Current guidelines recommend endoscopic resection for superficial colorectal neoplasia
in patients with ulcerative colitis, particularly for a clearly visible lesion with
distinct margins [1]. However, endoscopic removal of colorectal polyps is technically challenging in
patients with ulcerative colitis. Endoscopic submucosal dissection (ESD) enables complete
removal of such polyps but presents some technical difficulties and is time consuming
[2].
A 73-year-old man with pancolitis-type ulcerative colitis maintained remission with
the administration of oral and rectal 5-aminosalicylate and underwent colonoscopy
for surveillance. We observed no active mucosal inflammation over the entire colon.
However, there was a 15-mm flat elevated lesion in the sigmoid colon. Biopsy of the
lesion suggested low-grade adenoma. Colonoscopy after 2 months revealed a 15-mm lesion
with a scar caused by the previous biopsy ([Fig. 1]). Narrow-band imaging magnifying endoscopy showed regular vessels and surface structures
with clear demarcation, thus indicating an adenoma ([Fig. 2]). Submucosal fibrosis caused by previous inflammation and biopsies made complete
removal using conventional endoscopic resection, such as endoscopic mucosal resection
(EMR) and ESD, difficult. We performed underwater EMR (UEMR) for the lesion ([Fig. 3]; [Video 1]) [3]. En bloc resection was achieved without any complications. Histopathological examination
revealed complete removal of the low-grade tubular adenoma with severe fibrosis in
the submucosal layer ([Fig. 4]).
Fig. 1 Colonoscopy shows a 15-mm, flat, elevated lesion with a scar located in the sigmoid
colon.
Fig. 2 Narrow-band imaging magnifying endoscopy shows regular vessels and surface structures,
classified as type 2A according to the Japan Narrow-Band Imaging Expert Team classification.
Fig. 3 Water immersion provides a “float” effect, floating the lesion away from the muscularis
layer, thus allowing wide-field resection of the polyp.
Video 1 Colorectal polyp in a patient with ulcerative colitis is removed by underwater endoscopic
mucosal resection. This eliminates the need for submucosal injection and provides
a “floating” effect that facilitates the snaring of the scarred polyp.
Fig. 4 Microscopic findings show excision of a low-grade tubular adenoma with negative margin.
Submucosal fibrosis makes recognizing an adequate depth for dissection in ESD difficult
[4]. However, UEMR eliminates the need for submucosal injection. The “floating” and
“heat-sink” effects facilitate the grasping and removal of large or scarred polyps
[5]. This is the first case to demonstrate the usefulness of UEMR for the management
of superficial colorectal neoplasia in patients with ulcerative colitis. Thus, UEMR
can be considered a safe, time-saving, and effective option.
Endoscopy_UCTN_Code_TTT_1AQ_2AD
Endoscopy E-Videos is a free 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.
This section has its own submission
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https://mc.manuscriptcentral.com/e-videos
