title: Endoscopic submucosal dissection in large sessile lesions of the rectosigmoid: learning curve in a European center.
abstract: OBJECTIVE
  Endoscopic submucosal dissection (ESD) in the colorectum is not currently a standard procedure. Few data are available from the Western world. The aim of the present study was to report on the first experiences and the learning curve of colorectal ESD in a European center.
  
  
  METHODS
  A total of 82 rectosigmoid lesions were referred for ESD. Lesion characteristics, resection rates, procedure times, complications, and recurrences were recorded prospectively. Results were compared between three consecutive study periods in order to determine the learning curve.
  
  
  RESULTS
  Lesions were located in the rectum (86.6 %) and the sigmoid colon (13.4 %). Median diameter was 45.5 mm. Lesions were of Paris type 0-Is with pit pattern type V (n = 8), 0-IIa (n = 33), 0-IIa + Is (n = 36), and 0-IIa + IIc (n = 5). The malignancy rate in these groups was 100 %, 0 %, 14 %, and 20 %, respectively. ESD was possible in 76 lesions (92.7 %). En bloc resection rate and R0 resection rate were 81.6 % and 69.7 %, respectively. Median procedure time was 176 minutes. Between the three consecutive study periods, en bloc resection rate increased (60.0 %, 88.0 %, 96.2 %), R0 resection rate increased (48.0 %, 76.0 %, 84.5 %; P < 0.001), and procedure time decreased (200, 193, 136 minutes; P = 0.027). The perforation and bleeding rates were 1.3 % and 7.9 %, respectively. Recurrence risk was 0 % after R0 en bloc resection and 41.7 % after piecemeal resection (P < 0.05). Median follow-up was 23.6 months.
  
  
  CONCLUSIONS
  In the European setting, ESD in the distal colon is feasible with acceptable complication risks. Resection rates were not as high as those from Japanese studies; however, a clear learning curve could be shown. Colorectal ESD needs to be further evaluated, particularly in Europe where ESD experience is low.
authors.affiliation: Department of Gastroenterology, Klinikum Augsburg, Stenglinstrasse 2, Augsburg, Germany. andreas.probst@klinikumaugsburg.de
authors.forename: A
authors.initials: A
authors.lastname: Probst
authors.forename: D
authors.initials: D
authors.lastname: Golger
authors.forename: M
authors.initials: M
authors.lastname: Anthuber
authors.forename: B
authors.initials: B
authors.lastname: Märkl
authors.forename: H
authors.initials: H
authors.lastname: Messmann
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D016063:Blood Loss, Surgical; D012809:Colon, Sigmoid / Q000473:pathology / Q000601:surgery; D003113:Colonoscopy / Q000009:adverse effects / Q000379:methods / Q000592:standards; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D004210:Dissection / Q000009:adverse effects / Q000379:methods; D005060:Europe; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery; D007416:Intestinal Perforation / Q000209:etiology*; D059032:Learning Curve; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D058996:Quality Improvement; D012007:Rectum / Q000473:pathology / Q000601:surgery; D055502:Secondary Prevention; D013997:Time Factors