Beyond the snare: technically accessible large en bloc colonic resection in the West: an animal study.
BACKGROUND
Endoscopic submucosal dissection (ESD) and circumferential submucosal incision endoscopic mucosal resection (CSI-EMR) are techniques for en bloc excision of large sessile colonic lesions. Our aims were to compare the efficacy, safety and learning curve of colonic hybrid knife (HK) ESD versus CSI-EMR for en bloc excision of 50 mm diameter hemi-circumferential artificial lesions in a porcine model.


METHODS
Two separate 50 mm diameter areas of normal recto-sigmoid mucosa were marked out in each of ten pigs. One was excised with HK-ESD using succinylated gelatin (SG) submucosal injection. The other was isolated with CSI with the Insulated Tip Knife 2 followed by SG submucosal injection then EMR with a large snare. Euthanasia and colectomy was performed at 72 h followed by blinded histopathology assessment.


RESULTS
En bloc excision rates were: HK-ESD 100% versus CSI-EMR 20% (P = 0.008). The mean number of resections per lesion was HK-ESD 1 versus CSI-EMR 3 (P = 0.001). The mean dimensions of the largest specimen per technique were HK-ESD 63 × 54 mm versus CSI-EMR 49 × 41 mm (P = 0.005). Procedure duration mean was HK-ESD 54 min versus CSI-EMR 22 min (P < 0.001). When procedure duration was adjusted for the size of the resected en bloc specimen, a statistically significant and accelerated learning effect was noted for HK-ESD (r = -0.83, P = 0.003). There were no perforations and no significant bleeding.


CONCLUSIONS
HK-ESD with SG submucosal injection is superior to CSI-EMR for en bloc excision of 50 mm diameter lesions in a porcine model. The technique is rapidly learnt. This novel approach may lower the barrier to colonic ESD for Western endoscopists.
Department of Gastroenterology and Hepatology, Westmead Hospital, Sydney, New South Wales, Australia.
Alan
A
Moss
Michael J
MJ
Bourke
Andrew J
AJ
Metz
Duncan
D
McLeod
Kayla
K
Tran
Craig
C
Godfrey
Gary
G
McKay
Abhilash P
AP
Chandra
Asokan
A
Pasupathy
D000818:Animals; D003082:Colectomy; D003106:Colon / Q000601:surgery*; D003113:Colonoscopy / Q000295:instrumentation / Q000379:methods*; D004210:Dissection / Q000379:methods; D005780:Gelatin; D007413:Intestinal Mucosa / Q000601:surgery; D008751:Methylene Blue; D013386:Succinates; D013525:Surgical Instruments; D013552:Swine
D013386:Succinates; C060085:succinylated gelatin; D005780:Gelatin; D008751:Methylene Blue