title: Metachronous carcinomas in colorectum and its clinicopathological significance.
abstract: OBJECTIVE
  The study was designed to examine the significance of colorectal metachronous carcinoma in a large cohort of patients.
  
  
  METHODS
  Over a mean follow-up period of 10 years, the clinicopathological features, microsatellite instability (MSI) and clinical follow-up of 56 patients with metachronous colorectal carcinoma were analysed.
  
  
  RESULTS
  The prevalence of metachronous colorectal carcinoma was 2.1 %. The metachronous colorectal carcinomas appeared between 7 and 246 months (mean = 66 months) after surgical resection of the index colorectal carcinomas. Thirty-six per cent (n = 20) of the metachronous carcinoma occurred more than 5 years after the operation of the index carcinoma. Of the 56 patients, 20 % (n = 11) of the metachronous colorectal carcinomas were mucinous adenocarcinoma. Cancers detected in the secondary operations (metachronous colorectal carcinomas), when compared with the primary index cancers, were smaller, showed higher proportions of mucinous adenocarcinoma and more often located in the proximal colon. Patients with metachronous colorectal cancers had higher prevalence of mucinous adenocarcinoma, loss of staining for MSI markers and better survival rates than other patients with colorectal cancers.
  
  
  CONCLUSIONS
  Patients with metachronous colorectal carcinomas have characteristic features, and attention to these features is important for better management of this group of cancer.
authors: Cancer Molecular Pathology, School of Medicine and Griffith Health Institute, Griffith University, Gold Coast, QLD 4222, Australia. a.lam@griffith.edu.au
authors: Alfred King-Yin
authors: AK
authors: Lam
authors: Vinod
authors: V
authors: Gopalan
authors: Robert
authors: R
authors: Carmichael
authors: Petra Gertraud
authors: PG
authors: Buettner
authors: Melissa
authors: M
authors: Leung
authors: Robert
authors: R
authors: Smith
authors: Cu-Tai
authors: CT
authors: Lu
authors: Yik-Hong
authors: YH
authors: Ho
authors: Simon
authors: S
authors: Siu
mesh_terms: D000328:Adult; D000368:Aged; D015179:Colorectal Neoplasms / Q000235:genetics / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000473:pathology*; D016019:Survival Analysis