Subscribe to RSS
Underwater endoscopic mucosal resection after endoscopic ultrasound examination for safe and reliable complete resection of a deeply invasive submucosal cecal cancer
The risk of lymph node metastases from invasive submucosal (T1b) colorectal cancers > 1000 µm deep is 1.3 % according to the Japanese guideline . Over 98 % of stage T1b cancers without evidence of lymphovascular invasion, poor differentiation, or budding have no associated lymph node metastases. Achieving an endoscopic R0 resection allows curative resection of the majority of stage T1b cancers. Although magnifying colonoscopy can diagnose stage T1b cancers, pathological evaluation using specimens from an R0 resection is more reliable. If a cancer is diminutive and possibly a stage T1b cancer, total excision for pathological evaluation may avoid surgical resection but, to be justified, must be safe and reasonable. Although endoscopic submucosal dissection is reliable for R0 resection, Fukuda et al. recently showed that underwater endoscopic mucosal resection (UEMR) can completely resect stage T1b lesions . Endoscopic ultrasound (EUS) demonstrates the submucosa under the tumor, which facilitates decision-making about UEMR.
A 73-year-old man was referred because of a cecal lesion that was suspected to be an adenocarcinoma after biopsy. An outpatient colonoscopy revealed a 7-mm sessile cecal tumor. Magnifying narrow-band imaging using an EC-760ZP-W/M colonoscope (Fujifilm, Tokyo, Japan) with distal attachment (D-201-14304; Olympus, Tokyo, Japan) suggested a T1b cancer ([Fig. 1]; [Video 1]). EUS (EU-ME1; Olympus) clearly demonstrated residual submucosa under the tumor. When the cecum contracted, the muscularis became recessed circumferentially, with a thickened submucosa on EUS imaging. This transformed the lesion into a floating subpedunculated tumor in the underwater endoscopic view ([Fig. 2]), which suggested that complete endoscopic resection using UEMR for complete pathological evaluation would be both safe and feasible on an outpatient basis. UEMR was completed without complications ([Fig. 3]). Pathologic evaluation revealed a submucosal invasive adenocarcinoma with negative margins ([Fig. 4]).
Video 1 Underwater endoscopic mucosal resection is performed for an endoscopically identified deeply invasive cancer after it has been confirmed to be both safe and feasible on endoscopic ultrasound.
This patient demonstrates that a stage T1b cancer can be safely and completely resected with UEMR after first confirming the submucosal characteristics using EUS. Indiscriminate EMR and/or cold snare polypectomy should be avoided for such lesions.
Endoscopy E-Videos is an open access online section, reporting on interesting cases and new techniques in gastroenterological endoscopy. All papers include a high quality video and all contributions are freely accessible online. Processing charges apply (currently EUR 375), discounts and wavers acc. to HINARI are available.
This section has its own submission
Article published online:
13 May 2022
© 2022. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)
Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany
- 1 Hashiguchi Y, Muro K, Saito Y. et al. Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2019 for the treatment of colorectal cancer. Int J Clin Oncol 2020; 25: 1-42
- 2 Fukuda H, Takeuchi Y, Shoji A. et al. Curative value of underwater endoscopic mucosal resection for submucosally invasive colorectal cancer. J Gastroenterol Hepatol 2021; 36: 2471-2478