title: High microsatellite instability predicts good prognosis in intestinal-type gastric cancers.
abstract: OBJECTIVE
  A subset of gastric cancers showed high microsatellite instability (MSI-H). The reported clinicopathological features of MSI-H gastric cancers are heterogeneous, and specific factors associated with prognosis have not been identified.
  
  
  METHODS
  We analyzed the clinicopathological characteristics and prognostic factors in a large series (161 cases) of MSI-H gastric cancers, and compared the results to 315 cases of microsatellite-stable or low microsatellite-instable gastric cancers.
  
  
  RESULTS
  The frequency of MSI-H gastric cancers was 9% (161/1786). MSI-H gastric cancers have distinct clinicopathological features, including female sex, older age, antral location, well-to-moderate differentiation, intestinal-type Lauren classification, expanding-type Ming classification, a non-signet-ring cell component, the presence of a mucinous component, a moderate-to-severe lymphoid stromal reaction, and a lower tumor stage. The MSI-H phenotype was associated with better prognosis (P = 0.044), and male sex (P = 0.035, hazard ratios [HR]: 0.23), intestinal-/mixed-type Lauren classification (P < 0.001, HR: 0.09) and lower tumor stages (1 and 2, P = 0.001, HR: 0.08) were independently-favorable prognostic factors.
  
  
  CONCLUSIONS
  With unique clinicopathological features, intestinal-type MSI-H gastric cancers are associated with good prognosis and can be classified as a different subset of gastric cancers.
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyunki
authors.initials: H
authors.lastname: Kim
authors.forename: Ji Yeong
authors.initials: JY
authors.lastname: An
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Noh
authors.forename: Sung Kwan
authors.initials: SK
authors.lastname: Shin
authors.forename: Yong Chan
authors.initials: YC
authors.lastname: Lee
authors.forename: Hoguen
authors.initials: H
authors.lastname: Kim
mesh_terms: D000368:Aged; D016009:Chi-Square Distribution; D005260:Female; D005743:Gastrectomy; D020022:Genetic Predisposition to Disease; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008197:Lymph Node Excision; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D009367:Neoplasm Staging; D010641:Phenotype; D016016:Proportional Hazards Models; D056910:Republic of Korea; D018570:Risk Assessment; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000145:classification / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D016896:Treatment Outcome