title: An evidence-based treatment algorithm for colorectal polyp cancers: results from the Scottish Screen-detected Polyp Cancer Study (SSPoCS).
abstract: Colorectal polyp cancers present clinicians with a treatment dilemma. Decisions regarding whether to offer segmental resection or endoscopic surveillance are often taken without reference to good quality evidence. The aim of this study was to develop a treatment algorithm for patients with screen-detected polyp cancers.
  
  
  
  This national cohort study included all patients with a polyp cancer identified through the Scottish Bowel Screening Programme between 2000 and 2012. Multivariate regression analysis was used to assess the impact of clinical, endoscopic and pathological variables on the rate of adverse events (residual tumour in patients undergoing segmental resection or cancer-related death or disease recurrence in any patient). These data were used to develop a clinically relevant treatment algorithm.
  
  
  
  485 patients with polyp cancers were included. 186/485 (38%) underwent segmental resection and residual tumour was identified in 41/186 (22%). The only factor associated with an increased risk of residual tumour in the bowel wall was incomplete excision of the original polyp (OR 5.61, p=0.001), while only lymphovascular invasion was associated with an increased risk of lymph node metastases (OR 5.95, p=0.002). When patients undergoing segmental resection or endoscopic surveillance were considered together, the risk of adverse events was significantly higher in patients with incomplete excision (OR 10.23, p<0.001) or lymphovascular invasion (OR 2.65, p=0.023).
  
  
  
  A policy of surveillance is adequate for the majority of patients with screen-detected colorectal polyp cancers. Consideration of segmental resection should be reserved for those with incomplete excision or evidence of lymphovascular invasion.
authors: General Surgery Training Programme, North of Scotland Deanery, UK.
authors: C H
authors: CH
authors: Richards
authors: General Surgery Training Programme, South-East of Scotland Deanery, UK.
authors: N T
authors: NT
authors: Ventham
authors: General Surgery Training Programme, West of Scotland Deanery, UK.
authors: D
authors: D
authors: Mansouri
authors: General Surgery Training Programme, East of Scotland Deanery, UK.
authors: M
authors: M
authors: Wilson
authors: General Surgery Training Programme, North of Scotland Deanery, UK.
authors: G
authors: G
authors: Ramsay
authors: General Surgery Training Programme, North of Scotland Deanery, UK.
authors: C D
authors: CD
authors: Mackay
authors: Department of Surgery, Aberdeen Royal Infirmary, Aberdeen, UK.
authors: C N
authors: CN
authors: Parnaby
authors: General Surgery Training Programme, North of Scotland Deanery, UK.
authors: D
authors: D
authors: Smith
authors: General Surgery Training Programme, North of Scotland Deanery, UK.
authors: J
authors: J
authors: On
authors: Department of Colorectal Surgery, Western General Hospital, Edinburgh, UK.
authors: D
authors: D
authors: Speake
authors: Department of Surgery, Gilbert Bain Hospital, Lerwick, UK.
authors: G
authors: G
authors: McFarlane
authors: General Surgery Training Programme, East of Scotland Deanery, UK.
authors: Y N
authors: YN
authors: Neo
authors: General Surgery Training Programme, West of Scotland Deanery, UK.
authors: E
authors: E
authors: Aitken
authors: General Surgery Training Programme, West of Scotland Deanery, UK.
authors: C
authors: C
authors: Forrest
authors: General Surgery Training Programme, West of Scotland Deanery, UK.
authors: K
authors: K
authors: Knight
authors: General Surgery Training Programme, West of Scotland Deanery, UK.
authors: A
authors: A
authors: McKay
authors: General Surgery Training Programme, South-East of Scotland Deanery, UK.
authors: H
authors: H
authors: Nair
authors: General Surgery Training Programme, South-East of Scotland Deanery, UK.
authors: C
authors: C
authors: Mulholland
authors: Department of Surgery, Victoria Hospital, Kirkcaldy, UK.
authors: J H
authors: JH
authors: Robertson
authors: University Department of Pathology, Ninewells Hospital, Dundee, UK.
authors: F A
authors: FA
authors: Carey
authors: University Department of Surgery, Ninewells Hospital, Dundee, UK.
authors: Rjc
authors: R
authors: Steele
mesh_terms: D000368:Aged; D000465:Algorithms; D001808:Blood Vessels / Q000473:pathology; D003082:Colectomy; D003111:Colonic Polyps / Q000473:pathology* / Q000601:surgery*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D018572:Disease-Free Survival; D055088:Early Detection of Cancer; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D042601:Lymphatic Vessels / Q000473:pathology; D008297:Male; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D018365:Neoplasm, Residual; D012307:Risk Factors; D012606:Scotland; D015996:Survival Rate; D057832:Watchful Waiting
keywords: CANCER; COLORECTAL CANCER SCREENING; POLYP; SURVEILLANCE