title: Is microsatellite instability (MSI) associated with multiplicity in early stage gastric neoplasias?
abstract: OBJECTIVE
  The aim of this study was to investigate the relationship between microsatellite instability (MSI) and clinicopathologic features including multiplicity in early stage gastric neoplasias (ESGN).
  
  
  METHODS
  From November 2004 until September 2009, 372 patients with consecutive resected gastric neoplasias were retrospectively enrolled. The gastric neoplasias were composed of 117 advanced gastric cancers (AGCs) and 255 ESGNs including 31 gastric dysplasias (including low and high grade dysplasia) and 224 early gastric cancers (EGCs).
  
  
  RESULTS
  Based on microsatellite markers, high MSI (MSI-H) was observed in 61 cases (16.4%) and low MSI (MSI-L) in 14 cases (3.8%) of 372 cases. There was a positive correlation between the presence of MSI-H and progression of gastric adenoma to gastric tumor. We compared ESGNs with microsatellite stable (MSS; 223 cases, 87.5%) and ESGNs with MSI-H (24 cases, 9.4%). The ESGNs with MSI-H were only associated with older age and female gender. There were no association with Helicobacter pylori infection, intestinal metaplasia, and distal location in contrast with EGCs with MSI-H. Furthermore, multiplicity of ESGNs was not associated with MSI status.
  
  
  CONCLUSIONS
  The clinicopatholgic features of MSI-H phenotype were different according to the progression of gastric neoplasias from ESGNs to AGCs. ESGNs with MSI-H were only associated with old age, female sex. In addition ESGNs with MSI-H were not associated with an increased risk of multifocal tumors.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Hong Jun
authors.initials: HJ
authors.lastname: Park
authors.forename: Hyun-Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Jae Woo
authors.initials: JW
authors.lastname: Kim
authors.forename: So Yeun
authors.initials: SY
authors.lastname: Park
authors.forename: Bo Ra
authors.initials: BR
authors.lastname: Kim
authors.forename: Ho Yoel
authors.initials: HY
authors.lastname: Ryu
authors.forename: Il Young
authors.initials: IY
authors.lastname: Lee
authors.forename: Yong Kwan
authors.initials: YK
authors.lastname: Lee
authors.forename: Mee Yon
authors.initials: MY
authors.lastname: Cho
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology*