[Clinical studies on endocrine therapy for prostatic carcinoma (5): Analyses of relapse from endocrine therapy]

Prostate carcinomas are well known to be initially responsive to endocrine therapy. However, a significant number of the patients experience a relapse from endocrine therapy during the follow-up period. We clinically analyzed various aspects of the relapse which indicate a limitation in the effectiveness of endocrine therapy for prostate carcinoma. In a total of 372 patients, 117 (31.5%) had some evidence of local relapse such as regrowth of the primary lesion, or a generalized relapse such as re-elevation of total acid phosphatase, reactivation of previously present metastasis or the new appearance of metastasis, during endocrine therapy. Of these, one-fourth had local relapse alone and the remainder showed generalized relapse. The interval from the start of the treatment to the time of relapse tended to become shorter; 45.9 months (mean) in stage B, 36.8 in stage C and 29.3 in stage D, according to the stage progression. As to the non-relapse rate of the primary lesion, no differences were found among the stage, with the rate being approximately 90% at the fifth year in each stage. However, the generalized relapse-rate tended to increase with the stage progression. In the generalized relapse, the patients of stage C or D showed a non-relapse rate of 71.7% or 67.4%, respectively. Most of the generalized relapse appeared within five years following start of endocrine therapy in these advanced stages. The interval from relapse to prostate carcinoma-related death in patients with the generalized relapse was 9 approximately 21 months, and those in stage D tended to show a a poorer prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)