BRCA1, familial breast-ovarian cancer susceptibility 1
What are the main symptoms of Hereditary Breast and Ovarian Cancer syndrome?
The main symptom or feature of Hereditary Breast and Ovarian Cancer syndrome is an increased risk to develop cancer. The risks are highest for female breast cancer and ovarian cancer. The chance for a woman with a BRCA1 mutation to develop breast cancer by age 70 is between 55% and 65%. The chance for a woman with a BRCA1 mutation to develop ovarian cancer by age 70 is 39%. Men also have an increased risk to develop breast cancer and prostate cancer. More specifically, men with a BRCA1 mutation have a 1.2% risk to develop breast cancer by age 70. Both men and women also have an increased risk for pancreatic cancer.
Multiple studies have been done to estimate cancer risks in men and women with BRCA1 gene mutations. Therefore risk numbers may vary somewhat and these estimates may change over time as more information is learned about BRCA1-associated cancer risks. Talk to a genetic counselor or other medical professional with expertise in HBOC to learn more about BRCA1-associated cancer risks. Genetic counselors in the United States can be found on the National Society of Genetic Counselors website. Genetic counselors in Canada can be found at the Canadian Association of Genetic Counselors website.
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Tai YC, Domchek S, Parmigiani G, et al. Breast cancer risk among male BRCA1 and BRCA2 mutation carriers. J Natl Cancer Inst. 2007;99:1811-1814.
Antoniou A, Pharoah PDP, Narod S, et al. Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case series unselected for family history: a combined analysis of 22 studies. Am J Hum Genet. 2003;72:1117-1130.