Adjuvant chemotherapy for muscle invasive bladder cancer: A systematic review and meta-analysis

Abstract

4733 Background: Some studies have evaluated the role of adjuvant chemotherapy (CT) for muscle-invasive bladder cancer (BC), with conflicting results. In order to offer the totality of evidence available for clinical decision, we performed a systematic review and meta-analysis of randomized controlled trials (RCT) that compared surgery versus surgery plus adjuvant CT in the treatment of muscle-invasive BC. Methods: The main electronic databases (CENTRAL Cochrane, MEDLINE, LILACS) were scanned. We also searched trials register databases and hand searched meeting proceedings (ASCO, ESMO). The objective of this study was to investigate whether CT administered after surgery improves the survival and reduces recurrence rates of patients with muscle invasive BC. The data extracted from individual studies were pooled in a meta-analysis and the results are expressed as Peto’s Odds Ratio (OR) and the correspondent 95% confidence interval (95% CI). Heterogeneity was calculated according to the I index, based on the chi-square statistics. Subgroup analysis according to prognostic and methodological features was also performed. Results: Of 140 reports identified in the search, four trials with 272 participants (CT arm= 134; observation arm= 138) meet the inclusion criteria. A meta-analysis of four trials revealed that adjuvant CT was effective in reducing the recurrence rate (OR= 0.40; 95% CI 0.24 to 0.66) without evidence of heterogeneity (I2=57,9%). The difference in overall survival rate for adjuvant CT was not significant (OR=0.70; 95% CI 0.41 to 1.20) and no significant difference in treatment-related mortality was observed. Subgroup analysis according to node status was also performed: node positive patients had recurrence rate reduction (OR= 0,28; 95% CI 0.10 to 0.82); node negative patients had a similar recurrence rate reduction (OR=0.32; 95% CI 0.11 to 0.88). Conclusions: Adjuvant chemotherapy for muscle-invasive bladder cancer improves disease free survival, but has no effect on overall survival. Future RCTs should focus on long term follow up and determination of the ideal scheme of adjuvant chemotherapy in order to evaluate its real role in patients with bladder cancer. No significant financial relationships to disclose.