Treatment of metastatic endocrine-unresponsive carcinoma of the prostate gland with multiagent chemotherapy: indicators of response to therapy.

Eighty-eight patients with metastatic and hormonally unresponsive carcinoma of the prostate gland were treated with a multiagent chemotherapy protocol. Because of the difficulty in evaluating the response of patients to therapy, data were collected in a prospective fashion and analyzed for clinical or laboratory changes that correlated with improved survivorship. Decrease of initially abnormal values of either acid or alkaline phosphotase into the normal range was associated with prolonged survival; weight gain of more than 10% was also associated with improved survival. Thirty-three patients demonstrated a fall of acid or alkaline phosphatase into the normal range or they increased their weight by at least 10%. The median survival time for this group of patients was 76.1 weeks as compared to 28.2 weeks for patients who failed to exhibit these changes. In future studies of the treatment of metastatic prostate cancer, these changes might be used as criteria of response to therapy.