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Other common name(s): PC PLUS, Prostasol

Scientific/medical name(s): none


PC-SPES was a formula consisting of a combination of 8 herbs that contained a range of plant chemicals including flavonoids, alkanoids, polysaccharides, amino acids, and trace minerals such as selenium, calcium, magnesium, zinc, and copper. The 8 herbs used were chrysanthemum, isatis, licorice, Ganoderma lucidum, Panax pseudo-ginseng, Rabdosia rubescens, saw palmetto, and skullcap (see Licorice, and Saw Palmetto ), although other compounds were found in the formula.

PC stands for prostate cancer, and SPES is the Latin word for hope. PC-SPES was removed from the US market in February 2002. The US Food and Drug Administration (FDA) issued a warning for people to stop using the product because PC-SPES capsules were found to contain prescription drugs that could cause serious health problems.

Since then, several new herbal products for prostate cancer have been developed. The 2 most popular of these are PC-HOPE and PC-CARE. A similar product is Prostasol, previously sold as PC-PLUS. PC-HOPE includes the following ingredients: magnesium, sterolins, quercetin, “proprietary blend”, Reishi (as Ganoderma Lucidum), Baikal Skullcap (as Scutellaria Baicalensis), Rabdosia (as Rabdosia rubescens Hara). Dyer's Woad (as Isatis Indigotica Fortune), Mum (as Dendranthema Morifolium Tzelev), Saw Palmetto (as Serenoa Repens), San-Qi Ginseng (as Panax Notoginseng), and Licorice (as Glycyrrhiza Glabra L). The company that produces this product recommends starting with 2 to 6 tablets daily, and gradually reducing the dose over a period of months.

The ingredients of PC-CARE are listed as: "Proprietary Blend", Reishi, Balkal Skullcap, Rabdosia Rubescens, Isatis indigotica, Chrysanthemum, Saw Palmetto, Rye, and Licorice. The company producing this product recommends 3 tablets daily.


Several carefully designed clinical trials found that PC-SPES was an effective treatment for patients with prostate cancer, including some whose cancer did not respond to conventional hormone therapy. Common side effects included breast enlargement and tenderness, hot flashes, and decreased libido. Blood clots were a less common but more serious side effect. However, because the production process for PC-SPES did not offer adequate protection against contamination, this product is no longer available.

Newer products, such as PC-HOPE and PC-CARE, contain many of the same ingredients as PC-SPES. However, because of limitations in the way herbal products are regulated in the United States, patients and clinicians cannot make any assumptions regarding the purity, safety, or effectiveness of these new products. More research is needed to evaluate them.

How is it promoted for use?

PC-SPES was promoted as a treatment for prostate cancer. Proponents claimed that the herbal preparation could prevent or delay the recurrence of prostate cancer, inhibit the growth of prostate tumors, lengthen the survival time of prostate cancer patients, improve the effectiveness of conventional treatments, and delay the need for treatment with chemotherapy.

PC-HOPE, PC-CARE, and Prostasol (previously known as PC-PLUS) are promoted in similar ways.

What does it involve?

These herbal formulations for prostate cancer treatment come in capsules and are taken daily, in varying dosages. PC-SPES is no longer produced. PC-HOPE and PC-CARE are available in health food stores, from some nutritionists, and directly from manufacturers.

What is the history behind it?

PC-SPES was developed in the early 1990s by a chemist named Sophie Chen, PhD, who claimed to have developed the formula by integrating modern science and ancient Chinese herbal wisdom. By the mid 1990s, the formula was widely promoted in the United States and was named PC-SPES. Production of PC-SPES was stopped in 2002 when it was found to be contaminated with varying amounts of 3 prescription drugs: warfarin (an anticoagulant), diethylstilbesterol (DES, an estrogen-like hormone), and indomethacin (an anti-inflammatory drug). PC-HOPE, PC-CARE, and Prostasol became popular after production of PC-SPES was halted.

What is the evidence?

PC-SPES has been carefully evaluated in several clinical trials. In virtually all of these studies, PC-SPES was found to be effective in reducing blood levels of prostate-specific antigen (PSA), a protein secreted by cancerous prostate cells that is widely used by doctors as a measure of whether prostate cancer is responding to treatment or continuing to grow and spread. Several studies also observed shrinking in tumors following treatment.

A randomized clinical trial comparing PC-SPES and diethylstilbesterol (DES, an estrogen-like hormone) was started before PC-SPES’s problems with contamination were known, and results were published in 2004. DES is sometimes used as a hormonal treatment for prostate cancer that is no longer responding to treatments that block production of male hormones or the effects of those hormones. Although some of the PC-SPES tablets used in the study were later found to be contaminated with DES or other estrogenic prescription drugs, the herbal product was actually more effective than DES pills in lowering blood PSA levels and in delaying growth of the cancer. The men receiving PC-SPES were at lower risk for blood clots than those taking DES.

Prior to its removal from the market, laboratory studies of PC-SPES looked at how its ingredients blocked the growth of prostate cancer cells. Substances from some of the ingredients acted as phytoestrogens (estrogen-like substances found in plants) and blocked the growth of prostate cancer cells. Prostate cancer cells are fueled by androgens (male hormones) and slowed by estrogens (female hormones). Some ingredients may have helped to activate the immune system. Still others acted in ways not yet completely understood, but which appeared to involve mechanisms other than acting as estrogens.

A few laboratory studies of PC-HOPE and PC-CARE have been published, and these studies suggest they are active against prostate cancer cells. Two European clinical studies of PC-HOPE suggest it may improve patients’ quality of life and lower their PSA levels. These 2 studies are summarized in press releases on the Internet, but as of mid-2008 the detailed results had not yet been published in medical journals.

Before PC-SPES was removed from the market, many prostate specialists considered it a reasonable option for treating men whose prostate cancers are androgen-independent, meaning they are no longer responding to treatments that block production or activity of male hormones. PC-SPES was not recommended for cancers that were still responding to conventional hormonal treatments or for men with localized prostate cancer that could be treated with surgery or radiation therapy.

The role of newer herbal formulations currently remains uncertain, because US laws permit companies to sell these products without providing detailed information on safety and effectiveness (as would be required for new drugs). It will probably take a few years for prostate cancer researchers to complete clinical studies of PC-HOPE and PC-CARE similar to those they had done on PC-SPES.

Are there any possible problems or complications?

This product is sold as a dietary supplement in the United States. Unlike companies that produce drugs (which must provide the FDA with results of detailed testing showing their product is safe and effective before the drug is approved for sale), the companies that make supplements do not have to show evidence of safety or health benefits to the FDA before selling their products. Supplement products without any reliable scientific evidence of health benefits may still be sold as long as the companies selling them do not claim the supplements can prevent, treat, or cure any specific disease. Some such products may not contain the amount of the herb or substance that is written on the label, and some may include other substances (contaminants). Though the FDA has written new rules to improve the quality of manufacturing processes for dietary supplements and the accurate listing of supplement ingredients, these rules do not take full effect until 2010. And, the new rules do not address the safety of supplement ingredients or their effects on health when proper manufacturing techniques are used.
Most such supplements have not been tested to find out if they interact with medicines, foods, or other herbs and supplements. Even though some reports of interactions and harmful effects may be published, full studies of interactions and effects are not often available. Because of these limitations, any information on ill effects and interactions below should be considered incomplete.

Side effects associated with the use of PC-SPES included increased breast size and nipple tenderness or pain and a reduced sex drive. There was also an increased risk of blood clots, which are potentially fatal. Since PC-HOPE, Prostasol, and PC-CARE are reported to be quite similar to PC-SPES, side effects may also be similar.

As with all herbs, allergic reactions are possible. In addition, the potential interactions between herbs and other drugs and herbs should be considered. Some of these combinations may be dangerous. Always tell your doctor and pharmacist about any herbs you are taking. Relying on this type of treatment alone and avoiding or delaying conventional medical care for cancer may have serious health consequences.

Additional resources

More information from your American Cancer Society

The following information on complementary and alternative therapies may also be helpful to you. These materials may be found on our Web site (www.cancer.org) or ordered from our toll-free number (1-800-ACS-2345).

Dietary Supplements: What Is Safe?

The ACS Operational Statement on Complementary and Alternative Methods of Cancer Management

Complementary and Alternative Methods and Cancer

Placebo Effect

Learning About New Ways to Treat Cancer

Learning About New Ways to Prevent Cancer


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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.

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PC-SPES. Memorial Sloan-Kettering Cancer Center Web site. Accessed at www.mskcc.org/mskcc/html/69326.cfm on June 6, 2008.

PC-SPES (PDQ). National Cancer Institute Web site. Accessed at www.nci.nih.gov/cancertopics/pdq/cam/pc-spes/HealthProfessional/page1 on June 6, 2008.

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Note: This information may not cover all possible claims, uses, actions, precautions, side effects or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for consultation with your doctor, who is familiar with your medical situation.

Last Medical Review: 11/28/2008
Last Revised: 11/28/2008