Prostate Cancer Prevention
KEY POINTS
- 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
- Vitamin E
- Folic acid
- Dairy and calcium
- The following protective factors may decrease the risk of prostate cancer:
- Folate
- Finasteride and Dutasteride
- 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 may help prevent certain cancers. Risk factors include smoking, being overweight, and not getting enough exercise. Increasing protective factors such as quitting smoking 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
Prostate cancer occurs more often in African-American men than in white men. African-American men with prostate cancer are more likely to die from the disease than white men with prostate cancer.
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.
Vitamin E
The Selenium and Vitamin E Cancer Prevention Trial (SELECT) found that vitamin E taken alone increased the risk of prostate cancer. The risk continued even after the men stopped taking vitamin E.
Folic acid
Folate is a kind of vitamin B that occurs naturally in some foods, such as green vegetables, beans and orange juice. Folic acid is a man-made form of folate that is found in vitamin supplements and fortified foods, such as whole-grain breads and cereals. A 10-year study showed that the risk of prostate cancer was increased in men who took 1 milligram (mg) supplements of folic acid. However, the risk of prostate cancer was lower in men who had enough folate in their diets.
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
Folate is a kind of vitamin B that occurs naturally in some foods, such as green vegetables, beans and orange juice. Folic acid is a man-made form of folate that is found in vitamin supplements and fortified foods, such as whole-grain breads and cereals. A 10-year study showed that the risk of prostate cancer was lower in men who had enough folate in their diets. However, the risk of prostate cancer was increased in men who took 1 milligram (mg) supplements of folic acid.
Finasteride and Dutasteride
Finasteride and dutasteride are drugs used to lower the amount of male sex hormones made by the body. These drugs block the enzyme that changes testosterone into dihydrotestosterone (DHT). Higher than normal levels of DHT may play a part in developing prostate cancer. Taking finasteride or dutasteride has been shown to lower the risk for prostate cancer, but it is not known if these drugs lower the risk of death from prostate cancer.
The Prostate Cancer Prevention Trial (PCPT) studied whether the drug finasteride can prevent prostate cancer in healthy men 55 years of age and older. This prevention study showed there were fewer prostate cancers in the group of men that took finasteride compared with the group of men that did not. Also, the men who took finasteride who did have prostate cancer had more aggressive tumors. The number of deaths from prostate cancer was the same in both groups. Men who took finasteride reported more side effects compared with the group of men that did not, including erectile dysfunction, loss of desire for sex, and enlarged breasts.
The Reduction by Dutasteride of Prostate Cancer Events Trial (REDUCE) studied whether the drug dutasteride can prevent prostate cancer in men aged 50 to 75 years at higher risk for the disease. This prevention study showed there were fewer prostate cancers in the group of men who took dutasteride compared with the group of men that did not. The number of less aggressive prostate cancers was lower, but the number of more aggressive prostate cancers was not. Men who took dutasteride reported more side effects than men who did not, including erectile dysfunction, loss of desire for sex, less semen, and gynecomastia (enlarged breasts).
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 taking selenium alone or selenium and vitamin E together 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. In the PCPT trial, certain fatty acids increased the risk of high-grade prostate cancer while others decreased the risk of high-grade prostate cancer.
Multivitamins
Regular use of multivitamins has not been proven to increase the risk of early or localized prostate cancer. However, a large study showed an increased risk of advanced prostate cancer among men who took multivitamins more than seven times a week.
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 website. Check NCI’s list of cancer clinical trials for prostate cancer prevention trials that are accepting patients.