Chemotherapy plus estramustine for management of castration-resistant prostate cancer: meta-analysis of randomized...

Estramustine, an agent with both hormonal and non-hormonal effects in men, is supposed to be effective in treating castration-resistant prostate cancer. However, previous studies have reported conflicting results. We conducted this meta-analysis to evaluate the efficacy and toxicity of additional estramustine to chemotherapy.

Data sources including PubMed, Medline, EMBASE, and Cochrane Controlled Trials Register were searched to identify potentially relevant randomized controlled trials. Prostate specific antigen (PSA) response, overall survival, and grade 3 to 4 toxicity were analyzed.

Seven randomized controlled trials, a total of 839 patients, were enrolled. The pooled odds ratio for PSA response was 3.02 (95% CI=1.69-5.39, P=.0002); the pooled hazard ratio for overall survival was .95 (95% CI=.80-1.14, P=.58); the pooled odds ratio for nausea/vomiting and cardiovascular toxicity were 3.90 (95% CI=1.05-14.45, P=.04) and 2.22 (95% CI=1.15-4.30, P=.02). No significant difference was detected for neutropenia, anemia, thrombocytopenia, diarrhea, fatigue, or neuropathy (P>.05).

According to this meta-analysis, chemotherapy with additional estramustine increased the PSA response rate. However, it increased the risk of grade 3 or 4 adverse effects such as nausea/vomiting and cardiovascular events, and the overall survival was not improved for castration-resistant prostate cancer patients.