Key Points for This Section

Avoiding risk factors and increasing protective factors may help prevent cancer. The following risk factors may increase the risk of prostate cancer: Age Family history of prostate cancer Race Hormones Folic acid Dairy and calcium The following protective factors may decrease the risk of prostate cancer: Folate Finasteride The following have been proven not to affect the risk of prostate cancer, or their effects on prostate cancer risk are not known: Selenium and vitamin E Diet Multivitamins Lycopene Cancer prevention clinical trials are used to study ways to prevent cancer. New ways to prevent prostate cancer are being studied in clinical trials.

Avoiding risk factors and increasing protective factors may help prevent cancer.

Avoiding cancer risk factors such as smoking, being overweight, and lack of exercise may help prevent certain cancers. Increasing protective factors such as quitting smoking, eating a healthy diet, and exercising may also help prevent some cancers. Talk to your doctor or other health care professional about how you might lower your risk of cancer.

The following risk factors may increase the risk of prostate cancer:

Age

Prostate cancer is rare in men younger than 50 years of age. The chance of developing prostate cancer increases as men get older.

Family history of prostate cancer

A man whose father, brother, or son has had prostate cancer has a higher-than-average risk of prostate cancer.

Race

African-American men are more likely than white men to develop prostate cancer and die from it.

Hormones

The prostate needs male hormones to work the way it should. The main male sex hormone is testosterone. Testosterone helps the body develop and maintain male sex characteristics.

Testosterone is changed into dihydrotestosterone (DHT) by an enzyme in the body. DHT is important for normal prostate growth but can also cause the prostate to get bigger and may play a part in the development of prostate cancer.

Folic acid

A 10-year study showed that the risk of prostate cancer was increased in men who took supplements of folic acid (a nutrient in the vitamin B complex).

Dairy and calcium

A diet high in dairy foods and calcium may cause a small increase in the risk of prostate cancer.

The following protective factors may decrease the risk of prostate cancer:

Folate

A 10-year study showed that prostate cancer risk was lowered in men who had enough folate in their diets.

Finasteride

The Prostate Cancer Prevention Trial (PCPT) studied whether the drug finasteride can prevent prostate cancer in healthy men 55 years of age and older. Finasteride is a drug that blocks the enzyme that changes testosterone into dihydrotestosterone (DHT). DHT may play a part in the development of prostate cancer.

The prevention study showed there were fewer prostate cancers in the group of men who took finasteride compared to the group that did not take it. However, the men in the finasteride group who did have prostate cancer had more aggressive tumors. The number of deaths from prostate cancer was the same in both groups.

The following have been proven not to affect the risk of prostate cancer, or their effects on prostate cancer risk are not known:

Selenium and vitamin E

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) studied whether taking vitamin E and selenium (a mineral) will prevent prostate cancer. The selenium and vitamin E were taken separately or together by healthy men 55 years of age and older (50 years of age and older for African-American men). The study showed that selenium and vitamin E did not decrease the risk of prostate cancer.

Diet

It is not known if decreasing fat or increasing fruits and vegetables in the diet helps decrease the risk of prostate cancer or death from prostate cancer.

Multivitamins

Regular use of multivitamins has not been proven to increase the risk of early or localized prostate cancer.

Lycopene

Some studies have shown that a diet high in lycopene may be linked to a decreased risk of prostate cancer, but other studies have not. It has not been proven that taking lycopene supplements decreases the risk of prostate cancer.

Cancer prevention clinical trials are used to study ways to prevent cancer.

Cancer prevention clinical trials are used to study ways to lower the risk of developing certain types of cancer. Some cancer prevention trials are conducted with healthy people who have not had cancer but who have an increased risk for cancer. Other prevention trials are conducted with people who have had cancer and are trying to prevent another cancer of the same type or to lower their chance of developing a new type of cancer. Other trials are done with healthy volunteers who are not known to have any risk factors for cancer.

The purpose of some cancer prevention clinical trials is to find out whether actions people take can prevent cancer. These may include eating fruits and vegetables, exercising, quitting smoking, or taking certain medicines, vitamins, minerals, or food supplements.

New ways to prevent prostate cancer are being studied in clinical trials.

Clinical trials are taking place in many parts of the country. Information about clinical trials can be found in the Clinical Trials section of the NCI Web site ¹. Check for clinical trials in NCI's PDQ Cancer Clinical Trials Registry for prostate cancer prevention trials ² that are accepting patients.

Glossary Terms

A quickly growing cancer.

A mineral needed for healthy teeth, bones, and other body tissues. It is the most common mineral in the body. A deposit of calcium in body tissues, such as breast tissue, may be a sign of disease.

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a 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. Also called malignancy.

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.

The things a person eats and drinks.

A hormone made from testosterone in the prostate, testes, and certain other tissues. It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. High amounts of dihydrotestosterone may increase the growth of prostate cancer and make it harder to treat. Also called androstanolone and DHT.

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.

A protein that speeds up chemical reactions in the body.

A drug used to reduce the amount of male hormone (testosterone) produced by the body.

A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Folate helps to make red blood cells. It is found in whole-grain breads and cereals, liver, green vegetables, orange juice, lentils, beans, and yeast. Folate is water-soluble (can dissolve in water) and must be taken in every day. Not enough folate can cause anemia (a condition in which the number of red blood cells is below normal), diseases of the heart and blood vessels, and defects in the brain and spinal cord in a fetus. Folate is being studied with vitamin B12 in the prevention and treatment of cancer. Also called folic acid.

A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Folic acid helps to make red blood cells. It is found in whole-grain breads and cereals, liver, green vegetables, orange juice, lentils, beans, and yeast. Folic acid is water-soluble (can dissolve in water) and must be taken in every day. Not enough folic acid can cause anemia (a condition in which the number of red blood cells is below normal), diseases of the heart and blood vessels, and defects in the brain and spinal cord in a fetus. Folic acid is being studied with vitamin B12 in the prevention and treatment of cancer. Also called folate.

One of many chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be made in the laboratory.

Restricted to the site of origin, without evidence of spread.

A red pigment found in tomatoes and some fruits. It is an antioxidant and may help prevent some types of cancer.

Refers to the practices and procedures used for the prevention, treatment, or relief of symptoms of a diseases or abnormal conditions. This term may also refer to a legal drug used for the same purpose.

In medicine, a mineral is a nutrient that is needed in small amounts to keep the body healthy. Mineral nutrients include the elements calcium, magnesium, and iron.

A chemical compound (such as protein, fat, carbohydrate, vitamin, or mineral) contained in foods. These compounds are used by the body to function and grow.

Being too heavy for one’s height. Excess body weight can come from fat, muscle, bone, and/or water retention. Being overweight does not always mean being obese.

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.

In medicine, action taken to decrease the chance of getting a disease or condition. For example, cancer prevention includes avoiding risk factors (such as smoking, obesity, lack of exercise, and radiation exposure) and increasing protective factors (such as getting regular physical activity, staying at a healthy weight, and having a healthy diet).

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.

Something that may decrease the chance of getting a certain disease. Some examples of protective factors for cancer are getting regular physical activity, staying at a healthy weight, and having a healthy diet.

Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.

A mineral that is needed by the body to stay healthy. It is being studied in the prevention and treatment of some types of cancer. Selenium is a type of antioxidant.

Adding nutrients to the diet.

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.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.

A nutrient that the body needs in small amounts to function and stay healthy. Sources of vitamins are plant and animal food products and dietary supplements. Some vitamins are made in the human body from food products. Vitamins are either fat-soluble (can dissolve in fats and oils) or water-soluble (can dissolve in water). Excess fat-soluble vitamins are stored in the body’s fatty tissue, but excess water-soluble vitamins are removed in the urine. Examples are vitamin A, vitamin C, and vitamin E.

A compound containing several or all of a group of vitamins and nutrients that the body needs in very small amounts to function and stay healthy. The B vitamins in the vitamin B complex include thiamine, riboflavin, niacin (nicotinic acid), niacinamide (nicotinamide), the vitamin B6 group (including pyridoxine, pyridoxal, pyridoxamine), biotin, pantothenic acid, folic acid, and vitamin B12. Aminobenzoic acid, inositol, and choline are sometimes included as part of the vitamin B complex. The vitamin B complex is water-soluble (can dissolve in water) and is found in yeast, seeds, eggs, liver, meat, and vegetables. Members of the vitamin B complex are being studied in the prevention and treatment of some types of cancer.

A nutrient that the body needs in small amounts to function and stay healthy. Vitamin E helps prevent cell damage caused by free radicals (highly reactive chemicals). It is fat-soluble (can dissolve in fats and oils) and is found in seeds, nuts, leafy vegetables, and vegetable oils. Not enough vitamin E can result in infertility (the inability to produce children). It is being studied in the prevention and treatment of some types of cancer. Vitamin E is a type of antioxidant.