title: Clinicopathologic features in colorectal cancer patients with microsatellite instability.
abstract: The microsatellite instability (MSI) mutational pathway is critical to carcinogenesis in a small but significant proportion of colorectal cancers. While MSI is identified in most cancers in individuals with hereditary non-polyposis colorectal cancer, the majority of MSI tumors are found in individuals with sporadic disease. Colorectal cancers arising as a result of MSI have distinct clinicopathologic features distinguishing them from those with microsatellite stability. MSI colorectal cancers affect a larger percentage of women, are usually localized proximal to the splenic flexure, and have a higher incidence of synchronous and metachronous tumors. They are associated with a mucinous histology, tumor-infiltrating lymphocytes, a Crohn's-like inflammatory response, and a higher grade but lower stage. Overall survival is better in individuals with MSI. The benefit of chemotherapy in MSI colorectal cancers, with and without lymph node metastases, remains unclear.
authors.affiliation: Department of Surgical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
authors.forename: Chandrajit P
authors.initials: CP
authors.lastname: Raut
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Pawlik
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Rodriguez-Bigas
mesh_terms: D020137:Base Pair Mismatch / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology* / Q000628:therapy; D019175:DNA Methylation; D004260:DNA Repair / Q000235:genetics; D004358:Drug Therapy; D042822:Genomic Instability; D006801:Humans; D018895:Microsatellite Repeats / Q000235:genetics*; D009154:Mutation / Q000235:genetics*; D011379:Prognosis