There is so much discussion in the media about annual mammograms. Mammography is the best way to ensure early breast cancer detection. The American College of Radiology (ACR), Society of Breast Imaging (SBI), and the Brem Foundation recommend annual screening mammography for all women without other risk factors at age 40. But, for some women, screening breast MRI is critical to finding early, curable breast cancers. This powerful and life-saving screening tool can save your life. But to get it, you must know your family and breast health histories.
When you get your mammogram your doctor will ask you to fill out a patient history form. The purpose of this form is to screen for breast cancer risk factors, such as: a strong family history of breast cancer, or a history of breast biopsy with atypical cells (atypia). Filling out this information every year may seem tedious and unnecessary. It is not. An accurate and up-to-date patient history is immensely important for your doctor to make individualized recommendations for you based on your risk factors.
All women with an estimated lifetime risk of breast cancer of over 20-25% should have screening breast MRI. To know whether including screening breast MRI in your individualized breast cancer screening regime, you must get an accurate calculation of your estimated lifetime risk.
There are different ways to calculate your lifetime risk of getting breast cancer. The three most common models for calculating lifetime breast cancer risk are the Claus model, the Gail model, and the Tyrer-Cuzick model (TC). It is important to remember that these models are helpful but no model is perfect.
The Claus model considers your family history of breast cancer, including first and second-degree relatives. By comparison the Gail model only looks at first-degree relatives. The Tyrer-Cuzick (TC) model, by far the most accurate,* takes into account family history, prior breast biopsy history (especially biopsy showing atypia), and estimated lifetime estrogen exposure (higher levels of prolonged estrogen exposure are associated with more lifetime risk of breast cancer).
At my radiology practice in Western New York, we screen all breast patients for breast cancer risk factors and calculate their estimated lifetime risk of breast cancer using the TC model. Here are some examples of patients who have benefitted from this approach.
Patient A: a 44-year-old female with menarche (first menstrual period) at age 12 and first childbirth at age 28. Patient A’s estimated lifetime risk of breast cancer is 11%, similar to the population risk. The recommendation for Patient A would be to continue annual screening mammograms and consider annual screening breast ultrasound if she has dense breast tissue.
If a similar woman, let’s call her Patient B, has a positive family history of breast cancer in her mother at age 60 and paternal grandmother at age 78, this woman’s estimated lifetime risk of breast cancer would be 29%. Per the ACS guidelines, the recommendation for Patient B would be an annual screening breast MRI in addition to annual screening mammography.
It is important to know that some mathematical models will give a relatively high estimated lifetime risk of breast cancer in women with history of atypia. For example, if we look at Patient C, similar to Patient A, but with a history of breast biopsy with atypia. Her estimated lifetime risk of breast cancer by TC is 42% (24% by the Gail model, and incalculable by Claus, which only looks at family history).
The American Cancer Society (ACS) does not make recommendations for or against screening atypia-only patients (i.e. patients with atypia but no family history of breast cancer) with breast MRI. It is important for atypia-only patients to discuss with their doctor the risks and benefits of considering screening breast MRI while they continue annual screening mammograms. These patients should also consider annual screening breast ultrasound if they have dense breasts.
Knowing your family history and breast health history, and sharing this information with your doctor, could save your life. I encourage you to advocate for yourself so that you get the lifesaving, individualized screening that you need and deserve.
To estimate your likelihood of developing breast cancer, specifically within 10 years of your current age, use this tool: http://www.ems-trials.org/riskevaluator/
Dr. Marie Quinn is the first of the Brem Foundation's guest bloggers. Dr. Quinn completed her Brem Breast-Imaging Fellowship in 2014. She currently practices as a Breast and Women's Imaging Specialist in Buffalo, NY where she resides with her husband and their two children. In her free time she enjoys spending time with her family, cooking, reading, practicing yoga, and renovating her home.