title: Useful condition of chromoendoscopy with indigo carmine and acetic acid for identifying a demarcation line prior to endoscopic submucosal dissection for early gastric cancer.
abstract: BACKGROUND
  Identifying a precise demarcation line (DL) is indispensable for pathological complete en bloc endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). We evaluated the useful condition of chromoendoscopy with indigo carmine and acetic acid for marking dots around lesions before ESD for EGC.
  
  
  METHODS
  We examined 98 consecutive patients with 109 intramucosal EGCs (mean diameter, 17.8 ± 12.4 mm; main histologic type, 96 intestinal and 13 diffuse) resected by en bloc ESD after chromoendoscopy with indigo carmine and acetic acid between December 2012 and February 2014. The DL was identified by this technique just before ESD (mean chromoendoscopy observation time, 71.6 s); subsequently, marking dots were placed around the EGC. EGCs were classified into two groups: useful for identifying the DL or useless. Clinicopathological characteristics and clinical outcomes were evaluated in each group.
  
  
  RESULTS
  Forty-two of the 109 cases (38.5 %) were determined useful for chromoendoscopy with indigo carmine and acetic acid. Multivariate analysis with logistic regression showed that macroscopic type (protruded or flat elevated-type) and atrophic border (the oral side of tumor) were independently associated with the usefulness of chromoendoscopy using indigo carmine and acetic acid for identifying the DL of EGCs (P < 0.05). The histologically positive horizontal margin after ESD was 0 % (0/42) in useful cases, and 7.5 % (5/67) in useless cases.
  
  
  CONCLUSIONS
  Before ESD, chromoendoscopy with indigo carmine and acetic acid can be used for creating precise markings in protruded or flat elevated-type EGC or at the atrophic border on the oral side of EGCs.
authors.affiliation: Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Norifumi
authors.initials: N
authors.lastname: Numata
authors.affiliation: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan. oka4683@hiroshima-u.ac.jp.
authors.forename: Shiro
authors.initials: S
authors.lastname: Oka
authors.affiliation: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanaka
authors.affiliation: Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Yoshifuku
authors.affiliation: Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Miwata
authors.affiliation: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Sanomura
authors.affiliation: Department of Pathology, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Arihiro
authors.affiliation: Faculty of Human Culture and Science, Prefectural University of Hiroshima, Hiroshima, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Shimamoto
authors.affiliation: Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
mesh_terms: D019342:Acetic Acid; D000368:Aged; D000069916:Endoscopic Mucosal Resection / Q000379:methods*; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D005752:Gastric Mucins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007203:Indigo Carmine; D008297:Male; D008875:Middle Aged; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery*
chemical_list: D005752:Gastric Mucins; D007203:Indigo Carmine; D019342:Acetic Acid
keywords: Acetic acid; Chromoendoscopy; Endoscopic submucosal dissection; Gastric cancer