However, researchers caution that the herbal combination contains potent estrogenic substances which have side effects similar to pharmaceutical doses of estrogen such as, blood clots, breast tenderness, and loss of libido. We have rigorously demonstrated the potent pharmacological activity of an unregulated herbal remedy and uncovered the mechanisms to explain its efficacy and untoward side effects. Previous anecdotal reports suggested that PC-SPES, long used in China and available in the United States, provides prostate cancer patients much needed relief. Men also reported that bone pain, which often accompanies the disease, was alleviated. Prior studies have demonstrated that saw palmetto, a PC SPES component, can inhibit an enzyme involved in testosterone metabolism and is used commonly to alleviate symptoms of benign prostate hyperplasia.
Most patients receive testosterone-lowering drugs that initially control the disease.
Each patient enrolled was evaluated for serum testosterone concentrations. The study found that PC-SPES reduced PSA and testosterone levels in all patients. In the laboratory, PC-SPES was found to behave like a potent estrogen in yeast systems engineered to accurately measure such effects. Since large doses of estrogen are known to lower testosterone and also have untoward side effects including blood clots, loss of libido and breast tenderness, the efficacy and safety of this herbal combination should be given the same consideration. Established in 1990, The Cancer Institute of New Jersey is the state's only National Cancer Institute designated cancer center.