Chlormadinone acetate withdrawal syndrome under combined androgen blockade for advanced prostate cancer

Between July 1991 and December 1994 at Tsukuba Gakuen Hospital, we treated 19 consecutive men with advanced adenocarcinoma of the prostate (five at stage C, four at stage D1 and 10 at stage D2). Of these, 14 patients underwent castration (two patients) or received LH-RH analogue (12 patients) plus chlormadinone acetate for combined androgen blockade. We report three representative cases of sequential prostate specific antigen (PSA) elevation following initial response to this combined androgen blockade. Discontinuation of chlormadinone acetate resulted in decline of the serum PSA level. This suggests that trial chlormadinone acetate withdrawal in patients showing increasing levels of PSA during combined androgen blockade should be considered before initiation of alternative treatment.