title: Clinical implications of mucinous components correlated with microsatellite instability in patients with colorectal cancer.
abstract: OBJECTIVE
  Colorectal cancer (CRC) with microsatellite instability (MSI) is characterized by frequent poor differentiation or mucinous histology. The purpose of this study was to evaluate the association of MSI with clinicopathological features and the oncological outcome in patients with a mucinous component.
  
  
  METHODS
  CRC tissue samples were analysed for histology and MSI. Patients were grouped according to the mucinous content of the tumour, as follows: > 50%, mucinous adenocarcinoma (MA); ≤ 50%, adenocarcinoma with mucinous component (AMC); none, nonmucinous adenocarcinoma (NMA). Clinicopathological parameters and survival were compared between patient groups.
  
  
  RESULTS
  Of 2025 patients, 84 (4%) had MA and 124 (6%) had AMC. In addition, 202 (10%) had MSI. Patients with MA and AMC tended to have a younger age of onset, right-colon predilection, large-sized tumour and high frequency of MSI compared with those with NMA (P < 0.001). MA and AMC patients with MSI showed a trend towards right-colon predilection and infrequent lymph-node metastasis compared with those with microsatellite stability (MSS; P = 0.005-0.03). There were no survival differences between the three groups, but patients with MSI-MA demonstrated lower 4-year recurrence and better overall survival rates than those with MSS-MA (P = 0.018 and P = 0.046, respectively).
  
  
  CONCLUSIONS
  Clinicopathological features of AMC and MA were similar and closely associated with MSI status. Although the prognoses of AMC and MA were no different from that of NMA, survival of patients with an MSI-MA tumour was significantly better than for those with MSS-MA tumours.
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Y S
authors.initials: YS
authors.lastname: Yoon
authors.affiliation: Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: J
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: S-M
authors.initials: SM
authors.lastname: Hong
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: J L
authors.initials: JL
authors.lastname: Lee
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: C W
authors.initials: CW
authors.lastname: Kim
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: I J
authors.initials: IJ
authors.lastname: Park
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: S-B
authors.initials: SB
authors.lastname: Lim
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: C S
authors.initials: CS
authors.lastname: Yu
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: J C
authors.initials: JC
authors.lastname: Kim
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000235:genetics* / Q000401:mortality / Q000556:secondary*; D017668:Age of Onset; D044682:Colon, Ascending; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000473:pathology; D012189:Retrospective Studies; D015996:Survival Rate; D047368:Tumor Burden
keywords: Colorectal adenocarcinomas; adenocarcinoma; microsatellite instability; mucinous; prognosis