title: Impact of reassessment of colonic hyperplastic polyps by expert GI pathologists.
abstract: BACKGROUND
  Recommended follow-up intervals after endoscopic removal of hyperplastic polyps (HP) and sessile serrated adenomas (SSA) differ because of assumed differences in biological behaviour. However, histopathologic differentiation is difficult, with higher SSA rates reported from specialist GI histopathologists.
  
  
  OBJECTIVE
  The objective of this study was to clarify the relevance of histologic reassessment of HP.
  
  
  METHODS
  From a prospective screening colonoscopy study relevant serrated lesions (excluding distal small HP ≤5 mm) diagnosed by private practice pathologists were reassessed by four specialized GI pathologists
  
  
  METHODS
  One thousand sixty-nine screening colonoscopies were performed in patients.
  
  
  METHODS
  In terms of main outcome measurements, there is a likelihood of changes of the HP diagnosis on reassessment, as well as interrater variability.
  
  
  RESULTS
  SSA were initially diagnosed in 7 cases (0.7%) and relevant HP in 83 (7.8%; 101 lesions). Of the latter, the chance of a change in diagnosis from HP to SSA by any of the four specialist histopathologists was higher for larger (>5 mm) and right-sided lesions (19.1 vs 1.3%, OR 18.4, p = 0.04) including a higher likelihood to change recommended follow-up intervals (32.1 vs 3.3%, p < 0.01). However, follow-up intervals were determined by concomitant adenomas in 41%. Interrater variability was also higher for these lesions (p = 0.04), with an overall kappa value of 0.48. However, this issue related to only 1.2% of the 1069 study cases.
  
  
  CONCLUSIONS
  The limitations this study are the limited case number as well as limited retrospective assessment.
  
  
  CONCLUSIONS
  Right-sided HP >5 mm had a higher chance of change in diagnosis to SSA; therefore, they should probably be treated like adenomas and be removed. However, reliable data for recommendations on follow-up intervals of HP or SSA will require follow-up studies.
authors: Department of Interdisciplinary Endoscopy, University Hospital Hamburg-Eppendorf, Martinistr 52, 20246, Hamburg, Germany.
authors: Guido
authors: G
authors: Schachschal
authors: Department of Medical Biometry and Epidemiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany.
authors: Susanne
authors: S
authors: Sehner
authors: Department of Pathology, University Hospital Hamburg-Eppendorf, Hamburg, Germany.|Institute of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland.
authors: Matthias
authors: M
authors: Choschzick
authors: Department of Pathology, University Hospital Carl Gustav Carus, Dresden, Germany.
authors: Daniela
authors: D
authors: Aust
authors: Institute of Pathology, Ludwig-Maximilian University, Munich, Germany.
authors: Lydia
authors: L
authors: Brandl
authors: Institute of Pathology, Bayreuth Hospital, Bayreuth, Germany.
authors: Michael
authors: M
authors: Vieth
authors: Department of Medical Biometry and Epidemiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany.
authors: Karl
authors: K
authors: Wegscheider
authors: Department of Pathology, University Hospital Carl Gustav Carus, Dresden, Germany.
authors: Gustavo B
authors: GB
authors: Baretton
authors: Institute of Pathology, Ludwig-Maximilian University, Munich, Germany.
authors: Thomas
authors: T
authors: Kirchner
authors: Department of Pathology, University Hospital Hamburg-Eppendorf, Hamburg, Germany.
authors: Guido
authors: G
authors: Sauter
authors: Department of Interdisciplinary Endoscopy, University Hospital Hamburg-Eppendorf, Martinistr 52, 20246, Hamburg, Germany. t.roesch@uke.de.
authors: Thomas
authors: T
authors: Rösch
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000175:diagnosis* / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006287:Health Planning Guidelines; D006801:Humans; D006965:Hyperplasia; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D000072142:Pathologists / Q000592:standards; D010338:Pathology, Clinical
keywords: Histopathological second opinion; Hyperplastic polyps; Screening colonoscopy; Serrated lesions