Risk Factors
The major risk factors for prostate cancer are age, family history, and ethnicity.
Age
Prostate cancer occurs almost exclusively in men over age 40 and most often after age 50. Two-thirds of prostate cancers are found in men over age 65. By age 70, about 65% of men have at least microscopic evidence of prostate cancers. Fortunately, the cancer is usually very slow growing and older men with the cancer typically die of something else.
Family History and Genetic Factors
Heredity plays a role in some types of prostate cancers. Men with a family history of the disease have a higher risk of developing prostate cancer. Having one family member with prostate cancer doubles a man's own risk, and having three family members increases risk by 11-fold. A specific gene, named HPC1 (for “hereditary prostate cancer”) was the first of several genes linked to inherited types of the disease.
Scientists are researching other genetic variations that may increase prostate cancer risk.
Race and Ethnicity
African-American men have higher rates of prostate cancer than men of other races. They are also more likely to develop prostate cancer at a younger age and to have more aggressive forms of the disease. However, race alone does not fully explain this difference. Prostate cancer is more common in North America and northern Europe, and less common in Africa, Latin America, and Asia. Diet and other factors may play a role. For example, Asians who live in the United States have a higher rate of prostate cancer than those who live in Asia.
Hormones
Male hormones (androgens), particularly testosterone, may play a role in the development or aggressiveness of prostate cancer. Other types of hormones, such as the growth hormone insulin-like growth factor-1 (IGF-1), may also be associated with some types of prostate cancer.
Inflammation and Infection
Researchers are studying whether prostatitis (inflammation of the prostate gland) may be associated with increased prostate cancer risk. They are also examining the possible relationship between prostate cancer and sexually transmitted infections, such as herpes virus and human papillomavirus, but no definite association has yet been found.
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Review Date: 07/26/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine,
Harvard Medical School; Physician, Massachusetts General Hospital.
Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M.,
Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
