These specific clinical, therapeutic and prognostic features also apply tor hereditary CRC: the assessment of MSI status and the research of the underlying mutations in MLH1, MSH2, MSH6 and PMS2 genes is now part of the diagnostic process of the Lynch syndrome, allowing early detection of CRC in asymptomatic patients who undergo an intensive surveillance program [6,21,23]. The gene discussed is MLH1; the disease is colorectal carcinoma.