Abstract
Lynch syndrome has classically been defined by several predominant malignancies. Initial
clinical criteria for diagnosis of Lynch syndrome would miss 40% of affected individuals.
As time has passed, our understanding of Lynch syndrome has evolved and will continue
to do so. The number of cancer types that are included in the Lynch phenotype is growing.
This has allowed clinicians to redefine Lynch syndrome, at risk populations, screening
needs, and diagnostic criteria. Inclusion of extracolonic malignancies and alternative
genetic pathways gives new insight into the true prevalence and penetrance of Lynch
syndrome.
Keywords
Lynch syndrome - extracolonic malignancies - mismatch repair genes - atypical phenotype