Updated cancer risks in lynch syndrome.

Lynch syndrome, one of the most common hereditary cancer predisposition syndromes, is caused by pathogenic variants in the mismatch repair genes (MLH1, MSH2, MSH6, PMS2) and the EPCAM gene. Individuals who inherit pathogenic variants in Lynch-associated genes experience increased lifetime risk of colorectal, endometrial, and several other cancer types. Risks of Lynch-associated cancers vary by the affected gene and within each gene, especially for lower penetrance genes. This poses challenges for clinicians to provide patients and families with accurate cancer risk estimates and determine individualized surveillance protocols. Compounding this challenge is that study designs and potential biases could yield different risk estimates. In this review, we present up-to-date Lynch syndrome cancer risk estimates and discuss how study design could impact these risk estimates.