Updates in Genetic Testing Guidelines for Breast Cancer Susceptibility Genes: a Change in the Paradigm

Purpose of Review Up to 10% of all breast cancers are associated with inherited germline mutations. Genetic testing guidelines for hereditary breast cancer susceptibility have changed significantly since their inception in the late 1990s. The purpose of this review is to discuss the changes in technology that have improved our ability to efficiently detect germline mutations, introduce the recent paradigm change towards population-based testing currently supported by the American Society of Breast Surgeons, and highlight the challenges that expansion of testing parameters presents. Recent Findings Next-generation sequencing with multi-gene panels has replaced the traditional Sanger method of genetic testing and has quickly become the standard of care for germline mutation analysis. Benefits of this technology include increased efficiency and cost reduction. While National Comprehensive Cancer Network and US Preventive Task Force guidelines maintain family history as the basis for testing in both unaffected and affected women, new evidence supports testing of all newly diagnosed breast cancer patients and thereby cascade testing to increase rate of mutation detection prior to the diagnosis of breast cancer. Furthermore, recent studies of population-based testing in high-risk groups suggest that population-based screening in the general population is feasible and cost effective. Recent developments in technology and germline mutation testing studies support the expansion of genetic testing criteria for hereditary breast cancer. Consensus guidelines are starting to reflect these changes at a national level. The next great challenge will be determining the effectiveness of population-based testing for all women in an effort to increase breast cancer prevention for all.