Men with advanced prostate cancer may be given therapy to stop their production of testosterone, which may drive tumor growth. However, androgen deprivation therapy, or ADT, appears to trigger a rapid loss of bone mineral density (BMD), researchers report.
Dr. Susan L. Greenspan of the University of Pittsburgh and colleagues note in the Journal of Clinical Endocrinology and Metabolism that although bone loss is associated with ADT, little is known about when this may occur.
To investigate further, the researchers studied 152 men with prostate cancer and healthy “controls.” In all, 30 of the cancer patients had had ADT for less than 6 months, 50 had received it for 6 months or more, and the remaining 72 were not receiving ADT.
At 12 months, depending on the site of measurement, BMD loss ranged from 1 to 4 percent in men recently started on ADT. In particular, the loss in BMD at the wrist was 3.3 percent in these patients compared to just 2 percent in those patients had been on therapy for longer.
No significant reduction in BMD was seen in patients not undergoing ADT or controls.
Because the rate of bone loss “is maximal in the first year after androgen suppression is initiated,” the researchers suggest that drug therapy aimed at stopping the resorption of bone “may be most effective if prescribed during this period.”