Prostate cancer hormone therapy triggers bone loss

NEW YORK (Reuters Health) – 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.”

SOURCE: Journal of Clinical Endocrinology and Metabolism,
December 2005.