Why hormone therapy for prostate cancer fails

A new study found that some of the drugs given to many men during their treatment against prostate cancer can actually spur some cancer cells to grow.

The findings may help explain a phenomenon that has bedeviled patients for decades. According to statistics, hormone therapy, a common treatment for men with advanced prostate cancer, generally keeps the cancer at bay for a year or two. But then, for reasons scientists have never understood, the treatment fails in patients whose disease has spread - the cancer begins to grow again, at a time when patients have few treatment options left.

The findings were published online this week in a pair of papers in the Proceedings of the National Academy of Sciences.