Clinical and pathological characteristics of sporadic colorectal carcinomas with DNA replication errors in microsatellite sequences

摘要: DNA replication errors (RERs) in repeated nucleotide sequences due to defective mismatch repair genes have been reported a subset of sporadic colorectal carcinomas and the majority tumors from patients with hereditary nonpolyposis cancer syndrome (HNPCC). We detected RER 18 cases (13%) prospective series 137 stage II III (Dukes' B C) carcinomas. The clinical pathological features RER-positive differed those without RER. cancers tended be somewhat younger (60 +/- 5 years, range 22-83, versus 66 1, 27-90, P = 0.2 unequal variances) had marked preponderance proximal splenic flexure (17/18, 94%, 41/119, 34%, < 0.0001). Only two (11%) family history cancer. In comparison 41 RER-negative colonic cancers, more frequent exophytic growth (P 0.04), large size 0.03), poor differentiation 0.0004), extracellular mucin production 0.003) Crohn's-like lymphoid reaction 0.003), trend toward less p53 gene product overexpression by immunohistochemistry (3/17, 18%, 18/41, 44%, 0.06). conclude that has unique biological may indicate inherited germline mutation, de novo or somatic mutations involved HNPCC.