A woman's risk increases more if her first degree relative's breast cancer developed before menopause or if it affected both breasts. If a woman's mother was diagnosed with breast cancer before age 60, the daughter's relative risk has been shown to be 2.0, or twice as high as a woman with no first degree relatives with breast cancer. There has been much publicity surrounding the identification of two inherited gene alterations, BRCA1 and BRCA2, which predispose women to early-onset breast cancer. Family history of breast cancer in a particular woman's family may or may not be related to an inherited gene. Some proportion of family histories of breast cancer may be related to other, possibly environmental, risk factors that the family shares, such as environmental exposures where they live, or eating a common diet.
Lifestyles can be 'inherited,' too.
None of these possible environmental risk factors for breast cancer are considered 'established' at this point. Subsequent articles will provide The Ribbon readers with further background on environmental risk factors, and present a range of opportunities for risk reduction. Cornell University . We subscribe to the HONcode principles. Verify here .