Promoting colorectal cancer (CRC) screening after multiplex genetic testing and genetic counseling.

1582Background: Cancer screening guidelines recommend that germline carriers with a pathogenic variant (PV) in a CRC susceptibility gene should undergo more frequent colonoscopy screening. We assessed the impact of genetic counseling and multiplex genetic panel testing (MGPT) on adherence to colonoscopy screening. Methods: In a prospective cohort study of 2000 patients undergoing MGPT, patients completed-self-adminstered questionnaires to document colon cancer screening within one year of testing. Patients were surveyed at 3, 6, and 12 months after genetic results disclosure. Multivariable logistic regression was used to analyze an association between MGPT result and colonoscopy after adjusting for study center, personal history of colorectal cancer and personal history of colorectal surgery. Results: 2000 patients completed MGPT and 1622 (81%) completed at least one follow-up survey. 242 (12%) tested positive for at least 1 PV in any one of 25 (or 28) genes. High risk CRC gene mutations were in PMS2 (n =...