As a second-year genetic counseling student with Northwestern University’s Genetic Counseling Program, I have worked closely with many patients who have a personal history or family history of breast cancer. Now that we are right in the middle of Breast Cancer Awareness Month, I wanted to debunk some common misconceptions that I have heard from patients about breast cancer.
Breast cancer always runs in families
Breast cancer is common - 1 in 8 women (12%) will be diagnosed with breast cancer in their lifetime. However, a majority of breast cancers are considered sporadic, meaning there is no hereditary link to their cancer. Someone can be diagnosed with breast cancer and not have any family history of breast cancer. Only 5-10% of breast cancer is hereditary, caused by an abnormal gene that is passed down in families from parent to child.
I will definitely get breast cancer if I have a BRCA1/2 gene mutation
Not true! It can certainly feel like you will get breast cancer if you have seen multiple family members diagnosed with cancer and have a known familial BRCA 1 or BRCA2 gene mutation. The risk to develop breast cancer for those who have a BRCA1 or BRCA2 gene mutation is 40-60%. Therefore, not every woman with a gene mutation will develop breast cancer.
For people who discover they have a BRCA1 or BRCA2 gene mutation, there are various proactive measures that can be done to reduce risk. These include taking a hormonal therapy called Tamoxifen or deciding to take a surgical prevention approach which is to have bilateral prophylactic mastectomies, usually done with reconstruction.
Women with BRCA1 or BRCA2 gene mutations also carry an increased risk for ovarian cancer. There is a 20-40% lifetime risk to develop ovarian cancer, compared to 1.5% lifetime risk for the average woman. To reduce their risk, women often have ovaries and fallopian tubes removed since there is no reliable screening test for early detection of ovarian cancer.
There is nothing that will reduce my risk of breast cancer
Lifestyle and environmental factors can impact your risk for breast cancer. The following can help reduce the risk of breast cancer:
Controlling your weight
Limiting alcohol intake
Breastfeeding has a protective effect and may reduce the risk of breast cancer
Limiting dose and duration of hormone replacement therapies to less than 5 years due to an increased risk for breast cancer with long-term use.
Limiting radiation and environmental exposures
Men can’t get breast cancer
Men can get breast cancer too! However, it is much less common than women. Approximately 0.1% of men will be diagnosed with breast cancer in their lifetimes. Men are encouraged to do periodic self-exams and report any changes to their physicians.
The risk for breast cancer in men is increased if they are carriers of a BRCA1/2 gene mutation. For BRCA1 carriers the lifetime risk is 1-2% and for BRCA2 carriers is 5-10% lifetime risk.
Drinking milk will cause breast cancer
Studies show no significant associations between intake of meat or dairy products and risk of breast cancer.
Missmer, Stacey A., et al. "Meat and dairy food consumption and breast cancer: a pooled analysis of cohort studies." International journal of epidemiology 31.1 (2002): 78-85.
Haraldsdottir, Alfheidur, et al. "Dietary pattern in late life and risk of breast cancer." European Journal of Public Health 27.suppl_3 (2017).
Deodorant (antiperspirant) causes breast cancer
There is no conclusive scientific evidence to support the claim that antiperspirants cause breast cancer, either because of toxin buildup or aluminum exposure.
Dana K. Mirick, Scott Davis, David B. Thomas; Antiperspirant Use and the Risk of Breast Cancer, JNCI: Journal of the National Cancer Institute, Volume 94, Issue 20, 16 October 2002, Pages 1578–1580.
Getting a mammogram will cause breast cancer
Mammograms use radiation to take a picture, similar to an X-ray, of breast tissue. They are the current gold standard screening method for breast cancer. Mammograms require very little exposure of radiation and help save lives by finding breast cancer as early as possible. According to the National Cancer Institute, “The benefits of mammography, however, nearly always outweigh the potential harm from the radiation exposure.”
The current recommendation for women is an annual screening by mammogram beginning at age 40. You should discuss any questions or concerns you may have with your physician.