title: Low magnification narrow band imaging by inexperienced endoscopists has a high accuracy in differentiation of colon polyp histology.
abstract: OBJECTIVE
  Several studies have shown that NBI can predict the colorectal polyp histology with moderate to high accuracy. Most of them were conducted by highly experienced endoscopists at academic centers by using high magnification colonoscopes. We evaluated the accuracy of standard definition low magnification NBI in predicting the real time histology of colorectal polyps when used by inexperienced endoscopists and whether it can meet the thresholds recently defined for discard, resect and discard strategies of diminutive polyps by ASGE.
  
  
  METHODS
  The study was a prospective observational trial and involved 430 patients who underwent colonoscopy. A total of 214 polyps were detected in 317 patients. Colonoscopies were performed by a gastroenterology attending physician and two fellows who had no experience in NBI. Standard definition low magnification colonoscopes were used. The endoscopists recorded the size, Paris classification, and location of polyps under white light and consecutively described the superficial mucosal architecture and vascular pattern based on NBI International Colorectal Endoscopic criteria.
  
  
  RESULTS
  The overall accuracy of NBI in predicting adenomatous histology was 93.4%. The negative predictive value for diagnosing adenomatous histology in diminutive rectosigmoid polyps (93.3%) and the accuracy in predicting the colonoscopy surveillance interval (92.3%) were above the threshold levels defined by ASGE.
  
  
  CONCLUSIONS
  Low magnification NBI by inexperienced endoscopists has a high accuracy in predicting in vivo colorectal polyp histology encouraging its use in routine clinical practice.
authors.affiliation: Türkiye Yüksek İhtisas Hospital, Department of Gastroenterology, Sıhhiye, 06100 Ankara, Turkey. Electronic address: koksalas@yahoo.com.
authors.forename: Aydın
authors.initials: A
authors.lastname: Seref Köksal
authors.affiliation: Türkiye Yüksek İhtisas Hospital, Department of Gastroenterology, Sıhhiye, 06100 Ankara, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Yıldız
authors.affiliation: Türkiye Yüksek İhtisas Hospital, Department of Gastroenterology, Sıhhiye, 06100 Ankara, Turkey.
authors.forename: Ismail
authors.initials: I
authors.lastname: Taşkıran
authors.affiliation: Türkiye Yüksek İhtisas Hospital, Department of Pathology, Sıhhiye, Ankara, Turkey.
authors.forename: Nesrin
authors.initials: N
authors.lastname: Turhan
authors.affiliation: Türkiye Yüksek İhtisas Hospital, Department of Gastroenterology, Sıhhiye, 06100 Ankara, Turkey.
authors.forename: Erkin
authors.initials: E
authors.lastname: Oztaş
authors.affiliation: Türkiye Yüksek İhtisas Hospital, Department of Gastroenterology, Sıhhiye, 06100 Ankara, Turkey.
authors.forename: Serkan
authors.initials: S
authors.lastname: Torun
authors.affiliation: Türkiye Yüksek İhtisas Hospital, Department of Gastroenterology, Sıhhiye, 06100 Ankara, Turkey.
authors.forename: Ertuğrul
authors.initials: E
authors.lastname: Kayaçetin
mesh_terms: D002983:Clinical Competence; D003111:Colonic Polyps / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results