[Response to chemotherapy in endocrine therapy-relapsed and -resistant prostate cancer]

Effects of chemotherapy to endocrine therapy (castration with estrogen/antiandrogen)-relapsed (24 cases) or endocrine therapy-resistant (14 cases) prostate cancer were compared. Pretreatment clinical stages in these groups were stage D1 (3 cases) and D2 (35 cases). Regimens of chemotherapy in this study were as follows: cis-platinum (CDDP) (1 case), phosphamide (3 cases), combination of vincristine, phosphamide and peplomycin (5 cases), combination of cyclophosphamide, adriamycin (ADM) and CDDP (8 cases) and combination of phosphamide, ADM, and CDDP (21 cases). Response to chemotherapy and subsequent survival in these two groups were examined. When evaluated at 3 months after the start of the chemotherapy, partial response and stable cases were 50% and 36% in endocrine therapy-relapsed and -resistant groups, respectively. Because the worse performance status contained more cases in the endocrine therapy-resistant group, the response was compared at the same base of performance status, and the response was almost equal in the two groups. Survival in the endocrine therapy-relapsed group was better than that in the therapy-resistant group. When compared at the same base of performance status, the difference in survival time between the two groups was not evident. In conclusion, the response of chemotherapy was similar between endocrine therapy-relapsed and -resistant patients, and performance status was a main factor influencing the prognosis of endocrine therapy-refractory prostate cancer.