Real-world outcomes of genetic testing in a GU genetics clinic and evaluation of current guidelines.

668Background: Several known hereditary cancer syndromes confer an increased risk for genitourinary (GU)-related malignancies. Various guidelines indicate when to refer patients to genetic counseling for GU cancers, but there are limited data on the performance of these guidelines in clinical practice, and the association between testing outcome and clinical and familial features that may delineate a heritable syndrome. The purpose of this study is to determine the most common indications for ordering genetic testing in a GU Genetics Clinic and evaluate the relationship between the indication for germline testing and outcome. Methods: An IRB-approved retrospective chart review was performed for 350 patients seen in a GU Genetics Clinic at a single comprehensive cancer center from 2014-2018. Subgroups of patients were formed based on their indication for genetic testing. Exact binomial tests were used to compare the proportion of patients with a positive (pathogenic or likely pathogenic) germline variant f...