PC-SPES was, ostensibly, a formulation of eight natural products (seven herbs and one mushroom): Isatis indigotica, Glycyrrhiza glabra ( licorice), Panax pseudo-ginseng, Ganoderma lucidium ( reishi mushroom), Scutellaria baicalensis, Dendranthema morifolium, Robdosia rubescens, and Serenoa repens ( saw palmetto).
The name PC-SPES was derived from the common abbreviation for prostate cancer (PC) and the Latin word spes meaning hope. After its commercial launch in 1996, PC-SPES received considerable interest from the general public and reputable medical researchers as a treatment for prostate cancer. Unfortunately, it turned out to be a fraud.
PC-SPES was not truly a purely herbal product; samples dating back to 1996 were found to contain a form of pharmaceutical estrogen, diethylstilbestrol (DES), as well as indomethacin (an anti-inflammatory medication in the ibuprofen family) and warfarin (a strong blood thinner).19 Samples subsequent to 1999 contained less DES; but they also showed less effectiveness in treating prostate cancer.
There is little doubt that DES is active against prostate cancer, but it presents a variety of risks, including blood clots in the legs. The other two pharmaceutical contaminants might actually reduce this risk (which may be why they were covertly added), but present various risks all on their own. For these reasons, we strongly recommend against using PC-SPES at all.
What Is PC-SPES Used for Today?
The only proposed use of PC-SPES was the treatment of prostate cancer. The formulation was tried at various stages of the disease, and preliminary research indicated that it had potential, particularly for treating prostate cancer that is no longer responsive to hormone therapies. Benefits were reported in the two main types of prostate cancer: hormone-sensitive and hormone-insensitive cancer. However, when the covert addition of pharmaceuticals was discovered, interest in this "herbal" combination ended.
What Is the Scientific Evidence for PC-SPES?
All the results reported in the following paragraphs are consistent with the known effects of hormones related to estrogen, and may be due to the DES present in PC-SPES, rather than the herbal constituents.
Test tube studies of cancer cells found that PC-SPES decreases cell growth, promotes tumor cell death, and reduces PSA (prostate-specific antigen) levels in both hormone-sensitive and hormone-insensitive prostate cancers, and exerts estrogenic effects.1–5,14
In a rat study, PC-SPES treatment reduced the occurrence of prostate cancer tumors, inhibited their growth, and slowed the rate of cancer spread (metastasis) to the lungs.6
In one uncontrolled human study, PC-SPES produced a significant decrease in PSA levels for most of the 33 volunteers tested.7 Similar results were seen in another study of 69 individuals by the same author,8 and a study of 70 people conducted by another researcher.9 Benefits were seen in other uncontrolled trials, as well.10-13
The standard dosage of PC-SPES was 6 to 9 capsules (320 mg each) per day, taken on an empty stomach at least 2 hours before or after meals.
Note: Due to the presence of unlisted pharmaceuticals, PC-SPES should not be used.
It's no surprise that side effects of PC-SPES closely resemble those of estrogen when taken by men for the treatment of prostate cancer;15 it may cause breast or nipple tenderness or swelling, loss of body hair, hot flashes, and loss of libido. Some individuals have also reported leg cramps, nausea and vomiting, and blood clots in the legs.16 Side effects of PC-SPES increase with dosage.
There is one case report of PC-SPES taken at twice the recommended dose causing internal bleeding, presumably due to the presence of warfarin (Coumadin), a strong blood thinner.18
1. Hsieh T, Chen SS, Wang X, et al. Regulation of androgen receptor (AR) and prostate specific antigen (PSA) expression in the androgen-responsive human prostate LNCaP cells by ethanolic extracts of the Chinese herbal preparation, PC-SPES. Biochem Mol Biol Int. 1997;42:535–544.
2. Halicka HD, Ardelt B, Juan G, et al. Apoptosis and cell cycle effects induced by extracts of the Chinese herbal preparation PC SPES. Int J Oncol. 1997;11:437–448.
3. Hsieh TC, Ng C, Chang CC, et al. Induction of apoptosis and down-regulation of bcl-6 in Mutu I cells treated with ethanolic extracts of the Chinese herbal supplement PC-SPES. Int J Oncol. 1998;13:1199–1202.
4. de la Taille A, Hayek OR, Buttyan R, et al. Effects of a phytotherapeutic agent, PC-SPES, on prostate cancer: a preliminary investigation on human cell lines and patients. BJU Int. 1999;84:845–850.
5. de la Taille A, Buttyan R, Hayek O, et al. Herbal therapy PC-SPES: in vitro effects and evaluation of its efficacy in 69 patients with prostate cancer. J Urol. 2000;164:1229–1234.
6. Tiwari RK, Geliebter J, Garikapaty VPS, et al. Anti-tumor effects of PC-SPES, an herbal formulation in prostate cancer. Int J Oncol. 1999;14:713–719.
7. de la Taille A, Hayek OR, Buttyan R, et al. Effects of a phytotherapeutic agent, PC-SPES, on prostate cancer: a preliminary investigation on human cell lines and patients. BJU Int. 1999;84:845–850.
8. de la Taille A, Buttyan R, Hayek O, et al. Herbal therapy PC-SPES: in vitro effects and evaluation of its efficacy in 69 patients with prostate cancer. J Urol. 2000;164:1229–1234.
9. Small EJ, Frohlich MW, Bok R, et al. Prospective trial of the herbal supplement PC-SPES in patients with progressive prostate cancer. J Clin Oncol. 2000;18:3595–3603.
10. Kameda H, Small EJ, Reese DM, et al. A phase II study of PC-SPES, an herbal compound, for the treatment of advanced prostate cancer (PCa) [abstract]. American Society of Clinical Oncology 35th Annual Meeting, Atlanta, Ga; 1999. Abstract 1230.
11. Kameda H, Small EJ, Reese DM, et al. A phase II study of PC-SPES, an herbal compound, for the treatment of advanced prostate cancer (PCa) [abstract]. American Society of Clinical Oncology 35th Annual Meeting, Atlanta,Ga; 1999. Abstract 1230.
12. Pfeifer BL, Pirani JF, Hamann SR, et al. PC-SPES, a dietary supplement for the treatment of hormone-refractory prostate cancer. BJU Int. 2000;85:481–485.
13. Oh WK, George DJ, Hackmann K, et al. Activity of the herbal combination, PC-SPES, in the treatment of patients with androgen-independent prostate cancer. Urology. 2001;57:122–126.
14. DiPaola RS, Zhang H, Lambert GH, et al. Clinical and biologic activity of an estrogenic herbal combination (PC-SPES) in prostate cancer. N Engl J Med. 1998;339:785–791.
15. Moyad MA, Pienta KJ, Montie JE. Use of PC-SPES, a commercially available supplement for prostate cancer, in a patient with hormone-nave disease. Urology. 1999;54:319–324.
16. Kameda H, et al. A phase II study of PC-SPES, an herbal compound, for the treatment of advanced prostate cancer (PCa) [abstract]. American Society of Clinical Oncology 35th Annual Meeting, Atlanta, Ga; 1999. Abstract 1230.
17. Angell M, Kassirer JP. Alternative medicine—the risks of untested and unregulated remedies [editorial]. N Engl J Med. 1998;339:839–841.
18. Weinrobe MC, Montgomery B. Acquired bleeding diathesis in a patient taking PC-SPES [letter]. N Engl J Med. 2001;345:1213–1214.
19. Sovak M, Seligson AL, Konas M, et al. PC-SPES in prostate cancer: an herbal mixture currently containing warfarin and previously diethylstilbestrol and indomethacin. Presented at: 93rd Annual Meeting of the American Association for Cancer Research; April 6-10, 2002; San Francisco, CA.
Last reviewed December 2015 by EBSCO CAM Review Board Last Updated: 12/15/2015