All women are at risk for breast cancer, but some are much more at risk than others, and that’s why it’s important for every woman to understand where she is on the risk spectrum.
On average, one in eight women in the United States – or 12.9% of the female population – will develop breast cancer at some point in her life, which should be enough to convince women in this average risk group to follow the widely disseminated recommendation to have an annual screening mammogram from the age of 40.
But there is a particularly vulnerable subset of women who are at significantly higher risk of early breast cancer. Based on several risk factors, these women have more than a one in five risk – over a 20% chance – of developing breast cancer in their lifetime. Thus, the screening recommendations for this high-risk population are decidedly different and more aggressive.
To start, in addition to a regular annual mammogram, they should undergo annual breast MRI (magnetic resonance imaging) screening, which uses powerful magnets instead of radiation to take detailed cross-sectional images to help radiologists to see parts of the breast that may be difficult to see with other imaging tests. Women at higher risk may also be advised to start their annual screening at a younger age.
Comprehensive risk assessment tools are available at breast imaging centers to calculate a woman’s relative risk of developing breast cancer. The assessment can be done when a woman presents to a breast center for an annual screening mammogram. Answers to several individual and family history questions are entered into the system to calculate an estimated risk. The calculation is documented on the mammogram report, and the results can guide patients’ discussions with primary care providers about ongoing screening recommendations.
A high-risk designation may be determined by one factor or a combination of factors, including:
• A family history of breast and ovarian cancer. The risk increases if a first-degree relative – a parent, sibling, or child – is diagnosed with breast cancer, particularly if diagnosed before age 45. Cancer risk can be inherited from the maternal or paternal side of the family.
• Genetic mutations. A woman is at higher risk if she has family members with certain genetic mutations, especially BRCA1 and BRCA2 genes. People at hereditary risk for breast cancer have up to an 85% lifetime risk of developing it. If genetic testing becomes a consideration, talk to a genetic counselor, nurse, or doctor who is qualified to explain and interpret the purpose and results of these tests.
• Dense breasts. Breasts made up of more connective and glandular tissue and less fatty tissue have been linked to higher cancer risks. An imaging center can check a woman’s breast density and explain this risk.
• A high body mass index (BMI) of 25 or more. This is based on weight versus height. The higher a person’s BMI, the higher the risk of cancer.
Regardless of whether a woman is at medium or high risk, if there is a history of breast cancer in a first-degree relative (parent or sibling), a woman should begin annual screening mammograms 10 years prior to breast cancer. the age at which the first-degree relative was diagnosed (but no later than 40). For example, if a woman’s mother was diagnosed with breast cancer at age 40, the woman should begin annual screening at age 30.
Although many risk factors like family history and genetics cannot be changed, all women can actively reduce their risk of breast cancer by making dietary and lifestyle choices: not smoking, maintaining a healthy weight , staying physically active, limiting alcohol – and of course, getting regular health checkups, including yearly mammograms and whatever else your risk profile deems essential.
Caitlin Lopez, MD, is medical director of the Women’s Imaging Center and chair of radiology at Berkshire Medical Center.