[Clinical usefulness of chlormadinone acetate as an alternative antiandrogen therapy for prostate cancer relapse after combined androgen blockade therapy].

We prospectively studied the usefulness of chlormadinone acetate (CMA) as an alternative therapy for prostate cancer relapse after combined androgen blockade (CAB) therapy. Sixteen patients with relapsed prostate cancer after treatment with CAB, including surgical or medical castration and nonsteroidal antiandrogens, 80 mg bicalutamide daily or 375 mg flutamide daily, were enrolled. After discontinuing the antiandrogen for evaluating the patient for the antiandrogen withdrawal syndrome, we administered 100 mg CMA daily as alternative antiandrogen and estimated its effect.