Adjuvant docetaxel after definitive radiotherapy for high-risk prostate cancer: A meta-analysis of randomized clinical trials.

Abstract

374 Background: In order to improve long term results for high-risk prostate cancer, several clinical trials have tested the addition of docetaxel chemotherapy. The outcomes of this trials have not led to clear conclusions. We conducted a meta-analysis of randomized phase 3 trials testing the efficacy of docetaxel after radiotherapy in high risk prostate cancer patients. Methods: A systematic review of PubMed (Medline), Embase and the Cochrane Library was conducted. We followed the PRISMA guidelines, three investigators independently selected the articles and verified inclusion criteria. We compared the overall survival and disease-free survival between the intervention group (adjuvant chemotherapy with docetaxel) and the control group (without adjuvant chemotherapy) by calculating the hazard ratio (HR) with 95% confidence intervals (CIs). Pooled effects were calculated using random-effects or fixed-effects models based on the heterogeneity of included studies. Results: 382 publications were identified, four phase III trials (STAMPEDE, RTOG0521, SPCG-13, GETUG 12) comparing docetaxel vs standard of care after radiotherapy for high-risk prostate cancer fulfilled the inclusion criteria with data from 2034 patients (1135 in placebo group and 899 in adjuvant docetaxel group). Heterogeneity was not found between the included studies for OS (I 2 0%), but it was found between studies for disease-free survival (I2 60%). Adjuvant docetaxel chemotherapy showed overall survival benefit when compared to ADT alone (HR 0,72 95% CI 0,54-0,96). Adjuvant docetaxel also improved the disease-free survival when compared to ADT alone (HR 0,74 95% CI 0,64-0,86). No evidence of publication bias was observed. Conclusions: This meta-analysis shows that docetaxel after definitive radiotherapy in high-risk prostate cancer is likely to be more effective than standard of care in terms of overall survival and disease-free survival. Further prospective studies are needed in order to increase the sample that would lead to show a more robust data.