title: Investigating endoscopic features of sessile serrated adenomas/polyps by using narrow-band imaging with optical magnification.
abstract: BACKGROUND
  A sessile serrated adenoma/polyp (SSA/P) is a common type of colorectal polyp that possesses malignant potential. Although narrow-band imaging (NBI) can easily differentiate neoplastic lesions from hyperplastic polyps (HPs), SSA/Ps can be a challenge to distinguish from HPs.
  
  
  OBJECTIVE
  To investigate specific endoscopic features of SSA/Ps by using NBI with optical magnification.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Single high-volume referral center.
  
  
  METHODS
  A total of 289 patients with histopathologically proven SSA/Ps or HPs obtained from colonoscopic polypectomy.
  
  
  METHODS
  Endoscopic images obtained by using NBI with optical magnification of 242 lesions (124 HPs, 118 SSA/Ps) removed between January 2010 and December 2012 were independently evaluated by 2 experienced endoscopists. Three external experienced endoscopists systematically validated the diagnostic accuracies by using 40 lesions (21 HPs and 19 SSA/Ps) removed between January and March 2013.
  
  
  METHODS
  Specific endoscopic features of SSA/Ps by using 5 potential characteristics: dilated and branching vessels (DBVs), irregular dark spots, a regular network pattern, a disorganized network pattern, and a dense pattern.
  
  
  RESULTS
  Multivariate analysis demonstrated that DBV had a 2.3-fold odds ratio (95% confidence interval, 0.96-5.69) among SSA/Ps compared with HPs (sensitivity, 56%; specificity, 75%; accuracy, 65%). Interobserver and intraobserver agreement indicated almost perfect agreement for DBVs in both the evaluation and validation studies. When DBVs, proximal location, and tumor size (≥10 mm) were combined, the positive predictive value was 92% and the area under the curve was 0.783 in the receiver-operating characteristics by using the validation group.
  
  
  CONCLUSIONS
  Retrospective study.
  
  
  CONCLUSIONS
  The current study suggests that a DBV is a potentially unique endoscopic feature of a colorectal SSA/P.
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Yamada
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Sakamoto
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Otake
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: Department of Biostatistics, National Cancer Center, Tokyo, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Kuchiba
authors.affiliation: Department of Pathology and Clinical Laboratories, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Taniguchi
authors.affiliation: Molecular Pathology Division, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sekine
authors.affiliation: Department of Pathology and Clinical Laboratories, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Kushima
authors.affiliation: Department of Gastroenterology, University of Tennessee College of Medicine, Erlanger Hospital, Chattanooga, TN, USA.
authors.forename: Hemchand
authors.initials: H
authors.lastname: Ramberan
authors.affiliation: Department of Gastroenterology, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Adolfo
authors.initials: A
authors.lastname: Parra-Blanco
authors.affiliation: TF Clinic, Tokyo, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Fujii
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Matsuda
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Saito
mesh_terms: D000236:Adenoma / Q000175:diagnosis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000175:diagnosis*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D062048:Narrow Band Imaging; D015588:Observer Variation; D012189:Retrospective Studies; D012680:Sensitivity and Specificity