Patch-delivered estrogen treats prostate cancer with fewer side effects

Researchers in the U.K. have found that an estrogen patch is an effective way to treat prostate cancer compared with side effects-laden hormone injections and pills.

Scientists at Imperial College London completed a Phase II trial in 254 men with locally advanced prostate cancer, in which they pitted the patch against the current standard-of-care injection, LHRHa. The purpose of introducing estrogen as a treatment is to suppress the converse hormone testosterone, which feeds prostate tumors, in a process that has been proven to shrink the tumors or slow their growth.

The problem with both the injection and the oral version of estrogen is that they come with a bevy of serious side effects, including a higher risk of heart problems and stroke, as well as hot flashes, osteoporosis, bone fractures and diabetes, according to Cancer Research UK. By delivering the hormone through the skin, the patches showed a similar ability to quell testosterone with less heart and blood-clotting issues, likely because the estrogen bypassed the liver, said the study's author, Ruth Langley.

The patch, already used to treat menopause in women, will soon enter Phase III trials for treatment of prostate cancer, and the researchers expect to have results by the end of the year.

- here's the Cancer Research UK release
- and the abstract in Lancet Oncology