title: Current status of endoscopic resection strategy for large, early colorectal neoplasia in Japan.
abstract: BACKGROUND
  Conventional endoscopic resection (CER) for early colorectal neoplasia (CRN) is widely accepted as a minimally invasive treatment. Endoscopic submucosal dissection (ESD) was developed in Japan to resect larger lesions, but ESD was not covered by the Japanese national health insurance until April 2012. In addition, treatment strategies vary considerably among medical facilities. To evaluate the current situation in Japan regarding endoscopic treatment of CRNs measuring ≥20 mm, we conducted a prospective multicenter study at 18 medium-volume and high-volume specialized facilities in cooperation with the Japan Society for Cancer of the Colon and Rectum (JSCCR).
  
  
  METHODS
  The JSCCR conducted a multicenter, observational study of all patients treated by CER and ESD of CRNs measuring ≥20 mm.
  
  
  RESULTS
  From October 2007 to December 2010, CERs and ESDs were performed on 1,845 CRNs (CERs 1,029; ESDs 816). Lesions diagnosed as protruded, flat, and depressed totaled 541, 1224, and 48, respectively. En bloc resection rates and mean procedure times for CER/ESD were 56.9%/94.5% (P < 0.01) and 18 ± 23 min/96 ± 69 min, respectively. The average ESD procedure time was 129 ± 83 min in the ≥40-mm group. As lesion size increased, the CER en bloc resection rate decreased significantly (trend P < 0.01), but the ESD en bloc resection rate remained over 93%. Perforation and delayed bleeding rates of CER/ESD were 0.8%/1.6% (P < 0.05) and 2%/2.2% (P = 0.3), respectively.
  
  
  CONCLUSIONS
  The en bloc resection rate for ESD was significantly higher than for CER, although complication rates were fairly low. Despite a longer procedure time, safety of colorectal ESD has improved in various facilities in Japan. However, ESD for lesions measuring ≥40 mm must be performed by experienced endoscopists due to the longer procedure time.
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan. tnakajim@ncc.go.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakajima
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Saito
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iishi
authors.forename: Shin-ei
authors.initials: SE
authors.lastname: Kudo
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ikematsu
authors.forename: Masahiro
authors.initials: M
authors.lastname: Igarashi
authors.forename: Yuusuke
authors.initials: Y
authors.lastname: Saitoh
authors.forename: Yuji
authors.initials: Y
authors.lastname: Inoue
authors.forename: Kiyonori
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Hisasbe
authors.forename: Takahisa
authors.initials: T
authors.lastname: Matsuda
authors.forename: Hideki
authors.initials: H
authors.lastname: Ishikawa
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Sugihara
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome