The More You Know: Taking Control of Your Health
Written By: Scott Weissman, MS, CGC, Certified Genetic Counselor
October is Breast Cancer Awareness Month and a reminder to take a few minutes to better understand if your risk of developing breast cancer is higher than average. Knowing this information will allow your healthcare professionals to determine whether you:
- Need early and increased breast cancer screening with both mammogram and MRI of the breast
- Are a candidate to take medication to reduce your breast cancer risk
- Should be referred to a genetic counselor or other genetics professional to discuss genetic testing.
About 1 in 8 women will develop breast cancer, which equates to a 12% chance of developing breast cancer over the course of a woman’s life. However, not all women face the same level of risk as there are factors known to increase a woman’s risk; these include:
- Early age at first menstrual period (less than age 11y)
- Birth of a first child after age 35
- Menopause on setting a later age (greater than age 55y)
- History of a biopsy of the breast, or abnormality found on the biopsy (atypical cells or lobular carcinoma in situ)
- Dense breast tissue identified on mammogram
- Family history of breast cancer in women or men or ovarian cancer
- Mutation in a hereditary breast cancer gene (e.g., BRCA1, BRCA2, PALB2, CHEK2)
- Elevated body mass index (BMI)
If you have one or more of the above listed risk factors, your risk of breast cancer may be elevated and warrants bringing this up with your healthcare professional. Your doctor can refer you to a genetic counselor or other provider who can perform a formal cancer risk assessment. During a cancer risk assessment, a genetic counselor will ask you about your personal medical history and will map out a complete family history to see who in your family had cancer. From this information, the genetic counselor can run computer models that quantify your risk of developing breast cancer. The American Cancer Society and National Comprehensive Cancer Network, two organizations that create cancer screening and treatment guidelines, both recommend increased breast cancer screening with yearly mammogram and breast MRI, as well as more frequent clinical breast exams by a healthcare professional for women who have a lifetime risk of breast cancer that is greater than 20-25%, or about double the average breast cancer risk. Additionally, a genetic counselor can help determine whether you are a candidate to take a medication called tamoxifen or raloxifene (Novladex or Evista). These medications, if used for at least 5 years, reduce a woman’s chance of developing breast cancer by at least 50%. If you are a candidate, typically the genetic counselor would refer you to a medical oncologist to have a more complete discussion of the pros and cons of taking a medication for breast cancer prevention, termed chemoprevention.
The genetic counselor or other genetics professional could also assess whether you or someone in your family is a candidate for genetic testing. Genetic testing can help identify whether you face a very high risk (approximately 40% or higher) of breast cancer that would warrant discussions of taking a more preventative approach with the breast cancer risk. In addition to chemoprevention, a woman may choose to have her breasts preventatively removed (risk-reducing bilateral mastectomy) so that she significantly lowers the likelihood of getting breast cancer. This is something that not all women choose to do, but a genetic counselor can walk someone through the decision-making process to see if this a procedure that makes sense for the individual.
Genetic testing can determine whether a woman faces an increased risk of other cancers (e.g., ovarian or uterine cancer) and whether any other increased cancer screening or prevention is worth discussing. The genetic information can also benefit her other family members, men and women both, as many of the genes that cause breast cancer can increase the risk of cancer in men (prostate, breast, pancreas, colon). In addition, current guidelines recommend genetic testing for any Ashkenazi Jewish woman who has had breast cancer regardless of her age of onset or family history.
Since mutations in the BRCA1 and BRCA2 genes are more common in Ashkenazi Jewish women and men (about 1 in 40 carrier a BRCA1/2 mutation), many people of Ashkenazi Jewish ancestry have undergone BRCA1/2 genetic testing. A study published earlier this year by Dr. Mary Claire King’s (discoverer of the BRCA1 gene) research group found that among Ashkenazi Jewish women who had breast cancer, underwent genetic testing and tested positive for a hereditary breast cancer gene, approximately 78% had mutations in BRCA1/2, but another approximately 22% had mutations in other breast cancer causing genes. The study’s conclusion suggests that all Ashkenazi Jewish women should be tested for all breast cancer genes. Therefore, if you underwent genetic testing and were not found to have a mutation in the BRCA1 or BRCA2 or you have never had genetic testing, it may be time to consider having additional genetic testing performed.
By investigating your personal and family history risk factors, you can learn more about what your chance is of developing breast cancer. This will better arm you to develop an individualized cancer screening regimen to, ideally, detect cancer at its earliest stage if it develops or take additional steps to minimize the chance of breast cancer ever occurring. Speak to your family members about whether you have a family history of breast or other cancers and if you do, and you have any of the other risk factors listed above, speak to your healthcare provider and ask for a referral to see a genetic counselor or other genetics professional. I may be reached directly with additional questions (info@chicagogenetics.com).
Get informed, empower yourself and take control.
As founder of Chicago Genetic Consultants, LLC, Scott M. Weissman is bringing the science of genetics and genetic testing directly to individuals and families. With over 15 years of experience, Scott understands all aspects of the genetic counseling and testing journey from the decision to seek advice, the pros and cons of genetic testing, how genetic information can impact an individual and their family, and issues related to insurance coverage, privacy and discrimination concerns. His primary focus is hereditary cancer syndromes but also works with individuals who have hereditary cardiac disease, neurologic conditions as well as a multitude of other adult onset genetic conditions and the burgeoning area of pharmacogenomics.
Follow Chicago Genetic Consultants on Twitter @chicagogenetics.