Breast Cancer Treatment for Mutation Carriers

Some 1.7 million new cases of breast cancer are expected to be diagnosed worldwide in 2016, of which approximately 5% are estimated to be due to mutations in the BRCA1 and BRCA2 genes. Recent evidence shows that these BRCA-associated breast cancers should receive different, more targeted treatments compared to treatment for those with sporadic breast cancer to decrease risks of new cancers and increase chance of survival. Most notably, bilateral mastectomy has been shown to significantly reduce the risks of contralateral and ipsilateral breast cancers in women with BRCA-associated breast cancer. This translates into a survival advantage. Also, for women with breast cancer, chemotherapy may be offered based on nodal status and tumor aggressiveness. However, evidence indicates that BRCA status should also be considered and carriers might respond better to a specific group of drugs. Oophorectomy is also another optional treatment for BRCA mutation carriers that has been shown to reduce the risk of contralateral and ipsilateral breast cancer. However, to realize the benefits of this recent research, women must know their BRCA status at the time of breast cancer diagnosis when making surgical and medical decisions. Yet, due to current genetic testing criteria and the length of time that genetic testing takes in Canada, testing at the time of breast cancer diagnosis is generally not offered, and if it is, test results are not available prior to breast cancer surgery. These 2 obstacles may be leading women to elect for less personalized and targeted treatments, which very well may affect cancer-related mortality and survival rates.