Clinical evaluation of flutamide and estramustine as initial treatment of metastatic carcinoma of prostate

Abstract

The efficacy and side effects of flutamide were compared with estramustine in patients with advanced prostatic carcinoma. Thirty patients with metastatic cancers but with no serious cardiovascular (CV) conditions were randomly assigned to receive treatment either with flutamide (250 mg X 3) or with estramustine (280 mg X 2). Clinical examination, bone scan, laboratory measurements, including coagulation studies were performed prior to randomization, every three months during year one, and at six-month intervals thereafter. The two groups were comparable with respect to age and tumor characteristics. However, more patients presented with skeletal pain among those later treated with flutamide. During an observation period of between one and two and one-half years, flutamide was discontinued in 1 case (7%) because of icterus, and estramustine in 3 cases (20%) because of CV complications. Of the remaining 14 flutamide-treated patients, 13 responded initially. Eleven of them relapsed, and 5 died of cancer. In the corresponding group of 12 estramustine-treated patients, there were 11 primary responders. Of these, only 2 relapsed and died as did the only nonresponder. The difference between the two groups with regard to relapse is significant (P less than 0.01), but not with regard to mortality. All estramustine-treated patients lost their libido, whereas only 20 per cent of the patients treated with flutamide did so. In the present limited material there was an initial favorable response to flutamide without signs of CV complications and with maintained libido in most cases. However, due to significantly increased risk for relapse compared with estramustine, flutamide cannot be recommended as single therapy except in cases where estrogens are contraindicated or when interference with libido and potency is unacceptable.