PC-SPES, a dietary supplement for the treatment of hormone-refractory prostate cancer.

OBJECTIVE To assess the effectiveness of PC-SPES, a dietary supplement containing eight herbal extracts, which is a popular alternative therapy among patients with hormone-refractory prostate cancer; anecdotal reports claim that this agent provides relief of metastatic pain, improvements in quality of life and reduction of prostatic specific antigen (PSA) level. PATIENTS AND METHODS Sixteen men treated for advanced metastatic prostate cancer (stage D3) with either orchidectomy or a luteinizing-hormone releasing hormone agonist, with or without anti-androgen, were enrolled into a prospective clinical trial to evaluate the possible toxic and beneficial effects of PC-SPES. After hormone-ablative therapy had failed, and with established disease progression, all patients received supplemental treatment with PC-SPES (2.88 g daily) for 5 months. Hormonal therapy was continued throughout the trial to avoid the known withdrawal effect of anti-androgen on PSA levels. RESULTS The supplemental intake of PC-SPES was associated with significant (P<0.05-0.01) improvements in quality-of-life measures, reductions in patient's pain ratings (P<0.05-0.01), and a decline in PSA levels (P<0.01), with no major side-effects. CONCLUSIONS These results support the anecdotal reports of the beneficial effects of PC-SPES as a comparable alternative to current management regimens in hormone-refractory prostate cancer. However, no conclusions can be drawn about the long-term effects of this new herbal therapy.