title: Therapeutic outcomes of endoscopic submucosal dissection of undifferentiated-type intramucosal gastric cancer without ulceration and preoperatively diagnosed as 20 millimetres or less in diameter.
abstract: OBJECTIVE
  The aim of the present study was to examine therapeutic outcomes of endoscopic submucosal dissection (ESD) of undifferentiated-type intramucosal gastric cancer and the problems of diagnosis.
  
  
  METHODS
  We reviewed 58 patients with preoperatively diagnosed undifferentiated-type intramucosal early gastric cancer (EGC) without ulceration with a diameter of 20 mm or smaller (expanded-indication lesion) who underwent ESD at the Cancer Institute Hospital between September 2003 and August 2008.
  
  
  RESULTS
  The overall rates of one-piece resection and complete resection were 98% and 90% respectively, and the median operation time was 70 min. Bleeding was seen in 8.6% and perforation in 3.4%. The curative resection rate was low at 79%. Factors responsible for non-curative resection were most commonly submucosal invasions. If limited to pathologically diagnosed expanded-indication lesions, the curative resection rate was 98%. The difference in tumor size between a macroscopic diameter and a histological diameter was within +/-5 mm in 96% of expanded-indication lesions, with none of these cases having a histological diameter that exceeded the macroscopic diameter by more than 5 mm.
  
  
  CONCLUSIONS
  ESD was technically feasible for expanded-indication lesions of undifferentiated-type EGC. We achieved a high rate of curative resection by the markings at sites 5 mm beyond the preoperatively determined lesion area. Factors responsible for non-curative resection were most commonly submucosal invasions. We should diagnose the depth of such lesions more carefully.
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Tokyo. yorimasa.yamamoto@jfcr.or.jp <yorimasa.yamamoto@jfcr.or.jp>
authors.forename: Yorimasa
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Junko
authors.initials: J
authors.lastname: Fujisaki
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Hirasawa
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Ishiyama
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Yoshimoto
authors.forename: Nobue
authors.initials: N
authors.lastname: Ueki
authors.forename: Akiko
authors.initials: A
authors.lastname: Chino
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Tsuchida
authors.forename: Etsuo
authors.initials: E
authors.lastname: Hoshino
authors.forename: Naoki
authors.initials: N
authors.lastname: Hiki
authors.forename: Tetsu
authors.initials: T
authors.lastname: Fukunaga
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sano
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Miyata
authors.forename: Noriko
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Yo
authors.initials: Y
authors.lastname: Kato
authors.forename: Masahiro
authors.initials: M
authors.lastname: Igarashi
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D004210:Dissection; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology / Q000601:surgery; D005773:Gastroscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery*; D016896:Treatment Outcome