Síndrome de Lynch. Cáncer de colon familiar no sindrómico

Abstract

Lynch syndrome is the most common hereditary colorectal cancer (CRC) syndrome. It accounts for 2% to 4% of all CRC cases globally. It follows an autosomal dominant inheritance pattern and is defined by the presence of a pathogenic germline variant of one of the genes that encodes for DNA repair proteins (MMR), MLH1, MSH2, MSH6, PMS2, or at the 3’ end of the EPCAM gene. This syndrome entails a greater risk of developing CRC and endometrial cancer, in addition to other tumors. Its diagnosis is based on clinical criteria that take into account the family and personal history of cancer, the detection of a deficient MMR phenotype in the tumor tissue, and a genetic study of the germline of individuals at risk of having it. Its early diagnosis allows for establishing screening strategies to try to prevent or detect the presence of tumors in early stages which, in the case of CRC, has been shown to increase survival. Nonsyndromic familial CRC includes cases that have a familial component without a well-established molecular mechanism. They may benefit from more intensive follow-up than what is established for the general population.