Authors' objectives

To evaluate the relative effect of percentage maximal cytoreduction surgery and other prognostic variables on survival among cohorts of patients with advanced-stage ovarian carcinoma, who were being treated with platinum-based chemotherapy.

Searching

MEDLINE was searched for articles published in English between 1 January 1989 and 31 December 1998. The headings and keywords were 'ovarian neoplasms', 'ovarian carcinoma', 'ovarian cancer' and 'surgery'. The bibliographies of the selected articles were reviewed for potentially relevant studies.

Study selection

Assessment of study quality

The authors did not state that they assessed validity.

Data extraction

The authors did not state how the data were extracted for the review, or how many reviewers performed the data extraction.

The following data were extracted and tabulated: study design; year the study was published; the number of patients; median patient age; the percentage of patients with stage IV disease; specified definition of maximal cytoreductive surgery and the percentage of patients achieving it; chemotherapy agents administered; dosage and prescribed administration schedule of the platinum compound used; and reported median survival time.

Methods of synthesis

Results of the review

Fifty-three studies including 81 patient cohorts (n=6,885) were included in the review. Fifty-five cohorts (n=5,442) came from randomised prospective trials, 24 (n=1,333) from non-randomised prospective trials, and 2 (n=110) from retrospective reviews.

There was a statistically significant positive correlation between percentage maximal cytoreduction and log median survival time; this correlation remained significant after controlling for all other variables (P<0.001). Each 10% increase in maximal cytoreduction was associated with a 5.5% increase in median survival time. When actuarial survival was estimated, cohorts with less than or equal to 25% maximal cytoreduction had a mean weighted median survival time of 22.7 months, whereas cohorts with more than 75% maximal cytoreduction had a mean weighted median survival time of 33.9 months an increase of 50%. The relationship between platinum dose-intensity and log median survival time was not statistically significant.

Authors' conclusions

During the platinum era, maximal cytoreduction was often the most powerful determinant of cohort survival among patients with stage III or IV ovarian carcinoma. Consistent referral of patients with apparent advanced ovarian cancer to expert centres for primary surgery may be the best means currently available for improving overall survival.

CRD commentary

The authors addressed a clear review question in terms of the interventions, participants, study designs and outcome measures that were to be included and assessed in the review. However, the literature search was poor with only MEDLINE being searched for studies published in the English language. It is therefore possible that both publication and language bias were introduced into the review process, and other relevant studies were missed. Two reviewers assessed the relevance of the primary studies for inclusion in the review, but the authors did not provide any details of whether the validity of the included studies was assessed. This makes it very difficult for the reader to assess the quality of the studies included in the review. The authors provided adequate details of the primary study characteristics for the reader to assess whether the authors' results and conclusions were consistent with the evidence base reviewed. The statistical analysis was appropriate, but the effect of study design on the results was not explored.

Overall, a number of biases could have been introduced into the review process, particularly in the literature search. The authors' results and conclusions were consistent with the evidence base reviewed, but should be treated with caution as other relevant studies may have been missed.

Implications of the review for practice and research

Practice: The authors stated that consistent referral of patients with advanced ovarian carcinoma to expert centres for initial surgery may be the best means currently available for improving the overall survival rate.

Research: The authors did not state any implications for further research.

Bibliographic details

Bristow R E, Tomacruz R S, Armstrong D K, Trimble E L, Montz F J. Survival effect of maximal cytoreductive surgery for advanced ovarian carcinoma during the platinum era: a meta-analysis. Journal of Clinical Oncology 2002; 20(5): 1248-1259. [PubMed: 11870167]

Original Paper URL

http://www.jco.org/

Indexing Status

Subject indexing assigned by NLM

MeSH

Aged; Female; Humans; Middle Aged; Neoplasm Staging; Ovarian Neoplasms /drug therapy /mortality /pathology /surgery; Platinum /administration & dosage /therapeutic use; Prognosis; Regression Analysis

AccessionNumber

12002000715

Database entry date

30/04/2004

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.