Researchers believe that ovarian cancer is caused by a combination of genetic and nongenetic factors. In addition to older age, doctors believe there are a number of genetic and environmental factors increase a woman's risk for developing ovarian cancer.
When considering your personal risk for ovarian cancer, it is important to keep in mind that risk factors are not absolute: you can have risk factors and never develop ovarian cancer. Alternatively, some people who do not have any risk factors still develop the disease.
Genetic Factors
Genes play a role in every aspect of our body and its development, from defining visible traits such as skin and eye color, to influencing the development of cancer.
Scientists believe that approximately 10 percent of ovarian epithelial cancer can be attributed to inherited alterations, or mutations, in the BRCA1 and BRCA2 genes. In women with Ashkenazi Jewish ancestry, however, that rate is believed to be as high as 40 percent, as a result of their genetic heritage.
Mutations in these two genes also confer an increased risk of other cancers, primarily breast cancer. The genetic cancer syndrome called HNPCC (hereditary nonpolyposis colorectal cancer), also increases a woman's risk of developing ovarian cancer, although less than 2 percent of ovarian cancers are thought to be attributed to the syndrome. HNPCC is also characterized by an increased risk for colon, endometrial, and stomach cancer.
Nongenetic Factors
Other factors may increase your risk for ovarian cancer. These include:
- a high-fat diet
- early-onset menses (first menstrual period at an early age)
- never having used birth control pills
- never having given birth to a child
- never having breast-fed a child
References:
Baker, T. R. and M. S. Piver. 1994. Etiology, biology, and epidemiology of ovarian cancer. Semin Surg Oncol 10(4): 242-8.
Cannistra, S. A. 2004. Cancer of the ovary. N Engl J Med. 351:2519-2529.
Daly, M. and G. I. Obrams. 1998. Epidemiology and risk assessment for ovarian cancer. Semin Oncol 25(3): 255-64.
Data, A. C. S. 2004. Data from the American Cancer Society website. www.cancer.org
Fitch, M. I., R. E. Gray, et al. 1999. Gynecologists' perspectives regarding ovarian cancer. Cancer Prev Control 3(1): 68-76.
Gayther, S. A., J. Mangion, et al. 1997. Variation of risks of breast and ovarian cancer associated with different germline mutations of the BRCA2 gene. Nat Genet 15(1): 103-5.
Ozools, R. F. et al. 1997. Epithelial Ovarian Cancer. Philadelphia, Lippincott-Raven.
Stratton, J. F., S. A. Gayther, et al. 1997. Contribution of BRCA1 mutations to ovarian cancer. N Engl J Med 336(16): 1125-30.
