Prevalence of Lynch syndrome and Lynch-like syndrome among patients with colorectal cancer in a Japanese hospital-based population.

摘要: Objective We investigated the prevalence of Lynch syndrome and Lynch-like among Japanese colorectal cancer patients, as there have been no credible data from Japan. Methods Immunohistochemical analyses for mismatch repair proteins (MLH1, MSH2, MSH6 PMS2) were carried out in surgically resected, formalin-fixed paraffin-embedded specimens obtained 1,234 newly diagnosed patients between March 2005 April 2014. The presence/absence BRAF V600E mutation hypermethylation MLH1 promoter was analyzed where necessary. Genetic testing finally undertaken suspected having syndrome. Results By universal screening approach with immunohistochemical analysis followed by methylation status, 11 (0.9%) identified candidates genetic testing. Out 9 (0.7%) syndrome; responsible genes included (n = 1), MSH2 4), EPCAM 1) 3). remaining two (0.2%) regarded syndrome, since biallelic somatic deletion relevant detected absence germline alterations. None cases epimutation. Conclusions all Japan is same range that recently reported studies Western population. seems to be extremely low.