NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.
National Collaborating Centre for Cancer (UK). Colorectal Cancer: The Diagnosis and Management of Colorectal Cancer. Cardiff: National Collaborating Centre for Cancer (UK); 2011 Nov. (NICE Clinical Guidelines, No. 131.)
This publication is provided for historical reference only and the information may be out of date.
The objectives of this chapter were to determine:
- the most effective diagnostic intervention(s) for patients with suspected colorectal cancer to establish a diagnosis
- the most effective technique(s) to accurately stage disease in patients diagnosed with primary colorectal cancer.
2.1. Diagnostic investigations
Fewer than 10% of patients referred to NHS out-patient clinics on suspicion of symptomatic colorectal cancer are diagnosed with the condition. Patients are typically aged >55 years, with a high prevalence of co-morbidities which may increase the risk of complications and influence patients’ and clinicians’ choice of diagnostic intervention.
This section deals with patients whose condition is being managed in secondary care. It does not deal with triage systems for referrals directly from primary care that may include flexible sigmoidoscopy as the first test. Some of the patients discussed below may already have undergone investigations initiated by their general practitioner. Recommendations for urgent referral from primary care for patients with suspected colorectal cancer can be found in ‘Referral guidelines for suspected cancer’ NICE clinical guideline 277.
The aim of investigation is to achieve adequate examination of the entire colon and rectum. Effective diagnostic interventions in symptomatic patients suspected of having colorectal cancer need to have very high sensitivity (Box 2.1) for the detection of cancers and acceptable sensitivity for detection of adenomas with significant potential for malignant transformation. They must also have high specificity, be as safe as possible and be acceptable to patients, as all these investigations are unpleasant and invasive.
Historically, a number of different diagnostic interventions have been used to detect colorectal cancer, often guided by local expertise and preference. These interventions are colonoscopy, barium enema/flexible sigmoidoscopy and CT colonography. However the optimum diagnostic strategy for colorectal cancer has not yet been defined.
All initial diagnostic investigations require rigorous bowel cleansing preparation. Colonoscopy has for many years been regarded as the reference standard for diagnosing colonic pathology. Colonoscopy is known to have high sensitivity and specificity for detection of cancer, pre-malignant adenomas and other symptomatic colonic diseases. Colonoscopy also has the facility to take a biopsy from any suspected lesion (thereby increasing diagnostic accuracy and also permits complete removal of most benign lesions during the same procedure. However, it may not be possible to perform complete colonoscopy in a proportion of patients due to inadequate bowel preparation, poor tolerance of the procedure, inter-operator variation in terms of completion rate or the presence of an obstructing lesion in the distal colon. Patients with serious cardiorespiratory or neurological co-morbidity may be at high risk from potential complications of colonoscopy (for example colonic perforation, effects of sedation). Such patients might be better served by alternative investigations.
Barium enema is a long-established radiological investigation of the colon and rectum offering completion rates higher than those historically recorded for colonoscopy, without the need for patient sedation and with a lower incidence of serious complications. However, there is limited published evidence of the diagnostic accuracy of barium enema and there is concern that it is less sensitive than colonoscopy. This has led many centres to offer patients a combined investigative pathway of flexible sigmoidoscopy (endoscopic examination of the distal large bowel) followed by barium enema. There is a perception that this combination has comparable sensitivity to colonoscopy for detection of cancer. This investigative route also allows biopsy of lesions detected during flexible sigmoidoscopy.
Computerised tomography colonography (CT colonography) is a more recent radiological investigation in which cross-sectional images of the abdomen and pelvis are obtained following laxative preparation and insufflation of the large bowel with air or carbon dioxide. The images are then analysed using 2-D and 3-D image reconstruction techniques. Colonoscopy can be performed at a later date to obtain biopsy confirmation of suspected tumours. It is thought that CT colonography may approach the sensitivity of colonoscopy for detection of larger polyps (>1cm). By inference, CT colonography may therefore have high sensitivity for cancer detection, but no study of sufficient statistical power has been published that supports this inference. Some studies of CT colonography suggest large variations in performance between individual operators and different centres. Reported complication and completion rates for CT colonography compare favourably with those for colonoscopy. The technique is substantially less invasive than colonoscopy and does not require patient sedation. In addition to allowing interrogation of the large bowel, CT colonography produces images of all the abdominal and pelvic organs, and this can result in clinically important chance findings of abnormalities at other sites.
When a patient is referred for investigation of symptoms suspicious of colorectal cancer, to maximise the benefit of the diagnostic intervention it is essential that the initial clinical consultation includes:
- accurate recording of the nature and duration of symptoms
- with the patient’s consent, thorough digital examination of the rectum and palpation of the abdomen
- accurate recording of significant comorbidities which may increase the risks arising from investigative procedures
- explanation of the investigations which may be offered, including the morbidity, risks and benefits
- discussion of the patient’s preferences.
Clinical question: What is the most effective diagnostic intervention(s) for patients with suspected colorectal cancer to establish a diagnosis?
Clinical evidence
The volume of evidence was variable across the interventions of interest with a large volume of evidence available investigating CT colonography but little to no evidence for other interventions of interest.
There were some concerns relating to the applicability of the evidence to the population of interest as there was a degree of inconsistency in the types of patients included in studies. There was some degree of consistency in the results reported in systematic reviews, though as there was a high degree of overlap in the included studies, this was not surprising.
The quality of evidence available varied according to the intervention with high quality evidence available for CT colonography and very low quality evidence available for flexible sigmoidoscopy plus barium enema. No evidence was available for flexible sigmoidoscopy plus colonoscopy.
From two systematic reviews and meta-analysis (Chaparro et al., 2009; Halligan et al., 2005), per polyp sensitivity of CT colonography was similar and both reviews reported higher sensitivities for larger polyps.
CT colonography versus conventional colonoscopy
Chaparro et al. (2009) reported sensitivities which ranged from 28–100% for all polyps >6mm with an overall pooled sensitivity of 66% [95% CI: 64–68%]. From one systematic review (Chaparro et al., 2009), the per patient sensitivity for CT colonography ranged from 24–100% across the individual studies and the overall pooled sensitivity was 69% [95% CI: 66–72%].
Mulhall et al., 2005 reported that per patient sensitivity ranged from 21% to 96% with an overall pooled sensitivity of 70% [95% CI: 53–87%]. The overall specificity of CT colonography was reported to be 83% [95% CI: 81–84%, I2=89%[ (Chaparro et al., 2009).
Sensitivity and specificity of CT colonography were reported to increase with larger polyp size in all three systematic reviews (Chaparro et al., 2009; Halligan et al., 2005; Mulhall et al., 2005).
Flexible sigmoidoscopy plus air contrast barium enema versus conventional colonoscopy
Two randomised trials (Rex et al., 1990; Rex et al., 1995) provide poor quality evidence comparing flexible sigmoidoscopy plus air contrast barium enema with conventional colonoscopy.
Rex et al. (1990) reported that air contrast barium enema was sufficient to rule out major pathology in 157 patients and reasons for unsuccessful flexible sigmoidoscopy plus air contrast barium enema included; inability to distend or fill the right colon adequately in 5 patients, repeatedly inadequate preparation to rule out mass lesions (n=4) and inability to retain the enema adequately in 2 patients. Flexible sigmoidoscopy plus air contrast barium enema findings were normal in 48/168 patients and abnormalities identified included haemorrhoids (n=1), diverticulosis (n=82), any polyp (n=43), stricture (n=3) and cancer (n=4).
Colonoscopy was successful in 151 patients (insertion to the cecum) and reasons for unsuccessful colonoscopy included; obstructing cancers in 6 patients and technical factors in 7 patients. Colonoscopy findings were normal in 18/162 patients (Rex et al., 1990).
From one randomised trial (Rex et al., 1990) there was a significant difference between the arms in relation to the proportion of patient’s recommended alternative lower GI procedures (p 0.0001). 53/168 (32%) patients in the flexible sigmoidoscopy group were referred for subsequent colonoscopy due to inadequate study (n=11), for polypectomy (n=38) and for biopsies on lesions outside the reach of flexible sigmoidoscopy. 13/164 (8%) patients in the colonoscopy arm were referred for flexible sigmoidoscopy plus air contrast barium enema because of difficulty advancing the colonoscope to the cecum (Rex et al., 1990).
In the second trial (Rex et al., 1995) patients undergoing flexible sigmoidoscopy were more likely to require an alternative intervention such as colonoscopy than were patients undergoing colonoscopy to require air contrast barium enema (OR=2.07 [95% CI: 1.47–16.4]).
Recommendations
- Advise the patient that more than one investigation may be necessary to confirm or exclude a diagnosis of colorectal cancer.
- Offer colonoscopy to patients without major comorbidity, to confirm a diagnosis of colorectal cancer. If a lesion suspicious of cancer is detected, perform a biopsy to obtain histological proof of diagnosis, unless it is contraindicated (for example, patients with a blood clotting disorder).
- Offer flexible sigmoidoscopy then barium enema for patients with major comorbidity. If a lesion suspicious of cancer is detected, perform a biopsy unless it is contraindicated.
- Consider computed tomographic (CT) colonography as an alternative to colonoscopy or flexible sigmoidoscopy then barium enema, if the local radiology service can demonstrate competency in this technique. If a lesion suspicious of cancer is detected on CT colonography, offer a colonoscopy with biopsy to confirm the diagnosis, unless it is contraindicated.
- Offer patients who have had an incomplete colonoscopy:
- repeat colonoscopy or
- CT colonography, if the local radiology service can demonstrate competency in this technique or
Linking evidence to recommendations
The GDG considered true positive or true negative diagnoses of colorectal cancer to be the most important outcomes for this question. True negative results were also considered important because the large majority of patients referred will not have colorectal cancer. Avoidance of false negative results was also important, but in a population with low incidence of colorectal cancer, the absolute risk of a false-negative diagnosis of colorectal cancer will be small.
The GDG noted that investigation (particularly with CT colonography) may result in diagnoses of conditions other than colorectal cancer. The GDG was unable to find sufficient evidence of benefit or harm to attach a relative significance to this outcome.
There were few studies of high quality that directly compared two or more of the investigations of interest. Many of the studies of CT colonography were performed on asymptomatic patients or used detection of polyps, rather than colorectal cancer, as the primary end-point.
The GDG concluded that colonoscopy has the highest clinical efficacy for diagnosis of colorectal tumours, but is generally considered more invasive and has higher morbidity than CT colonography or barium enema. Completion rates may vary considerably due to patient factors and operator expertise. Colonoscopy permits immediate biopsy confirmation of colorectal cancer; adenomas may also be removed during the same procedure. Therefore the GDG recommended colonoscopy as the first investigation for the diagnosis of colorectal tumours. The GDG recognised that diagnostic colonoscopy might fail because of a variety of reasons for example poor bowel preparation and felt that in certain circumstances a repeat procedure might be appropriate.
The GDG noted that several studies suggest that CT colonography is as sensitive as colonoscopy for detection of polyps >9mm in diameter. However they noted that there was no evidence of equivalent sensitivity between CT colonography and colonoscopy for the detection of colorectal cancer. The GDG was also concerned by variability in diagnostic performance between operators and institutions. The GDG were aware that CT colonography appears at face value to carry a higher risk of colonic perforation than colonoscopy, however the GDG considered that this observation may be explained by its superior ability to detect small, clinically inconsequential perforations which cannot be seen on colonoscopy. The GDG therefore recommended CT colonography as an alternative to colonoscopy.
The GDG recognised that published studies indicate that flexible sigmoidoscopy combined with barium enema is almost as sensitive as colonoscopy for detection of colorectal cancer. However the GDG noted that this combination has much poorer specificity. Morbidity is lower than for colonoscopy but involves multiple investigations in sequence. Both barium enema and CT colonography entail exposure to ionising radiation. This is potentially harmful, particularly to young patients. However, as the majority of patients undergoing investigation are aged over 55 and ongoing technical developments are enabling substantial reduction in dose, the GDG saw this as a relatively minor concern.
The GDG agreed that colonoscopy and the package of flexible sigmoidoscopy then barium enema were widely available, and that CT colonography was becoming increasingly available as more practitioners gain expertise in its use. They therefore decided that availability was not a significant factor in what modality should be recommended.
No existing published economic studies that included all the interventions and comparators of interest were identified. The GDG considered undertaking a cost-effectiveness modelling exercise for this topic but agreed that it would be difficult to construct a model structure that appropriately took into account all downstream events beyond test accuracy. In addition it was noted that results of a prospective trial conducted in the UK (SIGGAR1) were anticipated. This study was designed to compare colonography vs barium enema and CT colonography versus colonoscopy. The protocol for the SIGGAR1 study includes collection of data on subsequent tests and healthcare resource use as well as a planned cost-utility analysis. Given the overlap in timing and objectives of the planned economic analysis that is part of the SIGGAR1 study with any potential modelling efforts for this topic within the guideline, it was agreed that resources for economic modelling should be directed towards other higher priority topics.
2.2. Staging of colorectal cancer
Initial staging of newly diagnosed colorectal cancer involves an assessment of local spread and detection of the presence or absence of distant metastases. Historically, staging relied on contrast-enhanced CT, with the addition of digital rectal examination (DRE) for low rectal tumours. The introduction of new imaging modalities (particularly endorectal ultrasound (EUS), MRI and PET-CT) and variation in their uptake, quality and availability has meant there is no standard approach to staging colorectal cancer.
For the purpose of this guideline the GDG has adopted TNM5 to be in line with the Royal College of Pathologists (see Appendix 1).
In patients diagnosed with rectal cancer, local recurrence is a particular problem. Accurate pre-treatment staging for rectal cancer can both identify characteristics that predict for local recurrence and determine the appropriate treatment strategy to minimise local recurrence. The most important characteristic in determining the likelihood of local recurrence is the circumferential resection margin, which can be predicted by imaging. EUS and MRI have been used pre-treatment to assess encroachment on the circumferential resection margin (CRM) but there is uncertainty over which imaging modality is most effective and it is possible that the optimal modality may vary with the clinical situation.
Therefore the issues to be addressed are:
- which modality(s) demonstrates distant metastases most accurately
- which modality is best for assessing T stage in rectal cancer
- which modality best defines the mesorectal fascia and predicts its anatomical relationship to the invading tumour in rectal cancer i.e. the CRM.
Clinical question: For patients diagnosed with primary colorectal cancer, what is the most effective technique(s) in order to accurately stage the disease (excluding pathology)?
Clinical evidence
There were three systematic reviews of case series studies (Kwok et al., 2000; Bipat et al., 2004; Dighe et al., 2010) and a large volume of low quality case series studies with which to address this topic (Akin et al., 2004; Beets-Tan et al., 2001; Beynon et al., 1986; Bianchi et al., 2005; Brown et al., 2004; Brown et al., 2003; Brown et al., 1999; Chun et al., 2006; Dirisamer et al., 2010; Fillipone et al., 2004; Fuchsjager et al., 2003; Halefoglu et al., 2008; Kantorova et al., 2003; Kim et al., 2007; Kim et al., 2006; Kulinna et al., 2004a; Kulinna et al., 2004b; Llamas-Elvira et al., 2007; Low et al., 2003; Mainenti et al., 2006; Mercury Study Group, 2007; Mercury Study Group, 2006; Nicholls et al., 1982; Rafaelsen et al., 1994; Rao et al., 2007; Salerno et al., 2009; Tatli et al., 2006; Tateishi et al., 2007).
The evidence body relating specifically to colon cancer was poor, with only a single systematic review available (Dighe et al., 2010). The remainder of included studies related either to rectal cancer only or to colorectal cancer where it was not possible to separate the colon patients from the rectal patients. There appears to be a large degree of variation across the body of evidence in relation to interventions, outcomes reported, inclusion and exclusion criteria, the standard to which the interventions were compared and names/terminology used across studies.
Colon cancer
Dighe et al. (2010) investigated the accuracy and limitations of CT in identifying poor prognostic features in colon cancer and reported (from 8 studies) that sensitivity was 92% [95% CI: 87–95%] and specificity was 81% [95% CI: 70–89%] for distinguishing between T3 and T4 tumours and for the distinction between T1/T2 and T3/T4 tumours sensitivity was 86% [95% CI: 78–92%[ and for lymph node involvement, sensitivity was 70% [95% CI: 59–80%] and specificity was 78% [95% CI: 66–86%].
Rectal cancer
For digital rectal exam, a total of 4 studies reported results (Beynon et al., 1986; Mercury Study Group, 2006; Brown et al., 2004; Rafaelson et al., 1994). Reported sensitivities and specificities ranged from 38–68% and 74–83% respectively.
From two systematic reviews (Kwok et al., 2000; Bipat et al., 2004) it appears that endorectal sonography/endorectal ultrasound had the highest sensitivity, specificity and accuracy of the modalities investigated (CT, endorectal sonography/endorectal ultrasound and MRI). Kwok et al. (2000) reported a pooled sensitivity, specificity and accuracy for endorectal sonography of 93%, 78% and 87% respectively for wall penetration and 71%, 76% and 74% respectively for nodal involvement. Bipat et al. (2004) reported summary estimates of sensitivity and specificity for endorectal ultrasound of 94% and 86% respectively for muscularispropria invasion, 90% and 75% respectively for peri-rectal tissue invasion and 67% and 78% respectively for lymph node involvement compared with sensitivity and specificity for MRI of 90% and 69% respectively for muscularispropria invasion, 82% and 76% respectively for peri-rectal tissue invasion and 66% and 76% respectively for lymph node involvement. For muscularispropria invasion, endorectal sonography specificity was significantly higher than that of MRI (p=0.02); for peri-rectal tissue invasion, endorectal ultrasound sensitivity was significantly higher than that of CT (p<0.001) and MRI (p=0.003).
Specific UK evidence was provided from the Mercury Study group (2006 (2007) investigating MRI in the staging of rectal cancer. The accuracy of MRI for predicting the status of circumferential resection margin (presence/absence of tumour) by initial imaging or imaging after preoperative treatment was 88% [95% CI: 85–91%], sensitivity was 59% [95% CI: 46–72%] and specificity was 92% [95% CI: 90–95%[. For patients undergoing primary surgery with no preoperative treatment (n=311), accuracy of prediction of a clear margin was 91% [95% CI: 88–94%], sensitivity of 42% and specificity of 98%. For patients undergoing preoperative chemoradiotherapy or long-course radiotherapy the accuracy of prediction of clear margins on MRI was 77% [95% CI: 69–86%], sensitivity was 94% and specificity was 73%.
Two studies investigated the use of FDG-PET (Kantorova et al., 2003; Llamas-Elvira et al., 2007). For lymph node involvement the reported sensitivity ranged from 21–29%, specificity ranged from 88–95% and accuracy ranged from 56–75% and for liver involvement sensitivity was 78%, specificity was 96% and accuracy was 91%.
Interobserver agreement was not addressed in all studies, though the studies which did evaluate interobserver agreement (Fillipone et al., 2004; Tatli et al., 2006; Kim et al., 2006) reported good to excellent agreement for interventions being investigated.
Recommendations
- Offer contrast enhanced CT of the chest, abdomen and pelvis, to estimate the stage of disease, to all patients diagnosed with colorectal cancer unless it is contraindicated. No further routine imaging is needed for patients with colon cancer.
- Offer magnetic resonance imaging (MRI) to assess the risk of local recurrence, determined by anticipated resection margin, tumour and lymph node staging, to all patients with rectal cancer unless it is contraindicated.
- Offer endorectal ultrasound to patients with rectal cancer if MRI shows disease amenable to local excision or if MRI is contraindicated.
- Do not use the findings of a digital rectal examination as part of the staging assessment.
Linking evidence to recommendations
The GDG placed a high value on accurate staging at presentation because this information informs the optimum treatment strategy for patients with colorectal cancer. The evidence consisted of two good quality systematic reviews and several low-quality case series studies. The GDG noted that no study specifically addressed patients with colon cancer.
The GDG considered the imaging interventions themselves to have minimal side effects. However, they were aware that there were potential harms for patients who were incorrectly staged and therefore received sub-optimal treatment, possibly resulting in a higher risk of subsequent local recurrence or future morbidity associated with inappropriate treatment.
The GDG noted that there was no evidence that any of the imaging modalities investigated was superior at local staging for patients with colon cancer. The GDG decided not to make a specific recommendation regarding further imaging, as they agreed that all the relevant staging information would be provided by the initial CT scan
In patients with rectal cancer, the GDG were aware that the available evidence had shown EUS to have higher sensitivity, specificity and accuracy compared to MRI or CT for identifying those patients whose tumours are suitable for local resection. The GDG noted that EUS is not appropriate in bulky, obstructing tumours and does not visualise the total extent of nodal disease in the pelvis. It was also noted that the evidence may reflect non-UK practice because EUS is not widely used in the UK. There was also significant inter-observer variation in the performance of EUS. The GDG therefore recommended MRI be used for the initial assessment of patients with rectal cancer and that EUS be considered if the MRI suggested disease which was amenable to local resection.
The GDG recognised that although DRE has a role in diagnosis and assessment of rectal cancer, evidence showed it is less sensitive and specific than the other modalities for staging rectal cancer. Therefore they recommended it was not used for staging.
This clinical question was considered a low priority for economic analysis because of the complexity that would be involved in downstream decisions which could vary according to the diagnostic interventions of interest (i.e. different interventions may provide different kinds of information to inform treatment decisions) and also because of the poor quality of available data to inform an economic analysis.
References
- Akin O, Nessar G, Agildere AM, Aydog G. Preoperative staging of rectal cancer with endorectal MR imaging: Comparison with histopathologic findings. Journal of Clinical Imaging. 2004;28:432–438. [PubMed: 15531145]
- Beets-Tan RGH, Beets GL, Vliegen RFA, Kessels AGH, Van Boven H, De Bruine A, von Meyenfeldt MF, Baeten CGMI, van Engelshoven JMA. Accuracy of magnetic resonance imaging in prediction of tumour-free resection margin in rectal cancer surgery. The Lancet. 2001;357:497–504. [PubMed: 11229667]
- Beynon J, Mortensen NJ, Foy DMA, Channer JL, Virjee J, Goddard P. Preoperative assessment of local invasion in rectal cancer: digital examination, endoluminalsonography or omputed tomography. British Journal of Surgery. 1986;73:1015–1017. [PubMed: 3539255]
- Bianchi P, Ceriami C, Rottoli M, Torzilli G, Pompili G, Malesci A, Ferraroni M, Montorsi M. Endoscopic ultrasonography and magnetic resonance in preoperative staging of rectal cancer: comparison with histological findings. Journal of Gastrointestinal Surgery. 2005;9(9):1222–1227. [PubMed: 16332477]
- Bipat S, Glas AS, Slors FJM, Zwinderman AH, Bossuyt PMM, Stoker J. Rectal cancer: local staging and assessment of lymph node involvement with endoluminal US, CT and MR imaging – A meta-analysis. Radiology. 2004;232:773–783. [PubMed: 15273331]
- Brown G, Davies S, Williams GT, Bourne MW, Newcombe RG, Radcliffe AG, Blethyn J, Dallimore NS, Rees BI, Phillips CJ, Maughan TS. Effectiveness of preoperative staging in rectal cancer: digital rectal examination, endoluminal ultrasound or magnetic resonance imaging? British Journal of Cancer. 2004;91:23–29. [PMC free article: PMC2364763] [PubMed: 15188013]
- Brown G, Richards C, Bourne A, Newcombe R, Radcliffe A, Dallimore N, Williams G. Morphological predictors of lymph node status in rectal cancer with the use of high-spatial resolution MR imaging with histopathological comparison. Radiology. 2003;227:371–377. [PubMed: 12732695]
- Brown G, Richard C, Newcombe RG, Dallimore NS, Radcliffe AG, Carey DP, Bourne MW, Williams GT. Rectal carcinoma: thin section MR imaging for staging in 28 patients. Radiology. 1999;211:215–222. [PubMed: 10189474]
- Chaparro M, Gisbert J, del Campo L, Cantero J, Mate J. Accuracy of computed tomographic colonography for the detection of polyps and colorectal tumours: a systematic review and meta-analysis. Digestion. 2009;80:1–17. [PubMed: 19407448]
- Chun HK, Choi D, Kim MJ, Lee J, Yun SH, Kim SH, Lee SJ, Kim CK. Preoperative staging of rectal cancer: comparison of 3-T high field MRI and endorectal sonography. American Journal of Roentgenology. 2006;187(6):1557–1562. [PubMed: 17114550]
- Dighe S, Purkayastha S, Swift I, Tekkis PP, Darzi A, A’Hern R, Brown G. Diagnostic precision of CT in local staging of colon cancers: a meta-analysis. Clinical Radiology. 2010;65:708–719. [PubMed: 20696298]
- Dirisamer A, Halpern B, Flory D, Wolf F, Beheshti M, Mayerhoefer ME, Langsleger W. Performance of integrated FDG-PET/contrast enhanced CT in the staging and restaging of colorectal cancer: comparison with PET and enhanced CT. European Journal of Radiology. 2010;73:324–328. [PubMed: 19200683]
- Fillipone A, Ambrosini R, Fushi M, Marinelli T, Genovesi D, Bonomo L. Preoperative T and N staging of colorectal cancer: accuracy of contrast-enhanced multi-detector row CT colonography – initial experience. Radiology. 2004;231:83–90. [PubMed: 14990815]
- Fuchsjager M, Maier A, Schima W, Zebedin E, Herbst F, Mittlbock M, Wrba F, Lechner G. Comparison of transrectal sonography and double-contrast MR imaging when staging rectal cancer. American Journal of Roentgenology. 2003;181(2):421–427. [PubMed: 12876020]
- Halefoglu A, Yildirim S, Avlanmis O, Sakiz D, Baykan A. Endorectal ultrasonography versus phased array magnetic resonance imaging for preoperative staging of rectal cancer. World Journal of Gastroenterology. 2008;14(22):3504–3510. [PMC free article: PMC2716612] [PubMed: 18567078]
- Halligan S, Altman D, Taylor S, Mallett S, Deeks J, Bartram C, Atkin W. CT colonography in the detection of colorectal polyps and cancer: systematic review, meta-analysis and proposed minimum data set for study level reporting. Radiology. 2005;237(3):893–904. [PubMed: 16304111]
- Kantorova I, Lipska L, Belohlavek O, Visokai V, Trubac M, Schneiderova M. Routine 18F-FDG PET preoperative staging of colorectal cancer: comparison with conventional staging and its impact on treatment decision making. Journal of Nuclear Medicine. 2003;44(11):1784–1788. [PubMed: 14602860]
- Kim CK, Kim SH, Choi D, Kim MJ, Chun HK, Lee SJ, Lee JM. Comparison between 3-T magnetic resonance imaging and multi-detector row computed tomography for the preoperative evaluation of rectal cancer. Journal of Computer Assisted Tomography. 2007;31:853–859. [PubMed: 18043346]
- Kim CK, Kim SH, Chun HK, Lee WY, Yun SH, Song SY, Choi D, Lim HK, Kim MJ, Lee J, Lee SJ. Preoperative staging of rectal cancer: accuracy of 3-Tesla magnetic resonance imaging. European Radiology. 2006;16(5):972–980. [PubMed: 16416276]
- Kulinna C, Eibel R, Matzek W, Bonel H, Aust D, Strauss T, Reiser M, Scheidler J. Staging of rectal cancer: diagnostic potential of multi-planar reformatting with multidetector CT. American Journal of Roentgenology. 2004;183:421–427. [PubMed: 15269036]
- Kulinna C, Scheidler J, Strauss T, Bonel H, Herrmann K, Aust D, Reiser M. Local staging of rectal cancer: assessment with double contrast multislice computed tomography and transrectal ultrasound. Journal of Computer Assisted Tomography. 2004;28(1):123–30. [PubMed: 14716245]
- Kwok H, Bisset IP, Hill GL. Preoperative staging of rectal cancer. International Journal of Colorectal Disease. 2000;15(1):9–20. [PubMed: 10766086]
- Llamas-Elvira JM, Rodriguez-Fernandez A, Gutierrez Sainz J, Gomez-Rio M, Bellon-Guardia M, Ramos Font C, Rebollo Aguirre AC, Cabello Garcia D, Ferron Orihuela A. Fluorine-18 fluorodeoxyglucose PET in the preoperative staging of colorectal cancer. European Journal of Nuclear Medicine and Molecular Imaging. 2007;34(6):859–867. [PubMed: 17195075]
- Low RN, McCue M, Barone R, Saleh F, Song MR staging of primary colorectal carcinoma: comparison with surgical and histopathological findings. Abdominal Imaging. 2003;28(6):784–793. [PubMed: 14753591]
- Mainenti PP, Cirillo LC, Camera L, Perscio F, Cantalupo T, Pace L, De Palma GD, Persico G, Alvatore M. Accuracy of single phase contrast enhanced multidetector CT colonography in the preoperative staging of colorectal cancer. European Journal of Radiology. 2006;60:453–459. [PubMed: 16965883]
- Mercury Study Group. Extramural depth of tumour invasion at thin section MR in patients with rectal cancer: results of the Mercury Study. Radiology. 2007;243(1):132–139. [PubMed: 17329685]
- Mercury Study Group. Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study. British Medical Journal. 2006;333(7572):779. [PMC free article: PMC1602032] [PubMed: 16984925]
- Mulhall B, Veerappan G, Jackson J. Meta-analysis: computed tomographic colonography. Annals of Internal Medicine. 2005;142:635–650. [PubMed: 15838071]
- Nicholls RJ, Mason AY, Morson BC, Dixon AK, Fry IK. The clinical staging of rectal cancer. British Journal of Surgery. 1982;69:404–409. [PubMed: 7104612]
- Rafaelsen S, Kronborg O, Fenger C. Digital rectal examination and transrectal ultrasonography in staging of rectal cancer. Acta Radiology. 1994;35(3):300–304. [PubMed: 8192972]
- Rao SX, Zeng MS, Xu JM, QXU, Chen CZ, Li RC, Hou YY. Assessment of T-staging and mesorectal fascia status using high-resolution MRI in rectal cancer with rectal distention. World Journal of Gastroenterology. 2007;13(30):4141–4146. [PMC free article: PMC4205321] [PubMed: 17696238]
- Rex DK, Mark D, Clarke B, Lappas JC, Lehman GA. Flexible sigmoidoscopy plus air contrast barium enema versus colonoscopy for evaluation of symptomatic patients without evidence of bleeding. Gastrointestinal Endoscopy. 1995;42(2):132–138. [PubMed: 7590048]
- Rex DK, Weddle RA, Lehman GA, Pound DC, O’Connor KW, Hawes RH, Dittus RS, Lappas JC, Lumeng L. Flexible sigmoidoscopy plus air contrast barium enema versus colonoscopy for suspected lower gastrointestinal bleeding. Gastroenterology. 1990;98:855–861. [PubMed: 2107112]
- Salerno GV, Daniels IR, Moran BJ, Heald RJ, Thomas K, Brown G. Magnetic resonance imaging prediction of an involved surgical resection margin in low rectal cancer. Diseases of the Colon and Rectum. 2009;52(4):632–639. [PubMed: 19404067]
- Tatli S, Mortele K, Breen E, Bleday R, Silverman S. Local staging of rectal cncer using combined pelvic phased array and endorectal coil MRI. Journal of Magnetic Resonance Imaging. 2006;23(4):534–540. [PubMed: 16523466]
- Tateishi U, Maeda T, Morimoto T, Miyake M, Arai Y, Kim E. Non-enhanced CT versus contrast enhanced CT in integrated PET/CT studies for nodal staging of rectal cancer. European Journal of Nuclear Medicine and Molecular Imaging. 2007;34(10):1627–1634. [PubMed: 17530248]
Footnotes
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- Investigation, diagnosis and staging - Colorectal CancerInvestigation, diagnosis and staging - Colorectal Cancer
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