Comparison of endoscopic submucosal dissection and endoscopic mucosal resection for large XXXX .

@entity5 @entity1 @entity86 @entity14
BACKGROUND AND AIMS: Endoscopic mucosal resection (EMR) is the standard procedure for treatment of @entity14 . Endoscopic submucosal dissection (ESD) can be performed for resection of larger @entity5 , but has not been studied in the colorectum because of technical difficulties and complications. We compared outcomes and complications after resection of @entity14 larger than 20 mm diameter by ESD and EMR. MATERIALS AND METHODS: We retrospectively studied 104 @entity14 treated with EMR from 1995 to 2004, and 85 @entity14 treated with ESD from 2005 to 2009. We compared the @entity5 location, shape, size, procedure time, en bloc resection rate, recurrence rate, and associated complications between the treatments. RESULTS: @entity5 treated with ESD were larger (31.6    9.0 vs. 25.5    6.8 mm, P<0.001), incurred a longer procedure time (87.2    49.7 vs. 29.4    26.1 min, P<0.001), had a higher en bloc resection rate [71 of 85 @entity5 (83.5%) vs. 50 of 104 @entity5 (48.1%), P<0.001], and had a lower recurrence rate [one of 84 @entity5 (1.2%) vs. 16 of 104 @entity5 (15.4%); P=0.002] compared with EMR. Perforation occurred in five (5.9%) cases after ESD and in none after EMR (P=0.04). @entity86 occurred in two (2.4%) and three (2.9%) cases after ESD and EMR (P=not significant), respectively. Although 11 of 16 cases with recurrence after EMR were cured by additional endoscopic treatment, three cases required surgery. The only recurrence after ESD was in one @entity1 who developed perforation after snare EMR. CONCLUSION: Despite its longer procedure time and higher perforation rate, ESD resulted in a higher en bloc resection rate and lower recurrence rate for larger @entity14 compared with EMR.
