Endoscopy 2022; 54(03): E88-E89
DOI: 10.1055/a-1381-6915
E-Videos

Utility of under-gel endoscopic mucosal resection with partial submucosal injection for a laterally spreading tumor

1   Department of Gastroenterology, St. Luke’s International Hospital, Tokyo, Japan
,
Naoki Kanomata
2   Department of Pathology, St. Luke’s International Hospital, Tokyo, Japan
,
1   Department of Gastroenterology, St. Luke’s International Hospital, Tokyo, Japan
› Institutsangaben
 

Conventional endoscopic mucosal resection (EMR) is a widely used technique in the treatment of colorectal tumors. When resecting laterally spreading tumors (LSTs) with conventional EMR, the distal edge is difficult to dissect and tends to be piecemealed. However, the nongranular pseudodepressed type (LST-NG-PD) has a high risk of malignancy, requiring en bloc resection [1]. Endoscopic submucosal dissection (ESD) can ensure high en bloc resection rates, but it also has drawbacks such as high perforation rates, high cost, and long procedure times. Binmoeller et al. introduced underwater EMR (UEMR) as a useful alternative to ESD for LSTs [2]; however, treating the distal end remains a challenge and could cause segmental resection. In addition, the use of water in UEMR may impair clarity of view if bleeding occurs. Partial submucosal injection improves visualization of the distal edge [3], and gel immersion improves the endoscopic visual field [4] [5]. Here, we report that under-gel EMR with partial submucosal injection is an effective means of achieving en bloc resection of LST-NG-PD ([Video 1]).

Video 1 Laterally spreading tumor of the nongranular pseudodepressed type effectively treated by a combined method of under-gel endoscopic mucosal resection with partial submucosal injection.

A 43-year-old woman was referred to our hospital for treatment of a colonic tumor. The lesion was observed in the rectosigmoid ([Fig. 1]). Because of poor scope maneuverability and difficulty visualizing the distal edge, a partial submucosal injection was performed along the distal edge of the lesion ([Fig. 2]). Initially, UEMR was considered, but the rapid mixing of fresh blood with water compromised visibility; therefore, we used Viscoclear gel (Otsuka Pharmaceuticals Factory, Inc., Japan). The lesion was successfully captured by an electrocautery snare ([Fig. 3]) and resected without remnant ([Fig. 4]). The histopathological diagnosis was well-differentiated tubular adenocarcinoma, and the histopathology was negative for vertical and horizontal margins ([Fig. 5]). In this case, under-gel EMR with partial submucosal injection was effective for LST.

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Fig. 1 A 16-mm laterally spreading tumor (LST) was found in the rectosigmoid colon. Using indigo carmine dye, a central depression was revealed on the surface of the polyp, which was classified as the nongranular pseudodepressed type of LST.
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Fig. 2 Partial submucosal injection of sodium hyaluronate was performed only along the distal edge of the lesion.
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Fig. 3 Intraluminal air was removed, the colon was filled with water, but the mixing of blood from the lesion with the water compromised visibility. Therefore, Viscoclear gel was used. The viscosity of the gel improved the poor visual field and the lesion, including the distal edge, was successfully captured with an electrocautery snare.
Zoom
Fig. 4 Resected specimen. Yellow arrows show the distal edge of the lesion. The distal end was adequately resected due to use of a partial submucosal injection technique to improve its visibility.
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Fig. 5 The histopathological diagnosis was well-differentiated tubular adenocarcinoma, and the histopathology was negative for vertical and horizontal margins.

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Competing interests

The authors declare that they have no conflict of interest.


Corresponding author

Kazuki Yamamoto, MD
Department of Gastroenterology
St. Luke’s International Hospital
9-1 Akashi-cho, Chuo-ku
Tokyo 104-8560
Japan   

Publikationsverlauf

Artikel online veröffentlicht:
15. März 2021

© 2021. Thieme. All rights reserved.

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Zoom
Fig. 1 A 16-mm laterally spreading tumor (LST) was found in the rectosigmoid colon. Using indigo carmine dye, a central depression was revealed on the surface of the polyp, which was classified as the nongranular pseudodepressed type of LST.
Zoom
Fig. 2 Partial submucosal injection of sodium hyaluronate was performed only along the distal edge of the lesion.
Zoom
Fig. 3 Intraluminal air was removed, the colon was filled with water, but the mixing of blood from the lesion with the water compromised visibility. Therefore, Viscoclear gel was used. The viscosity of the gel improved the poor visual field and the lesion, including the distal edge, was successfully captured with an electrocautery snare.
Zoom
Fig. 4 Resected specimen. Yellow arrows show the distal edge of the lesion. The distal end was adequately resected due to use of a partial submucosal injection technique to improve its visibility.
Zoom
Fig. 5 The histopathological diagnosis was well-differentiated tubular adenocarcinoma, and the histopathology was negative for vertical and horizontal margins.