Androgen-deprivation therapy plus docetaxel-based chemotherapy in metastatic hormone-sensitive prostate cancer. A meta-analysis of randomized clinical trials.

188 Background: Androgen-deprivation therapy (ADT) is the standard of treatment for patients with newly diagnosed metastatic prostatic cancer. Nevertheless, recent trials have suggested a role for chemotherapy in these patients. We performed a systematic review and meta-analysis to assess the efficacy and safety of docetaxel-based chemotherapy in combination with ADT for patients with hormone-sensitive metastatic prostate cancer. Methods: Randomized clinical trials (RCT) were identified after systematic searching of electronic databases (MEDLINE, OVID and The Cochrane Central Register of Controlled Trials), as well as ASCO conference proceedings from 2010 to 2015. We included only RCT comparing ADT versus the combination of ADT plus docetaxel-based chemotherapy in patients with newly diagnosed metastatic prostate cancer. A random-effect model was used to determine the pooled hazard ratio (HR) for the efficacy outcomes: overall survival (OS) and clinical progression-free survival (PFS), according to the inverse-variance method. Heterogeneity was measured using the Q and I2statistics. Results: Three RCT (n = 2 262), were included in our meta-analysis (E3805, GETUG-AFU 15 and the M1 subgroup from STAMPEDE Trial). Docetaxel-based chemotherapy plus ADT was associated with improved OS (HR: 0.74; 95% CI: 0.60-0.90; p = 0.003). The heterogeneity of these trials was moderate (Tau2: 0.02; I2: 51%; p = 0.13). Clinical PFS was also significantly better in patients receiving docetaxel-based chemotherapy (HR: 0.67; 95% CI 0.55-0.82; p = 0.0001), with moderate between-study heterogeneity detected (Tau2: 0.01; I2: 42%; p = 0.19). Different subset of patients in these trials can explain the aforementioned heterogeneity. Regarding adverse drug reactions grade 3 or higher, neutropenia was reported in a range from 36% in the GETUG-AFU 15 Trial to 12% in the STAMPEDE trial and febrile neutropenia was reported from 6.1% in the E3805 Trial to 12% in the STAMPEDE Trial. Conclusions: The addition of docetaxel-based chemotherapy to ADT improves OS and clinical PFS. New trials are needed to determine which patients benefit the most from this intervention.