorectal disease, 33, 799–807, 2018 [PubMed: 29532209]	Retrospective cohort study; RCT evidence available
Poultsides G. A., Servais E. L., Saltz L. B., Patil S., Kemeny N. E., Guillem J. G., Weiser M., Temple L. K. F., Wong W. D., Paty P. B., Outcome of primary tumor in patients with synchronous stage IV colorectal cancer receiving combination chemotherapy without surgery as initial treatment, Journal of Clinical OncologyJ Clin Oncol, 27, 3379–3384, 2009 [PMC free article: PMC3646319] [PubMed: 19487380]	Retrospective cohort study; RCT evidence available
Ptok H., Marusch F., Steinert R., Meyer L., Lippert H., Gastinger I., Incurable stenosing colorectal carcinoma: Endoscopic stent implantation or palliative surgery?, World journal of surgery, 30, 1481–1487, 2006 [PubMed: 16850152]	Prospective cohort study; RCT evidence available
Quereshy F. A., Poon J. T. C., Law W. L., Long-term outcome of stenting as a bridge to surgery for acute left-sided malignant colonic obstruction, Colorectal disease, 16, 788–793, 2014 [PubMed: 24836397]	Retrospective cohort study; RCT evidence available
Rees J., Tanner J., Patel P., Trudgill N., The outcomes of self-expanding metal stents as a bridge to curative resection in patients with colorectal cancer presenting with bowel obstruction, United European Gastroenterology Journal, 4 (5 Supplement 1), A664, 2016	Conference abstract
Ribeiro I. B., Bernardo W. M., Martins B. D. C., de Moura D. T. H., Baba E. R., Josino I. R., Miyahima N. T., Coronel Cordero M. A., Visconti T. A. C., Ide E., Sakai P., de Moura E. G. H., Colonic stent versus emergency surgery as treatment of malignant colonic obstruction in the palliative setting: a systematic review and meta-analysis, Endoscopy International Open, 6, E558–E567, 2018 [PMC free article: PMC5943694] [PubMed: 29756013]	A systematic review, included studies checked for relevance.
Ribeiro I., Pinho R., Leite M., Proenca L., Silva J., Ponte A., Rodrigues J., Maciel-Barbosa J., Carvalho J., Reevaluation of Self-Expanding Metal Stents as a Bridge to Surgery for Acute Left-Sided Malignant Colonic Obstruction: Six Years Experience, Portuguese Journal of Gastroenterology, 23, 76–83, 2016 [PMC free article: PMC5580145] [PubMed: 28868437]	Retrospective cohort study; RCT evidence available
Rodrigues-Pinto E., Morais R., Coelho C., Pereira P., Repici A., Macedo G., Bridge-to-surgery versus emergency surgery in the management of left-sided acute malignant colorectal obstruction - Efficacy, safety and long-term outcomes, Digestive and Liver Disease., 2018 [PubMed: 30558864]	Retrospective cohort study; RCT evidence available
Sagar J., Colorectal stents for the management of malignant colonic obstructions, Cochrane Database of Systematic Reviews, 2011 [PMC free article: PMC6885054] [PubMed: 22071835]	Systematic review - studies assessed individually
Saida Y., Sumiyama Y., Nagao J., Uramatsu M., Long-term prognosis of preoperative “bridge to surgery” expandable metallic stent insertion for obstructive colorectal cancer: Comparison with emergency operation, Diseases of the colon and rectum, 46, S44–S49, 2003 [PubMed: 14530657]	Retrospective cohort study; RCT evidence available
Sebastian S., Johnston S., Geoghegan T., Torreggiani W., Buckley M., Pooled analysis of the efficacy and safety of self-expanding metal stenting in malignant colorectal obstruction, American journal of gastroenterology, 99, 2051–2057, 2004 [PubMed: 15447772]	A systematic review, included studies checked for relevance
Siddiqui A., Cosgrove N., Yan L. H., Brandt D., Janowski R., Kalra A., Zhan T., Baron T. H., Repici A., Taylor L. J., Adler D. G., Long-term outcomes of palliative colonic stenting versus emergency surgery for acute proximal malignant colonic obstruction: a multicenter trial, Endoscopy International Open, 5, E232–E238, 2017 [PMC free article: PMC5362371] [PubMed: 28367495]	Retrospective cohort study; RCT evidence available
Sloothaak D. A., Van Den Berg M. W., Dijkgraaf M. G., Fockens P., Tanis P. J., Van Hooft J. E., Bemelman W. A., Oncological follow up of the stent-in 2 trial: Cancer recurrence after curative treatment of malignant colonic obstruction, Gastrointestinal Endoscopy, Conference, Digestive Diease Week, DDW 2014 ASGE. Chicago, IL United States. Conference Publication: (var.pagings). 79 (5 SUPPL. 1) (pp AB161), 2014	Conference abstract
Takahashi H., Okabayashi K., Tsuruta M., Hasegawa H., Yahagi M., Kitagawa Y., Self-Expanding Metallic Stents Versus Surgical Intervention as Palliative Therapy for Obstructive Colorectal Cancer: A Meta-analysis, World journal of surgery, 39, 2037–2044, 2015 [PubMed: 25894403]	A systematic review, included studies checked for relevance
Tan C. J., Dasari B. V. M., Gardiner K., Systematic review and meta-analysis of randomized clinical trials of self-expanding metallic stents as a bridge to surgery versus emergency surgery for malignant left-sided large bowel obstruction, British journal of surgery, 99, 469–476, 2012 [PubMed: 22261931]	A systematic review, included studies checked for relevance
Targownik L. E., Spiegel B. M., Sack J., Hines O. J., Dulai G. S., Gralnek I. M., Farrell J. J., Colonic stent vs. emergency surgery for management of acute left-sided malignant colonic obstruction: A decision analysis, Gastrointestinal endoscopy, 60, 865–874, 2004 [PubMed: 15604999]	Cost analysis
Tilney H. S., Lovegrove R. E., Purkayastha S., Sains P. S., Weston-Petrides G. K., Darzi A. W., Tekkis P. P., Heriot A. G., Comparison of colonic stenting and open surgery for malignant large bowel obstruction, Surgical endoscopy and other interventional techniques, 21, 225–233, 2007 [PubMed: 17160651]	A systematic review, included studies checked for relevance
Tomiki Y., Watanabe T., Ishibiki Y., Tanaka M., Suda S., Yamamoto T., Sakamoto K., Kamano T., Comparison of stent placement and colostomy as palliative treatment for inoperable malignant colorectal obstruction, Surgical endoscopy and other interventional techniques, 18, 1572–1577, 2004 [PubMed: 15931483]	Prospective cohort study; RCT evidence available
Tominaga H., Shimizu Y., Yamashita S., Odagiri K., Kurokawa T., Honmyo N., Moon J., Inoue M., Irei T., Tanemura M., et al.,, Feasibility and safety of laparoscopic resection following stent insertion for obstructing colon cancer, Surgical endoscopy and other interventional techniques., 29, S165, 2015	Conference abstract
Van Den Berg M. W., Sloothaak D. A. M., Dijkgraaf M. G. W., Van Der Zaag E. S., Bemelman W. A., Tanis P. J., Bosker R. J. I., Fockens P., Ter Borg F., Van Hooft J. E., Bridge-to-surgery stent placement versus emergency surgery for acute malignant colonic obstruction, British journal of surgery, 101, 867–873, 2014 [PubMed: 24740753]	Retrospective cohort study; RCT evidence available
van Hooft J. E., Bemelman W. A., Breumelhof R., Siersema P. D., Kruyt P. M., van der Linde K., Veenendaal R. A., Verhulst M. L., Marinelli A. W., Gerritsen J. J., et al.,, Colonic stenting as bridge to surgery versus emergency surgery for management of acute leftsided malignant colonic obstruction: a multicenter randomized trial (Stent-in 2 study), BMC surgery, 7, 12, 2007 [PMC free article: PMC1925059] [PubMed: 17608947]	Protocol
Vemulapalli R., Lara L. F., Sreenarasimhaiah J., Harford W. V., Siddiqui A. A., A comparison of palliative stenting or emergent surgery for obstructing incurable colon cancer, Digestive Diseases and Sciences, 55, 1732–1737, 2010 [PubMed: 19693667]	Retrospective cohort study; RCT evidence available
Vitale M. A., Villotti G., d’Alba L., Frontespezi S., Iacopini F., Iacopini G., Preoperative colonoscopy after self-expandable metallic stent placement in patients with acute neoplastic colon obstruction, Gastrointestinal endoscopy, 63, 814–819, 2006 [PubMed: 16650544]	Prospective cohort study; RCT evidence available
Wang X., He J., Chen X., Yang Q., Stenting as a bridge to resection versus emergency surgery for left-sided colorectal cancer with malignant obstruction: A systematic review and meta-analysis, International Journal of Surgery, 48, 64–68, 2017 [PubMed: 29024743]	A systematic review, included studies checked for relevance
White S. I., Abdool S. I., Frenkiel B., Braun W. V., Management of malignant left-sided large bowel obstruction: A comparison between colonic stents and surgery, ANZ Journal of Surgery, 81, 257–260, 2011 [PubMed: 21418469]	Retrospective cohort study; RCT evidence available
Yan F. H., Lou Z., Liu X. S., Wang Z., Xu X. D., Gao Y. J. Y., He J., Wang H., Fu C. G., Zhang W., He H. Y., Cai B. L., Yu E. D., Long-Term Oncological Outcomes of Endoscopic Stenting as a Bridge to Surgery Versus Emergency Surgery for Malignant Colorectal Obstruction: A Comparative Study, Journal of Laparoendoscopic and Advanced Surgical Techniques, 27, 611–617, 2017 [PubMed: 28092477]	Prospective cohort study; RCT evidence available
Yang P., Lin X. F., Lin K., Li W., The Role of Stents as Bridge to Surgery for Acute Left-Sided Obstructive Colorectal Cancer: Meta-Analysis of Randomized Controlled Trials, Revista de investigacion clinica; organo del Hospital de Enfermedades de la Nutricion, 70, 269–278, 2018 [PubMed: 30532112]	A systematic review, included studies checked for relevance
Ye G. Y., Cui Z., Chen L., Zhong M., Colonic stenting vs emergent surgery for acute left-sided malignant colonic obstruction: A systematic review and meta-analysis, World Journal of Gastroenterology, 18, 5608–5615, 2012 [PMC free article: PMC3482649] [PubMed: 23112555]	A systematic review, included studies checked for relevance
Yoon J. Y., Park S. J., Hong S. P., Kim T. I., Kim W. H., Cheon J. H., Outcomes of secondary self-expandable metal stents versus surgery after delayed initial palliative stent failure in malignant colorectal obstruction, Digestion, 88, 46–55, 2013 [PubMed: 23880524]	Retrospective cohort study; RCT evidence available
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: RCT: randomised controlled trial

Table 8Gaps addressed and recommendations supported by expert evidence

Expert evidence	Gaps addressed	Recommendations supported
Preliminary findings from the CReST trial	The published evidence base relies on 13 small RCTs (none from the UK). Three of these trials were stopped early due to excess treatment related adverse events which led some trialists to question the role of stenting in patients due to receive curative surgery. The CReST trial is a UK Phase III randomised trial and is larger than any of the trials published to date. The results from CReST have not yet been published and the timeline of the guideline does not allow us to wait for the results to be published later this year.	1.3.15 1.3.16

: CReST: ColoRectal endoscopic Stenting Trial

Table 9Quality assessment of expert evidence – outcomes in the public domain⁴

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Stenting + planned bowel resection or palliative care	Emergency bowel surgery	Relative (95% CI)	Absolute	Quality	Importance
Clinically successful bowel decompression, stent arm only – Palliative or curative intent
1	randomised trials	no serious risk of bias¹	no serious inconsistency	no serious indirectness	serious²	none	98/119⁴ (82%)	-	-	-	MODERATE	CRITICAL
Perforation rate, stent arm only – Palliative or curative intent
3	randomised trials	no serious risk of bias¹	no serious inconsistency	no serious indirectness	serious²	none	6/123⁴ (5%)	-	Risk 0.05	50 more per 1000	MODERATE	IMPORTANT
Stoma rate - Curative intent
1	randomised trials	no serious risk of bias¹	no serious inconsistency	no serious indirectness	serious²	none	46/99⁴ (46%)	82/119 (69%)	RR 0.67 (0.53 to 0.86)	112 fewer per 1000 (from 22 fewer to 183 fewer)	MODERATE	IMPORTANT

: CI: confidence interval; HR: hazard ratio; RR: relative risk

1: Risk of bias assessed using trial protocol

2: Quality of evidence downgraded by 1 because of imprecision of the effect estimate (< 300 events for dichotomous outcomes or < 400 patients for continuous outcomes)

3: Numbers of events or participants were not reported

4: CREST results presented at ASCO 2016 meeting: Hill J, Kay C, Morton D et al J Clin Oncol 34, 2016 (suppl; abstr 3507)

Table 10Quality assessment of expert evidence – redacted outcomes (as yet unpublished)

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Stenting + planned bowel resection or palliative care	Emergency bowel surgery	Relative (95% CI)	Absolute	Quality	Importance
30-day mortality - Curative intent
1	randomised trials	no serious risk of bias¹	no serious inconsistency	no serious indirectness	serious²	none	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	MODERATE	CRITICAL
3-year overall survival, event is death from any cause - Curative intent
1	randomised trials	no serious risk of bias¹	no serious inconsistency	no serious indirectness	serious²	none	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	MODERATE	IMPORTANT
Hospital stay (time to event analysis of leaving hospital)- Curative intent
1	randomised trials	no serious risk of bias¹	no serious inconsistency	no serious indirectness	serious²	none	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	MODERATE	IMPORTANT
Hospital stay - Palliative intent
1	randomised trials	no serious risk of bias¹	no serious inconsistency	no serious indirectness	serious²	none	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	[REDACTED TEXT]	MODERATE	IMPORTANT

: CI: confidence interval; HR: hazard ratio; RR: relative risk

1: Risk of bias assessed using trial protocol

2: Quality of evidence downgraded by 1 because of imprecision of the effect estimate (< 300 events for dichotomous outcomes or < 400 patients for continuous outcomes)

3: Numbers of events or participants were not reported