Background: A low-dose chemotherapy consisting of docetaxel, estramustine and dexamethasone was investigated for its beneficial effect and feasibility in Japanese patients with metastatic castration-resistant prostate cancer (CRPC).
Methods: Seventy-two Japanese patients with metastatic CRPC were enrolled to receive docetaxel (25 mg/m(2) on days 2 and 9), estramustine phosphate (280 mg orally twice daily from day 1 to day 3 and from day 8 to day 10) and dexamethasone (0.5 mg orally twice daily) every 21 days.
Results: The median age of the patients was 72 years and 64 patients (89 %) had ≥grade 1 anemia at entry. The median total number of courses administered was 8.5 (range 1-93). Forty-two patients (58 %) had a prostate-specific antigen (PSA) decline of ≥50 %. The median progression-free survival and overall survival were 6 and 23 months, respectively. Fifteen patients (21 %) improved and 53 patients (74 %) were stable in their performance status. Of the 40 patients with bone pain, 25 patients (63 %) showed pain reduction. Among 71 patients assessable for their hemoglobin levels, 21 patients (30 %) achieved an increase of at least 1.0 g/dl. Of the 5 patients who terminated treatment because of ≥grade 3 toxicity, 4 patients had pneumonitis and one patient had anemia. Only one patient developed ≥grade 3 neutropenia.
Conclusions: The low-dose combination of docetaxel, estramustine and dexamethasone is active and tolerable with beneficial effects on serum PSA levels, performance status, anemia and bone pain in Japanese patients with CRPC. This regimen is a reasonable option for elderly patients with bone disease at risk of hematologic toxicity.