Changes in testosterone, prolactin and estradiol levels were evaluated vis-a-vis outcome and different patterns of androgen suppression--continuous androgen blockade or intermittent therapy--for prostate cancer patients. There was a significant difference between pre- (3.4 +/- 0.5 mM/l) and post- (1.0 +/- 0.3 mM/l) treatment levels of testosterone in cases of tumor progression and that in patients with positive response--(9.1 +/- 0.6 mM/l) and (4.3 +/- 0.4 mM/l), respectively. Relatively low levels of testosterone involved tumor progression. Prolactin level was significantly higher in patients with multiple distant metastases--(18.6 +/- 1.2 microg/l) and isolated foci--(9.5 +/- 0.8 microg/l) while tumor progression was associated with enhancing correlation with PSA concentration. It was established that prolactin level can be used as a criterion for resumption or discontinuation of intermittent therapy. Estradiol dynamics was similar to that of prolactin. The difference between pre- (172.9 +/- 9.8 pM/l) and post- (246.5 +/- 12.8 pM/l) treatment levels of estradiol in cases of tumor progression was significantly higher than that in patients with positive response (85.0 +/- 3.8 pM/l) and (76.9 +/- 4.4 pM/l), respectively.