Chemotherapy in patients with prostate specific antigen-only disease after primary therapy for prostate carcinoma: A phase II trial of oral estramustine and oral etoposide

BACKGROUND. A Phase II study was initiated to evaluate the effectiveness of an oral regimen of etoposide and estramustine in patients with early recurrent prostate carcinoma. METHODS. Patients with early recurrent prostate carcinoma as indicated by an increasing prostate specific antigen (PSA) level and without any evidence of metastatic disease were treated with oral etoposide 50 mg/m²/day and estramustine 15 ms/kg/day in divided doses for 21 days, followed by a 7-day rest period. Patients received a maximum of four cycles. RESULTS. Eighteen patients were entered in this study. The median serum PSA was 3.1 (range, 0.3-30.3) at the time of entry into the trial. Sixteen patients were assessable for response. Serum PSA declined to undetectable levels in 13 patients with 2 additional patients meeting the criteria for partial response; the median duration of response was 8.5 months (range, 1-18 months). Most patients developed gastrointestinal, cardiac, or hematologic complications. Grade 3 toxicities included neutropenia (one patient), deep venous thrombosis (three patients), and chest pain (one patient). One patient developed acute myelogenous leukemia (French-American-British, acute myelogenous leukemia MS) 23 months after initiating the chemotherapy. CONCLUSIONS. The combination of oral etoposide and oral estramustine resulted in a high rate but only a short duration of response in patients with early recurrent prostate carcinoma. The regimen was poorly tolerated, and the toxicity was significant. This regimen should not be considered standard therapy for the treatment of early recurrent prostate carcinoma, but further exploration of treatment in this setting is warranted.