Eligibility Criteria and Genetic Testing Results from a High-Risk Cohort for Hereditary Breast and Ovarian Cancer Syndrome in Southeastern Ontario.

Germline mutations in breast and ovarian cancer are rare, with approximately 5% to 10% and 13% being hereditary in origin, respectively. In 2001, the Ontario Ministry of Health and Long Term Care, in an effort to contain costs, defined criteria to determine an individual's eligibility for BRCA genetic screening. We studied a cohort of individuals that have undergone genetic testing at Kingston General Hospital between 2001 and late 2013. We focused on determining whether the 13 risk criteria, defined by an expert working group for the Ontario Ministry of Health and Long Term Care, have performed according to expectations in this cohort. Our findings show that all of the criteria perform well by identifying carriers at the expected 10% rate defined by the guidelines. We demonstrate that loose application of the risk criteria does not further enrich for BRCA variant carriers. Our assessment of the established risk criteria that have been in use in Ontario for more than a decade, provide evidence for their effectiveness, and offer insights into how they may be expanded or improved.