Grant: Project Grant

The Ontario Breast Screening Program (OBSP) High-Risk Screening Program includes women between the ages of 30 and 69 years who have a very high risk of breast cancer. As part of this program, women undergo breast screening every year with both magnetic resonance imaging (MRI) and mammogram. Because of their very high risk, these women are also frequently considered for preventive surgeries (e.g., having their breasts and/or ovaries removed). While potentially reducing a woman's risk of breast cancer, these surgeries can seriously impact their quality of life. New markers of breast cancer risk that can identify the women who would benefit the most from these interventions are needed. This will help provide personalized recommendations for both breast cancer prevention and screening. Mammograms generate an image of the breast where fat appears white and breast tissue appears dark. The amount of breast tissue a woman has is called mammographic density (MD). Having high MD is known to strongly increase a woman's risk of breast cancer. This relationship is well known in average-risk women but it is not known if it is also true for high-risk women. Another characteristic of the breast that might tell us about a woman's risk of breast cancer is seen on MRI and is called background parenchymal enhancement (BPE). Small studies have shown that having high BPE may increase a woman's risk of getting breast cancer. Dr. Brooks and her research team will examine the relationship between MD and BPE and risk of breast cancer in women being screened in the OBSP High-Risk Program. This study will be the first to look at the relationship between BPE in an established screening program. This study will provide us with information that will better determine a woman's risk of getting breast cancer, helping to guide recommendations for breast cancer screening and preventive interventions. This could significantly impact how high-risk women are screened and treated in the future.