Testosterone recovery and changes in bone mineral density after stopping long-term luteinizing hormone-releasing hormone analogue therapy in osteoporotic patients with prostate cancer.

OBJECTIVE: To investigate the rate of testosterone recovery and changes in bone mineral density in patients found to be osteoporotic while receiving luteinizing hormone-releasing hormone (LHRH) analogues after changing to antiandrogen monotherapy in an attempt to reduce further demineralization. PATIENTS AND METHODS: Fifteen patients receiving LHRH analogue therapy for > or = 1 year were identified as osteoporotic by distal forearm dual X-ray densitometry. They were then converted to antiandrogen monotherapy, and prostate specific-antigen (PSA) and total testosterone monitored at 3-monthly intervals. The forearm densitometry was repeated at 1 year. RESULTS: All patients had some testosterone recovery; the mean (range) duration to initial detectable testosterone was 12.8 (6-22) months. Six patients had a normal testosterone level after a mean of 17.5 (14-30) months. In the year after stopping LHRH analogue therapy the mean bone mineral density (t-score) decreased by 7.2%. CONCLUSIONS: Osteoporotic patients, after stopping LHRH analogues, continue to have suppressed levels of testosterone which have a detrimental effect on bone mineral density. We therefore would not advocate conversion to antiandrogen monotherapy to improve bone density, and suggest alternative therapeutic intervention e.g. bisphosphonate therapy, for these patients.