title: Endoscopic submucosal dissection as total excisional biopsy for clinical T1 colorectal carcinoma.
abstract: OBJECTIVE
  Only the depth of submucosal invasion can be estimated prior to determining the indications for endoscopic submucosal dissection (ESD) as a curative treatment for colorectal carcinoma (CRC). Here we evaluated the outcomes of ESD for clinical T1 CRCs.
  
  
  METHODS
  Of 660 patients who underwent ESD for CRC at the Hiroshima University Hospital between June 2003 and December 2013, we examined the outcomes of 37 (6%; 26 men, 11 women; mean age ± SD, 68 ± 12 years) who underwent ESD as total excisional biopsy for various reasons, in spite of an endoscopic diagnosis of T1 CRC.
  
  
  RESULTS
  The mean lesion size was 25 ± 14 mm; 14 lesions were protruding and 23 were superficial. The en bloc resection rate was 100% (37/37). The histological en bloc resection rate was 92% (34/37). ESD resulted in a positive vertical margin in 3 cases. Deep submucosal invasion was seen in 3 cases, 2 of which had severe submucosal fibrosis. Although severe submucosal fibrosis was not found in other cases, pathologic examination of the deepest invasive portion of the tumor revealed poorly differentiated adenocarcinoma. The rates of post-ESD bleeding and perforation were 8% (3/37) and 5% (2/37), respectively. All patients recovered under conservative therapy. No cases of recurrence were noted in patients without additional surgical resection when the lesions satisfied the curative conditions listed in the 2014 Japanese Society for Cancer of the Colon and Rectum guidelines.
  
  
  CONCLUSIONS
  En bloc resection by ESD as total excisional biopsy for clinical T1 CRC is a highly effective treatment and establishes a precise histological diagnosis.
authors: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan.
authors: Naoki
authors: N
authors: Asayama
authors: Shiro
authors: S
authors: Oka
authors: Shinji
authors: S
authors: Tanaka
authors: Nana
authors: N
authors: Hayashi
authors: Koji
authors: K
authors: Arihiro
authors: Kazuaki
authors: K
authors: Chayama
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology; D000368:Aged; D001706:Biopsy; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D017408:Guidelines as Topic; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology* / Q000601:surgery*; D007564:Japan; D008197:Lymph Node Excision / Q000379:methods*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D012189:Retrospective Studies; D016896:Treatment Outcome