PC-SPES: a herbal therapy for the treatment of hormone refractory prostate cancer.

In this review the authors consider the commercially available herbal product PC-SPES. This is a combination of eight different herbs marketed for its effects of reducing prostate specific antigen (PSA) levels, improving pain, and enhancing the quality of life of those with hormone refractory prostate cancer. The evidence for these claims does not appear to be as conclusive as reported by the manufactures of this product. There also appears to be a significant risk of deep vein thrombosis (DVT) in those treated with PC-SPES. There have been 116 clinical and laboratory based studies of PC-SPES published to date, but there have been no randomised controlled trials conducted. Many of these studies contain very few patients, thus making the drawing of conclusions difficult. Despite this lack of information, there still remains a large patient group taking this supplement, therefore caution should be advised in the usage of PC-SPES in the treatment of hormone refractory prostate cancer.