Overview
Questions and Answers About PC-SPES
Changes to This Summary (09/21/2007)
General CAM Information
Evaluation of CAM Approaches
Questions to Ask Your Health Care Provider About CAM
To Learn More About CAM

Overview

• PC-SPES is a mixture of 8 herbs that was sold as a dietary supplement to keep the prostate healthy (see Question 1 ¹).



• Some batches of PC-SPES were found to contain prescription medicines. It was taken off the market and is no longer being made (see Question 1 ¹).



• Herbs in PC-SPES have been used in traditional Chinese medicine for many health problems, including prostate problems, for hundreds of years (see Question 2 ²).



• The herbs used in PC-SPES have been reported to help keep cancer cells from growing or help prevent cell damage that can lead to cancer (see Question 3 ³).



• Laboratory and animal studies suggested that PC-SPES might slow the growth of prostate cancer cells, but it is not known if these results were caused by the herbs in PC-SPES, prescription medicines that were found in the mixture, or both (see Question 5 ⁴).



• Clinical trials suggested that PC-SPES lowers PSA (prostate specific antigen) and testosterone levels in humans and has some anticancer effects. It is not known if these results were caused by the herbs in PC-SPES, prescription medicines that were found in the mixture, or both (see Question 6 ⁵).



• The National Center for Complementary and Alternative Medicine plans to do clinical trials of PC-SPES once a standard product is available (see Question 6 ⁵).



• The U.S. Food and Drug Administration has not approved PC-SPES for use in cancer treatment (see Question 8 ⁶).

Questions and Answers About PC-SPES

1. What is PC-SPES?

   PC-SPES is a mixture of herbs that was sold as a complementary and alternative medicine (CAM) treatment for prostate cancer. The mixture contains these 8 herbs:

   • Baikal skullcap (Scutellaria baicalensis)
   • Licorice (Glycyrrhiza glabra or Glycyrrhiza uralensis)
   • Reishi mushroom (Ganoderma lucidum)
   • Isatis (Isatis indigotica)
   • Ginseng (Panax ginseng or Panax pseudoginseng var. notoginseng)
   • Chrysanthemum flowers (Dendranthema morifolium)
   • Rabdosia rubescens (Isodon rubescens)
   • Saw palmetto (Serenoa repens)

   PC-SPES was taken off the market because some batches were found to contain prescription medicines in addition to the herbs. Clinical trials of PC-SPES that were underway were stopped. There are products being sold now as substitutes for PC-SPES, but they are not the same mixture.

2. What is the history of the discovery and use of PC-SPES as a complementary and alternative treatment for cancer?

   Most of the herbs in PC-SPES have been used in traditional Chinese medicine (TCM) for many health problems, including prostate problems, for hundreds of years. A chemist in New York and a doctor/herbalist in China worked together to create the mixture. In 1997, a company was formed to make PC-SPES and sell it in the United States without a prescription. Interest in PC-SPES grew, and researchers began looking at it. Tests found that some batches of PC-SPES contained one or more of the following drugs, which are not found in nature:

   • DES, a type of estrogen made in a lab.
   • Warfarin (Coumadin), a blood-thinner.
   • Indomethacin, a drug used to decrease inflammation.

   Because these drugs are to be used only by prescription and could be harmful to some people, PC-SPES was taken off the market in 2002. The company that made PC-SPES has closed.

3. What is the theory behind the claim that PC-SPES is useful in treating cancer?

   In lab tests, each herb used in PC-SPES has been reported to help keep cancer cells from growing or to help prevent cell damage that can lead to cancer and other diseases.

   PC-SPES was reported to slow the growth of prostate cancer but did not cure it. It is not known how PC-SPES works in the body. Some of the herbs in the mixture contain phytoestrogens, which are estrogen-like substances found in plants. Estrogen can cause the testicles to stop making testosterone, which makes some prostate cancers grow. Patients' responses to PC-SPES were similar to responses to estrogen therapy using DES. The DES found in some batches of PC-SPES, however, may not have been enough to cause all of the estrogen-like effects that were seen in users of the mixture. There is some evidence that the mixture works in a different way than DES does, and that PC-SPES alone (without DES in it) may fight prostate cancer.

   PC-SPES has also shown anticancer effects on prostate cancers that do not depend on testosterone and on other types of cancer. This suggests that PC-SPES may have anticancer qualities other than its estrogen-like effects.

4. How is PC-SPES administered?

   PC-SPES is taken by mouth in capsules.

5. Have any preclinical (laboratory or animal) studies been conducted using PC-SPES?

   Studies of PC-SPES in test tubes and using rats showed that it might keep cancer cells from growing. These studies were done, however, before it became known that some batches of the product contained unlisted prescription medicines. Also, the product was not standardized (different batches of PC-SPES were found to contain different strengths of the herbal ingredients). For these reasons, the results of the lab tests and animal studies are not considered to be good evidence.

   The National Center for Complementary and Alternative Medicine (NCCAM) is doing three laboratory studies using existing PC-SPES supplies. The studies are being done to see how the herbs in PC-SPES might act in the body. Refer to The Future of PC SPES Research Funding by NCCAM ⁷ for more information.

6. Have any clinical trials (research studies with people) of PC-SPES been conducted?

   Clinical trials of PC-SPES had begun before the product was taken off the market. In these trials, PC-SPES was reported to improve quality of life, reduce pain, and lower PSA (prostate specific antigen) levels in patients with prostate cancer. Rising PSA levels can be a sign that prostate cancer is growing.

   After it was learned that some batches of PC-SPES contained prescription medicines, ongoing studies were stopped and previous study results came into question. The responses reported in the studies may have been caused by the prescription medicines that were in the PC-SPES, as well as by the herbal ingredients. Also, since different batches of PC-SPES contained different ingredients, the studies cannot easily be compared.

   NCCAM plans to do clinical trials of PC-SPES once a standard product is available.

7. Have any side effects or risks been reported from PC-SPES?

   Common side effects were the same as those reported with estrogen therapy:

   • Breast swelling and tenderness.
   • Loss of sex drive.
   • Impotence (inability to have an erection).

   There were other, less common, side effects:

   • Blood clots in the legs.
   • Diarrhea.

   PC-SPES may also change the way drugs, including anticancer drugs, work in the body. It may cause drugs to be more or less effective, or cause effects on the body that are not expected.

8. Is PC-SPES approved by the U.S. Food and Drug Administration (FDA) for use as a cancer treatment in the United States?

   The U.S. Food and Drug Administration has not approved PC-SPES for use in cancer treatment. It is not legally sold in the United States.

Changes to This Summary (09/21/2007)

The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.

Editorial changes were made to this summary.

General CAM Information

Complementary and alternative medicine (CAM)—also referred to as integrative medicine—includes a broad range of healing philosophies, approaches, and therapies. A therapy is generally called complementary when it is used in addition to conventional treatments; it is often called alternative when it is used instead of conventional treatment. (Conventional treatments are those that are widely accepted and practiced by the mainstream medical community.) Depending on how they are used, some therapies can be considered either complementary or alternative. Complementary and alternative therapies are used in an effort to prevent illness, reduce stress, prevent or reduce side effects and symptoms, or control or cure disease.

Unlike conventional treatments for cancer, complementary and alternative therapies are often not covered by insurance companies. Patients should check with their insurance provider to find out about coverage for complementary and alternative therapies.

Cancer patients considering complementary and alternative therapies should discuss this decision with their doctor, nurse, or pharmacist as they would any therapeutic approach, because some complementary and alternative therapies may interfere with their standard treatment or may be harmful when used with conventional treatment.

Evaluation of CAM Approaches

It is important that the same rigorous scientific evaluation used to assess conventional approaches be used to evaluate CAM therapies. The National Cancer Institute (NCI) and the National Center for Complementary and Alternative Medicine (NCCAM) are sponsoring a number of clinical trials (research studies) at medical centers to evaluate CAM therapies for cancer.

Conventional approaches to cancer treatment have generally been studied for safety and effectiveness through a rigorous scientific process that includes clinical trials with large numbers of patients. Less is known about the safety and effectiveness of complementary and alternative methods. Few CAM therapies have undergone rigorous evaluation. A small number of CAM therapies originally considered to be purely alternative approaches are finding a place in cancer treatment—not as cures, but as complementary therapies that may help patients feel better and recover faster. One example is acupuncture. According to a panel of experts at a National Institutes of Health (NIH) Consensus Conference in November 1997, acupuncture has been found to be effective in the management of chemotherapy-associated nausea and vomiting and in controlling pain associated with surgery. In contrast, some approaches, such as the use of laetrile, have been studied and found ineffective or potentially harmful.

The NCI Best Case Series Program ⁸, which was started in 1991, is one way CAM approaches that are being used in practice are being investigated. The program is overseen by the NCI’s Office of Cancer Complementary and Alternative Medicine (OCCAM). Health care professionals who offer alternative cancer therapies submit their patients’ medical records and related materials to OCCAM. OCCAM conducts a critical review of the materials and develops follow-up research strategies for approaches deemed to warrant NCI-initiated research.

Questions to Ask Your Health Care Provider About CAM

When considering complementary and alternative therapies, patients should ask their health care provider the following questions:

• What side effects can be expected?
• What are the risks associated with this therapy?
• Do the known benefits outweigh the risks?
• What benefits can be expected from this therapy?
• Will the therapy interfere with conventional treatment?
• Is this therapy part of a clinical trial?
• If so, who is sponsoring the trial?
• Will the therapy be covered by health insurance?

To Learn More About CAM

National Center for Complementary and Alternative Medicine (NCCAM)

The National Center for Complementary and Alternative Medicine (NCCAM) at the National Institutes of Health (NIH) facilitates research and evaluation of complementary and alternative practices, and provides information about a variety of approaches to health professionals and the public.

NCCAM Clearinghouse

Post Office Box 7923 Gaithersburg, MD 20898–7923

Telephone: 1–888–644–6226 (toll free) 301–519–3153 (for International callers)

TTY (for deaf and hard of hearing callers): 1–866–464–3615

Fax: 1–866–464–3616

E-mail: info@nccam.nih.gov

Web site: http://nccam.nih.gov

CAM on PubMed

NCCAM and the NIH National Library of Medicine (NLM) jointly developed CAM on PubMed, a free and easy-to-use search tool for finding CAM-related journal citations. As a subset of the NLM's PubMed bibliographic database, CAM on PubMed features more than 230,000 references and abstracts for CAM-related articles from scientific journals. This database also provides links to the Web sites of over 1,800 journals, allowing users to view full-text articles. (A subscription or other fee may be required to access full-text articles.) CAM on PubMed is available through the NCCAM Web site ⁹. It can also be accessed through NLM PubMed ¹⁰ bibliographic database by selecting the "Limits" tab and choosing "Complementary Medicine" as a subset.

Office of Cancer Complementary and Alternative Medicine

The NCI Office of Cancer Complementary and Alternative Medicine (OCCAM) coordinates the activities of the NCI in the area of complementary and alternative medicine (CAM). OCCAM supports CAM cancer research and provides information about cancer-related CAM to health providers and the general public via the NCI Web site ¹¹.

National Cancer Institute (NCI) Cancer Information Service

U.S. residents may call the NCI Cancer Information Service toll free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 9:00 am to 4:30 pm. Deaf and hearing impaired callers with TTY equipment may call 1-800-332-8615. A trained Cancer Information Specialist is available to answer your questions.

Food and Drug Administration

The Food and Drug Administration (FDA) regulates drugs and medical devices to ensure that they are safe and effective.

Food and Drug Administration

5600 Fishers Lane

Rockville, MD 20857

Telephone: 1–888–463–6332 (toll free)

Web site: http://www.fda.gov/

Federal Trade Commission

The Federal Trade Commission (FTC) enforces consumer protection laws. Publications available from the FTC include:

• Who Cares: Sources of Information About Health Care Products and Services
• Fraudulent Health Claims: Don’t Be Fooled

Consumer Response Center

Federal Trade Commission

CRC-240

Washington, DC 20580

Telephone: 1-877-FTC-HELP (1-877-382-4357) (toll free)

TTY (for deaf and hearing impaired callers): 202-326-2502

Web site: http://www.ftc.gov/

Glossary Terms

A laboratory experiment using animals to study the development and progression of diseases. Animal studies also test how safe and effective new treatments are before they are tested in people.

A mass of blood that forms when blood platelets, proteins, and cells stick together. When a blood clot is attached to the wall of a blood vessel, it is called a thrombus. When it moves through the bloodstream and blocks the flow of blood in another part of the body, it is called an embolus.

A drug that helps prevent blood clots from forming. Also called anticoagulant.

Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

In medicine, a sac of tissue and blood vessels that surrounds an organ, joint, or tumor. A capsule is also a form for medicine that is taken by mouth. It usually has a shell made of gelatin with the medicine inside.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical study.

Forms of treatment that are used in addition to (complementary) or instead of (alternative) standard treatments. These practices generally are not considered standard medical approaches. Standard treatments go through a long and careful research process to prove they are safe and effective, but less is known about most types of CAM. CAM may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation. Also called CAM.

To heal or restore health; a treatment to restore health.

A synthetic form of the hormone estrogen that was prescribed to pregnant women between about 1940 and 1971 because it was thought to prevent miscarriages. DES may increase the risk of uterine, ovarian, or breast cancer in women who took it. It also has been linked to an increased risk of clear cell carcinoma of the vagina or cervix in daughters exposed to DES before birth. Also called diethylstilbestrol.

Frequent and watery bowel movements.

A product that is added to the diet. A dietary supplement is taken by mouth, and usually contains one or more dietary ingredient (such as vitamin, mineral, herb, amino acid, and enzyme). Also called nutritional supplement.

Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

In medicine, the swelling of the penis with blood, causing it to become firm.

A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones. Estrogens can also be made in the laboratory. They may be used as a type of birth control and to treat symptoms of menopause, menstrual disorders, osteoporosis, and other conditions.

An agency in the U.S. federal government whose mission is to protect public health by making sure that food, cosmetics, and nutritional supplements are safe to use and truthfully labeled. The Food and Drug Administration also makes sure that drugs, medical devices, and equipment are safe and effective, and that blood for transfusions and transplant tissue are safe. Also called FDA.

An herb with a root that has been used in some cultures to treat certain medical problems. It may have anticancer effects.

Having to do with plants.

In medicine, refers to the inability to have an erection of the penis adequate for sexual intercourse. Also called erectile dysfunction.

A drug that reduces pain, fever, swelling, and redness. It is also being used to reduce tumor-induced suppression of the immune system and to increase the effectiveness of anticancer drugs. It is a type of nonsteroidal anti-inflammatory drug (NSAID).

Redness, swelling, pain, and/or a feeling of heat in an area of the body. This is a protective reaction to injury, disease, or irritation of the tissues.

Research done in a laboratory. These studies may use test tubes or animals to find out if a drug, procedure, or treatment is likely to be useful. Laboratory studies take place before any testing is done in humans.

A federal agency that uses science to explore complementary and alternative medicine (CAM) practices, trains CAM researchers, and provides authoritative information about CAM to professionals and the public. NCCAM awards grants for research projects, training, and career development in CAM; sponsors conferences, educational programs, and exhibits; studies ways to use proven CAM practices along with conventional medical practice; and supports adding CAM to medical, dental, and nursing school programs. NCCAM is part of the National Institutes of Health. Also called NCCAM.

A mixture of eight herbs that has been sold as a dietary supplement and promoted as a way to keep the prostate healthy and to treat prostate cancer. PC-SPES has been studied in the treatment of prostate cancer, but has been taken off the market in the U.S. because of safety concerns.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

An estrogen-like substance found in some plants and plant products. Phytoestrogens may have anticancer effects.

A doctor's order for medicine or another intervention.

A gland in the male reproductive system. The prostate surrounds the part of the urethra (the tube that empties the bladder) just below the bladder, and produces a fluid that forms part of the semen.

Cancer that forms in tissues of the prostate (a gland in the male reproductive system found below the bladder and in front of the rectum). Prostate cancer usually occurs in older men.

A substance produced by the prostate. It may be found in higher levels in the blood of men who have prostate cancer, benign prostatic hyperplasia, infection or inflammation of the prostate. Also called prostate-specific antigen.

The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

In medicine, an improvement related to treatment.

A shrub that is a member of the palm tree family. An extract made from the berries of this shrub has been studied in the treatment of certain urinary and prostate disorders. The scientific name is Serenoa repens.

A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

One of two egg-shaped glands inside the scrotum that produce sperm and male hormones. Also called testis.

A hormone made mainly in the testes (part of the male reproductive system). It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. Testosterone may also be made in the laboratory and is used to treat certain medical conditions.

Treatment.

A medical system that has been used for thousands of years to prevent, diagnose, and treat disease. It is based on the belief that qi (the body's vital energy) flows along 20 meridians (channels) throughout the body and keeps a person’s spiritual, emotional, mental, and physical health in balance. Traditional Chinese medicine aims to restore the body’s balance and harmony between the natural opposing forces of yin and yang, which can block qi and cause disease. Traditional Chinese medicine includes acupuncture, diet, herbal therapy, meditation, physical exercise, and massage. Also called Oriental medicine and TCM.

A drug that prevents blood from clotting. It belongs to the family of drugs called anticoagulants (blood thinners).