title: Diagnostic accuracy of magnification endoscopy with acetic acid enhancement and narrow-band imaging in gastric mucosal neoplasms.
abstract: OBJECTIVE
  Magnification endoscopy with narrow-band imaging (NBIME) and NBIME with acetic acid enhancement (A-NBIME) visualize the capillary and microstructure patterns of the gastric mucosal surface, respectively. This study aimed to compare the diagnostic accuracy and interobserver agreement for white-light endoscopy (WLE), NBIME, and A-NBIME in the different histologic types of gastric mucosal neoplasm.
  
  
  METHODS
  Consecutive gastric neoplasms (n = 220; 49 adenomas, 144 differentiated adenocarcinomas, and 27 undifferentiated adenocarcinomas) were photographed with WLE, NBIME, and A-NBIME. Macroscopic patterns using WLE, capillary patterns using NBIME, and microstructure patterns using A-NBIME were respectively classified into type M1/M2/M3, type C1/C2/C3/C4, and type S1/S2/S3, as the indicators of adenoma, differentiated adenocarcinoma, and undifferentiated adenocarcinoma (Type C4, unevaluable because of capillary invisibility), according to the previously reported classifications. Endoscopic images were independently reviewed by three experts and three non-experts. Diagnostic accuracy and interobserver diagnostic agreement were compared among the modalities.
  
  
  RESULTS
  Kappa values (95 % confidence interval [CI]) for WLE, NBIME, and A-NBIME diagnosis were 0.36 (0.33 - 0.39), 0.58 (0.54 - 0.61), and 0.62 (0.55 - 0.68) for experts and 0.31 (0.29 - 0.33), 0.36 (0.34 - 0.38), and 0.52 (0.48 - 0.56) for non-experts, showing good reproducibility of A-NBIME diagnosis regardless of proficiency. All experts and non-experts diagnosed the histologic types statistically more accurately with A-NBIME than with WLE and NBIME (P < 0.05). Overall the "experts-agreed" diagnostic accuracy (95 %CI) was 75.5 % (70.0 - 81.0) for WLE vs. 74.1 % (67.6 - 80.6) for NBIME vs. 90.5 % (86.7 - 94.1) for A-NBIME (P < 0.05). WLE and NBIME were insufficient to predict the diagnosis of adenomas and undifferentiated adenocarcinomas.
  
  
  CONCLUSIONS
  A-NBIME showed statistically significantly higher diagnostic accuracy for gastric mucosal neoplasms, with good reproducibility, compared with WLE and NBIME, which provided similar lower accuracy.
authors.affiliation: Department of Gastroenterology, Tottori Municipal Hospital, Tottori, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Shibagaki
authors.affiliation: Division of Endoscopy, Kaken Hospital, International University of Health and Welfare, Ichikawa, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Amano
authors.affiliation: Department of Gastroenterology, Faculty of Medicine, Shimane University, Izumo, Japan.
authors.forename: Norihisa
authors.initials: N
authors.lastname: Ishimura
authors.affiliation: Department of Gastroenterology, Tottori Municipal Hospital, Tottori, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Taniguchi
authors.affiliation: Department of Gastroenterology, Tottori Municipal Hospital, Tottori, Japan.
authors.forename: Hiraku
authors.initials: H
authors.lastname: Fujita
authors.affiliation: Department of General Internal Medicine, Tottori Municipal Hospital, Tottori, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Adachi
authors.affiliation: Department of General Internal Medicine, Tottori Municipal Hospital, Tottori, Japan.
authors.forename: Eichi
authors.initials: E
authors.lastname: Kakehi
authors.affiliation: Department of General Internal Medicine, Tottori Municipal Hospital, Tottori, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Fujita
authors.affiliation: Department of Pathology, Tottori Municipal Hospital, Tottori, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Department of Gastroenterology, Faculty of Medicine, Shimane University, Izumo, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kinoshita
mesh_terms: D019342:Acetic Acid; D000230:Adenocarcinoma / Q000473:pathology*; D000236:Adenoma / Q000473:pathology*; D003287:Contrast Media; D003430:Cross-Sectional Studies; D005753:Gastric Mucosa / Q000473:pathology; D005773:Gastroscopy / Q000379:methods*; D006801:Humans; D062048:Narrow Band Imaging / Q000379:methods*; D015588:Observer Variation; D011446:Prospective Studies; D013274:Stomach Neoplasms / Q000473:pathology*
chemical_list: D003287:Contrast Media; D019342:Acetic Acid