title: Spectrum of histopathological changes encountered in stented colorectal carcinomas.
abstract: OBJECTIVE
  Self-expanding metallic stents (SEMS) are increasingly being used in obstructing colorectal cancer (CRC) as a 'bridge to surgery', allowing conversion of potentially high-risk emergency resections to elective procedures. Stenting may cause a wide array of histological changes. We present the largest series to date of stented CRC, performed and reported at a single institution.
  
  
  RESULTS
  Stented CRC specimens received in January 2006 to December 2011 were identified from our pathology database. Slides for each case were independently reviewed by two pathologists, and a consensus was reached. A total of 72 CRCs were identified, 15 at or proximal to the splenic flexure, and 57 left-sided. Thirty-six were stage pT3 and 36 were stage pT4. Perforation was observed in 14 cases. The effects of stenting on the tumour included tumour necrosis (100%) and flat ulceration (77.8%). The spectrum of changes in the background bowel included mimics of inflammatory bowel disease, tumour regression post-neoadjuvant therapy, and ischaemia.
  
  
  CONCLUSIONS
  Given the inclusion of stenting of CRC as a bridge to surgery in the current NICE guidelines, we expect to see increasing numbers of such cases. In our study, a range of changes were encountered that mimic other bowel diseases, from simple fissuring to chronic inflammatory bowel disease and neoadjuvant regression change.
authors.affiliation: Department of Cellular Pathology, John Radcliffe Hospital, Oxford, UK.
authors.forename: Eve
authors.initials: E
authors.lastname: Fryer
authors.forename: Kim J
authors.initials: KJ
authors.lastname: Gorissen
authors.forename: Lai Mun
authors.initials: LM
authors.lastname: Wang
authors.forename: Richard
authors.initials: R
authors.lastname: Guy
authors.forename: Runjan
authors.initials: R
authors.lastname: Chetty
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000473:pathology* / Q000601:surgery*; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009336:Necrosis / Q000473:pathology; D009367:Neoplasm Staging; D015607:Stents; D016896:Treatment Outcome
keywords: colorectal carcinoma; histopathology; stent