Post written by Hsiyuan Chien,¹ MD, and Kenichiro Imai,² MD
¹Division of Gastroenterology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan ²Division of Endoscopy, Shizuoka Cancer Center, Shizuoka Japan
In this video case, colonoscopy in a 42-year-old-female showed a lateral spreading tumor granular homogeneous type, 30mm in diameter at the ascending colon. Narrow-band imaging (NBI) with magnifying endoscopy showed a capillary pattern type II by Sano’s classification. Chromoendoscopy with indigocarmine spray demonstrated a type 3L+4 pit pattern by Kudo’s classification. The diagnosis was adenoma and we decided to perform an EMR. After submucosal injection, a spot-shaped mucosal incision proximal to the tumor was done with a snare tip. By keeping the snare tip into the submucosal layer, the snare was fixed without slipping away. Complete en bloc resection was achieved with no adverse event. Pathology revealed a high-grade adenoma with tumor free margins. En bloc R0 resection for colonic lesions larger than 20mm is technically challenging by using conventional endoscopic mucosal resection (EMR) because of easy slippage during snaring and limited size and shape of snare. Moreover, in snare-EMR for large lesions, perforation is the major concern. This case illustrates a successful R0 resection by tip-in EMR for a large colonic flat adenoma.
Figure 1. Substantial submucosal injection (8 shots and estimated total amounts of 12 mL) was completed during tip-in EMR for a laterally spreading tumor, granular homogeneous type, 30 mm in diameter at the ascending colon.
By using tip-in EMR technique, en bloc R0 resection of large colonic tumors could be achieved in a relatively faster, safer and easier manner than endoscopic submucosal dissection (ESD) in certain selected cases. It will help endoscopists who have no experience of ESD or who are lack of optimal ESD equipments to treat large flat colonic tumors successfully.
In the future, characteristics (size or morphology) of success cases in Tip-in EMR should be clarified and a direct comparison of Tip-in EMR versus conventional EMR is warranted.