For men with newly diagnosed prostate cancer, treatment with estrogen delivered by a skin patch not only has the desirable effect of lowering male hormone levels but also prevents bone loss, UK researchers report.

As they report in the Journal of Urology, the estrogen patch may improve bone mineral density, thereby lowering the risk of fractures resulting from osteoporosis.

Conventional methods of lowering male hormones (androgens) in order to treat prostate cancer lead to a progressive decline in bone mineral density and accelerated osteoporosis, among other things.

Recently, Dr. Paul D. Abel and colleagues from Imperial College and Hammersmith Hospitals NHS Trust in London showed that estrogen patch therapy is an effective alternative to standard treatment by providing a well-tolerated anti-androgen effect.

Their latest study shows that the estrogen patch also has a significant beneficial effect on bone health, Abel told Reuters Health.

In the study, 20 men with advanced prostate cancer, who had not previously been treated with androgen deprivation, applied two transdermal estradiol patches to the shoulder area, changing them two or three times weekly.

Bone mineral density “increased with time,” the team reports.

After a year, average bone mineral density had increased by 3.60 percent in the spine and 1.90 percent in the hip. Four of 12 areas of bone thinning showed improvements.

All patients also had a significant drop in their PSA levels. The average reduction was 95 percent, which is at least as good as traditional therapy.

Based on this study and others, “large randomized trials are justified to address the issues about the relative merits of the various therapies, which seem about equivalent in efficacy, but have markedly different side-effect profiles,” Abel said.

His team’s results show that estrogen patch treatment can be used as the sole therapy for prostate cancer, Abel pointed out, “and is about 10 percent the cost of conventional therapy alone, and correspondingly even cheaper than combination therapy,”

SOURCE: Journal of Urology, December 2004.