title: Management of colorectal polyp cancers.
abstract: BACKGROUND
  Management of malignant colorectal polyps is controversial. The options are resection or surveillance. Resection margin status is accepted as an independent predictor of adverse outcome. However, the rate of adverse outcome in polyps with a resection margin of <1mm  has not been investigated.
  
  
  METHODS
  A retrospective search of the pathology database was undertaken. All polyp cancers were included. A single histopathologist reviewed all of the included polyp cancers. Polyps were divided into three groups: clear resection margin, involved resection  margin and unknown resection margin. Polyps were also analysed for tumour grade, morphology, Haggitt/Kikuchi level and lymphovascular invasion. Adverse outcome was defined as residual tumour at the polypectomy site and/or lymph node metastases in the surgical group and local or distant recurrence  in the surveillance group.
  
  
  RESULTS
  Sixty-five polyps (34 male patients, mean age: 73 years, range: 50-94 years) were included. Forty-six had clear polyp resection margins; none had any adverse outcomes. Sixteen patients had involved polyp resection margins and twelve of these underwent  surgery: seven had residual tumour and two of these patients had lymph node metastases. Four underwent surveillance, of whom two developed local recurrence. Three patients had resection margins on which the histopathologist was unable to comment. All patients with a clear resection margin  had no adverse outcome regardless of other predictive factors.
  
  
  CONCLUSIONS
  Polyp cancers with clear resection margins, even those with <1mm clearance, can be treated safely with surveillance in our experience. Polyp cancers with unknown or involved resection margins should be treated  surgically.
authors.affiliation: Salisbury District Hospital, Odstock Road, Salisbury, Wiltshire SP2 8BJ, UK. shehryer.naqvi02@imperial.ac.uk
authors.forename: S
authors.initials: S
authors.lastname: Naqvi
authors.forename: S
authors.initials: S
authors.lastname: Burroughs
authors.forename: H S
authors.initials: HS
authors.lastname: Chave
authors.forename: G
authors.initials: G
authors.lastname: Branagan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000473:pathology / Q000601:surgery*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000209:etiology; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome