title: Early esophageal cancer can be detected by screening endoscopy assisted with narrow-band imaging (NBI).
abstract: OBJECTIVE
  Iodine staining of the esophagus has been shown to be useful in detecting esophageal cancer. Narrow band imaging (NBI), a new endoscopic lighting system, visualizes the microvasculature of the gastrointestinal (GI) mucosa. To evaluate the detectability of early esophageal cancer by screening endoscopy assisted with NBI as compared with that assisted with iodine staining.
  
  
  METHODS
  
  
  
  METHODS
  A prospective comparative study. Setting A single endoscopy unit.
  
  
  METHODS
  Forty-nine consecutive patients, consisting of 40 males and 9 females with a mean age of 67, most of whom were at high risks for esophageal cancer (heavy drinker and smoker, history of cancer especially of head and neck, etc.).
  
  
  METHODS
  Following conventional endoscopic observation, the esophagus was observed with NBI for possible cancerous lesions. Dark-brown areas on NBI were defined as NBI-positive areas. Esophageal mucosa was subsequently stained with 1.5% iodine, and both findings were compared. Finally, the areas discolored by iodine stain were biopsied for histological evaluation.
  
  
  METHODS
  The sensitivity, specificity, and positive predictive value (PPV) of endoscopic detection of esophageal cancer.
  
  
  RESULTS
  Squamous cell carcinoma was detected in 5 out of 118 areas. Esophageal cancers detected were all both NBI-positive and discolored by iodine staining. Sensitivity, specificity, and PPV of NBI-positive areas for cancer were 100%, 59%, and 9.8%, respectively. On the other hand, the discolored areas with iodine staining for cancer were 100%, 4.4%, and 4.4%, respectively. NBI observation was significantly superior to iodine staining for detecting esophageal cancer (p < 0.02).
  
  
  CONCLUSIONS
  In this study, the endoscopist engaged was not blinded and the assessment was not standardized.
  
  
  CONCLUSIONS
  Esophageal endoscopy assisted with NBI was more useful for detecting early esophageal cancer than that assisted with iodine staining.
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, 3-10-6 Ariake, Koto-ward, Tokyo 135-8550, Japan. kensuke.kuraoka@jfcr.or.jp
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kuraoka
authors.forename: Etsuo
authors.initials: E
authors.lastname: Hoshino
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Tsuchida
authors.forename: Junko
authors.initials: J
authors.lastname: Fujisaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Rikiya
authors.initials: R
authors.lastname: Fujita
mesh_terms: D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000473:pathology; D055088:Early Detection of Cancer; D004938:Esophageal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D004945:Esophagoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D007455:Iodine; D008297:Male; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013194:Staining and Labeling / Q000379:methods
chemical_list: D007455:Iodine