title: Poorly differentiated colorectal cancers: correlation of microsatellite instability with clinicopathologic features and survival.
abstract: OBJECTIVE
  To evaluate the association of microsatellite instability (MSI) with clinicopathologic features and oncologic outcomes in patients with poorly differentiated colorectal cancer (PD).
  
  
  METHODS
  Study patients were divided into well-differentiated colorectal cancer (WD) and PD, which were compared according to histologic differentiation and MSI status.
  
  
  RESULTS
  Among 1,941 patients, PD was more frequent among microsatellite-unstable tumors (23.6%) than among microsatellite-stable (MSS) tumors (4.2%, P < .001). Patients with PD had worse 4-year overall survival rates than patients with WD (78.6% vs 88.2%, P = 0.010). Compared with MSS-PD tumors, MSI-PD tumors were characterized by right-colon predilection, larger size, and infrequent lymph node metastasis (P < .001 to P = .007).
  
  
  CONCLUSIONS
  The clinicopathologic characteristics of PD were closely associated with those of MSI. The outcomes of MSI-PD tumors were better than those of MSS-PD tumors, but this finding did not reach statistical significance.
authors: Department of Surgery, University of Ulsan College of Medicine, 86, Asanbyeongwon-gil, Songpa-gu, Seoul 138-736, Korea.
authors: Haitao
authors: H
authors: Xiao
authors: Yong Sik
authors: YS
authors: Yoon
authors: Seung-Mo
authors: SM
authors: Hong
authors: Seon Ae
authors: SA
authors: Roh
authors: Dong-Hyung
authors: DH
authors: Cho
authors: Chang Sik
authors: CS
authors: Yu
authors: Jin Cheon
authors: JC
authors: Kim
mesh_terms: D000328:Adult; D000368:Aged; D002454:Cell Differentiation / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate
keywords: Colorectal adenocarcinoma; Microsatellite instability; Prognosis