Prostate Cancer Risk Factors
In general, all men are at risk for prostate cancer. However, there are specific risk factors that increase the likelihood that certain men will develop the disease, including the following:
- age
Age is a risk factor for prostate cancer, especially men age 50 and older. Nearly two-thirds of all prostate cancers are diagnosed in men over the age of 65. - race
Prostate cancer is more common among African American men than it is among Caucasian American men. Japanese and Chinese men native to their country have the lowest rates of prostate cancer. When Chinese and Japanese men immigrate to the US, they have an increased risk and mortality rate from prostate cancer, when compared to their native populations. In Japan, the incidence of prostate cancer has increased as Western diets and lifestyles have been adopted. - diet
Epidemiological data suggests that the diet consumed in Western industrialized countries may be one of the most important contributory factors for developing prostate cancer.- fat
Studies suggest that men who eat a high-fat diet, especially if it is high in animal fat, may have a greater chance of developing prostate cancer. - fruits and vegetables
Diets high in fruits and vegetables may lower prostate cancer risk, although it is not clear which nutrient(s) may be responsible for this. Researchers at Stanford have shown that curciferous vegetables like broccoli might protect against prostate cancer through a chemical called sulforaphane, found at a high level in these vegetables. - vitamin E and selenium
Vitamin E, an antioxidant, combined with selenium, has been shown to inhibit tumor growth in laboratory animals. However, a large clinical trial found no reduced risk in people who took vitamin E or selenium supplements (or both). - carotenoids
Carotenoids containing lycopenes have been shown to inhibit the growth of human prostate cancer cells in tissue cultures (cells grown in the laboratory). The primary source of lycopenes is processed tomatoes in tomato juice and tomato paste.
- fat
- obesity
Obesity may not raise the risk of prostate cancer, but it has been linked with a higher risk of getting a more aggressive type of prostate cancer. - environmental exposures
Some studies show an increased chance for prostate cancer in men who are farmers, or those exposed to the metal cadmium while making batteries, welding, or electroplating. Additional research is needed in this area to confirm whether this is a true association. - having a vasectomy, BPH (benign prostatic hyperplasia), or STD (sexually transmitted disease)
Researchers have looked at whether men who have had a vasectomy, BPH, or those who have been exposed to a sexually transmitted disease are at increased risk for prostate cancer. Some studies suggest a link, while others do not support these claims. - family history
Having a father or brother with prostate cancer more than doubles a man's risk of developing this disease. The risk is even higher for men with several affected relatives, particularly if the relatives were young at the time of diagnosis. Geneticists divide families into three groups, depending upon the number of men with prostate cancer and their ages of onset, including the following:- sporadic - sporadic means ‘occurs by chance’; such as a family with prostate cancer present in one man, at a typical age of onset.
- familial - a family with prostate cancer present in more than one person, but with no definitive pattern of inheritance and usually an older age of onset.
- hereditary - a family with a cluster of three or more affected relatives within any nuclear family (parents and their children), a family with prostate cancer in each of three generations on either the mother or father's side, or a cluster of two relatives affected at a young age (55 or less). Five percent to 10 percent of prostate cancer cases are considered hereditary. Researchers at Stanford have made important contributions to understanding hereditary prostate cancer.
- genetic factors
Some genes, when altered or mutated, give a higher risk for uncontrolled cell growth, which, in turn, can lead to tumor development. These genes have various names, but overall are referred to as "cancer susceptibility genes." Approximately 5 percent to 10 percent of all prostate cancers are known to be attributed to an inherited DNA change, such as a cancer susceptibility gene.
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