Intermittent endocrine therapy of prostate cancer.

Abstract

Permanent androgen suppression is the therapy of choice in the treatment of advanced prostate cancer. Intermittent androgen deprivation (IAD) through reversible medical castration results, hypothetically, in androgen-induced differentiation of tumor stem cells with recovery of the apoptotic potential. The cycle of periods with and without androgen withdrawal should delay androgen-independent tumor progression. In initial pilot studies, the IAD concept proved less successful in patients with a high tumor burden than in those with locally advanced prostatic cancer. In our own pilot study, patients with a low tumor burden could be successfully treated with IAD. Until further studies have been completed, the therapeutic concept with IAD should be regarded as experimental. Only further prospective randomized phase III studies will be able to establish whether survival and quality of life of patients with prostatic cancer can be considerably improved by IAD.