title: Interobserver agreement in detection of "white globe appearance" and the ability of educational lectures to improve the diagnosis of gastric lesions.
abstract: BACKGROUND
  White globe appearance (WGA) refers to a small white lesion of globular shape underneath cancerous gastric epithelium that can be clearly visualized by magnifying endoscopy with narrowband imaging (M-NBI). WGA has been reported to be a novel endoscopic marker that is highly specific in differentiating early gastric cancer (GC) from low-grade adenoma, and has a significantly higher prevalence in early GCs than in noncancerous lesions. However, interobserver agreement in detecting WGA and whether training intervention can improve diagnostic accuracy are unknown.
  
  
  METHODS
  Twenty sets of M-NBI images were examined by 16 endoscopists. The endoscopists attended a lecture about WGA, and examined the images again after the lecture. Interobserver agreement in detecting WGA in the second examination and increases in the proportion of correct diagnoses and the degree of confidence of diagnoses of cancerous lesions were evaluated.
  
  
  RESULTS
  The kappa value for interobserver agreement in detecting WGA in the second examination was 0.735. The proportion of correct diagnoses was significantly higher in the second examination compared with the first examination when WGA was present (95.5% vs 55.4%; P < 0.001), but not when WGA was absent (61.6% vs 52.7%; P = 0.190). The proportion of correct diagnoses with a high degree of confidence was significantly higher in the second examination, both with WGA (91.1% vs 29.5%; P < 0.001) and without WGA (36.6% vs 20.5%; P = 0.031).
  
  
  CONCLUSIONS
  The detection of WGA by endoscopists was highly reproducible. A brief educational lecture about WGA increased the proportion of correct diagnoses and the degree of confidence of diagnoses of GC with WGA.
authors.affiliation: Department of Gastroenterology, Ishikawa Prefectural Central Hospital, 2-1 Kuratsukihigashi, Kanazawa, Ishikawa, 920-8530, Japan.|Department of Gastroenterology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Omura
authors.affiliation: Department of Gastroenterology, Ishikawa Prefectural Central Hospital, 2-1 Kuratsukihigashi, Kanazawa, Ishikawa, 920-8530, Japan.
authors.forename: Naohiro
authors.initials: N
authors.lastname: Yoshida
authors.affiliation: Department of Gastroenterology, Kanazawa Medical Center, Kanazawa, Ishikawa, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Department of Gastroenterology, Japan Community Health care Organization Kanazawa Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Miwa
authors.affiliation: Department of Gastroenterology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Takatori
authors.affiliation: Department of Gastroenterology, Kanazawa Municipal Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Tsuji
authors.affiliation: Department of Gastroenterology, Tonami General Hospital, Tonami, Toyama, Japan.
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Inamura
authors.affiliation: Department of Gastroenterology, Saiseikai Kanazawa Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Shirota
authors.affiliation: Department of Gastroenterology, Fukui Prefectural Hospital, Fukui, Fukui, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Aoyagi
authors.affiliation: Department of Gastroenterology, Hokuriku Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Takaharu
authors.initials: T
authors.lastname: Masunaga
authors.affiliation: Department of Diagnostic Pathology, Ishikawa Prefectural Central Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Katayanagi
authors.affiliation: Department of Diagnostic Pathology, Ishikawa Prefectural Central Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kurumaya
authors.affiliation: Department of Gastroenterology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Kaneko
authors.affiliation: Department of Gastroenterology, Ishikawa Prefectural Central Hospital, 2-1 Kuratsukihigashi, Kanazawa, Ishikawa, 920-8530, Japan. doyama.134@ipch.jp.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Doyama
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis*; D000236:Adenoma / Q000175:diagnosis; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D005773:Gastroscopy / Q000193:education* / Q000379:methods*; D006801:Humans; D008297:Male; D062048:Narrow Band Imaging / Q000379:methods; D015588:Observer Variation; D013274:Stomach Neoplasms / Q000175:diagnosis*
keywords: Gastric cancer; Magnifying endoscopy; Narrowband imaging; White globe appearance