Phytotherapy has won popular appreciation world-wide in the last few years with advocates proposing that herbs have the advantage of being reasonably effective, of producing fewer side-effects, and of being less costly compared with standard pharmaceutical therapies. PC-SPES is a combination of eight herbs effective for the treatment of prostate cancer patients, including androgen-dependent and androgen-independent cancers, with an overall improvement of morbidity and immune status, even in those in whom conventional therapy has failed. The preparation is estrogenic; however, its therapeutic activity is not only due to its estrogenicity, and the mechanism of action seems to be complicated. The constituent herbs of the preparation possess antitumor, antioxidant, immunomodulatory and anti-inflammatory activities, all of which may contribute to the therapeutic action of PC-SPES on prostate cancer. Further studies are needed to ascertain its long-term effect and safety, and to identify the active compounds an...