Patients with clinical criteria for Lynch syndrome with and without mutations in DNA repair genes (MLH1 and MSH2). A challenge for the clinician

BACKGROUND AND OBJECTIVES: The objective was to study the clinicopathologic characteristics of patients diagnosed of colorectal cancer (CRC) with clinical criteria for Lynch syndrome, in our region, in order to assess and improve the care of them and their families in the Genetic Counseling Unit of our hospital. PATIENTS AND METHODS: This was an observational, transversal retrospective study. The studied sample was made up of all the patients with clinical criteria for Lynch syndrome, who underwent a molecular analysis test in the Genetic Counseling Unit of Salamanca, during the period 2004-2009. We included patient and tumor related variables and the presence or absence of mutations in MLH1 and MSH2. RESULTS: A total of 76 patients were included in the analysis. Fifteen of them carried a mutation either in MLH1 or in MSH2. The mean age at diagnosis of colorectal cancer was 51.2 and 54.3 years in the group with and without mutation respectively, with a similar gender distribution in both groups. A wide phenotypic heterogeneity was found in the sample. CONCLUSIONS: Lynch syndrome is an entity difficult to categorize from a clinical point of view. Therefore, it is important to be alert for a better management of these patients and their families.