Breast Cancer Risk Factors
Risk factors for breast cancer include:
- Family history of breast cancer
- Exposure to radiation
- Hormone replacement therapy after menopause
- Onset of menstrual periods before 11 years of age
- Onset of menopause after 55 years of age
- First pregnancy after 30 years of age
- High fat diet
- BRCA1 genetic marker is positive
- BRCA2 genetic marker is positive
Breast Cancer BRCA Markers
- There are a number of genetic markers that appear to increase a woman's risk of breast cancer. The most important markers are called BRCA1 and BRCA2.
- BRCA1 and BRCA2 are gene mutations often referred to as breast cancer susceptibility genes.
- When BRCA1 and BRCA2 are positive in the setting of a strong family history of breast cancer, these genes can significantly increase a woman's risk.
- The risk of breast cancer in women with these genetic abnormalities ranges from 50-85%.
- Younger women, who have breast cancer and also have a family history of breast or ovarian cancer, are more likely to have BRCA1 or BRCA2 gene mutations.
- Overall, about 5% to 10% of all cases of breast cancer are thought to be due to an inherited susceptibility to cancer, such as a mutation in BRCA1.
Continue to Breast Cancer Symptoms
- Aiello EJ, Buist DS, White E, Seger D, Taplin SH. Rate of breast cancer diagnoses among postmenopausal women with self-reported breast symptoms. J Am Board Fam Pract. 2004 Nov-Dec;17(6):408-15. 
- Collaborative Group on Hormonal Factors in Breast Cancer: Breast cancer and hormone replacement therapy: collaborative reanalysis of data from 51 epidemiological studies of 52,705 women with breast cancer and 108,411 women without breast cancer. Collaborative Group on Hormonal Factors in Breast Cancer. Lancet 1997 Oct 11; 350(9084): 1047-59. 
- Giordano SH. A review of the diagnosis and management of male breast cancer. Oncologist. 2005 Aug;10(7):471-9.