“Tip-in underwater endoscopic mucosal resection” without submucosal injection for superficial nonampullary duodenal adenomas

Underwater endoscopic mucosal resection (EMR) has been reported as an effective treatment for superficial nonampullary duodenal adenomas [1] [2]. However, the en bloc and R0 resection rates have been relatively low [3], possibly because the floating center of the lesion can hinder the visualization of its distal edge. This can cause the snare tip to slip, making it difficult to capture the lesion and achieve en bloc resection. To overcome these challenges, we report our new technique of “tip-in underwater EMR” for superficial nonampullary duodenal adenomas.

A 63-year-old-man presented with a duodenal adenoma with a white opaque substance that was 20 mm in diameter and located in the superior duodenal angulus ([Fig. 1]). Saline was infused using a mechanical water pump (OFP-2; Olympus, Tokyo, Japan) ([Fig. 2 a]) to completely fill the lumen. The snare tip (Snaremaster; Olympus) was projected by 1–2 mm, and a mucosal incision was created on the distal edge of the lesion using a cutting current (Endo-cut I, Effect 2; VIO3, ERBE, Tubingen, Germany) ([Fig. 2 b]). The snare was then positioned around the lesion with gentle pushing ([Fig. 2 c]). After successful capture of the lesion, resection was performed using electrocautery (Endo-cut I, Effect 2). En bloc resection was achieved ([Fig. 2 d]) ([Video 1]). Pathological findings indicated a low-grade adenoma with negative margins.

Fig. 1 White light image showed a duodenal adenoma with white opaque substance.

Fig. 2 a The lumen was filled with saline. b The distal edge of the lesion was cut using a cutting current without any submucosal injections. c The snare was positioned around the lesion. d There was no residual lesion after resection.

Video 1 Tip-in underwater endoscopic mucosal resection for superficial nonampullary duodenal adenoma.

During tip-in EMR, making a pre-cut on the distal side of the lesion with prior submucosal injections and fixing the snare tip can make the snare less slippery [4] [5]. However, our new technique of “tip-in underwater EMR” was performed without submucosal injections. Theoretically, the heat sink effect of water, combined with a relatively thicker wall, may protect against a transmural burn even while making a pre-cut with the snare tip. We are currently planning a feasibility study to demonstrate the utility and safety of this novel method.

Endoscopy_UCTN_Code_TTT_1AO_2AG

Publication History

Article published online:
21 August 2023

• References

• 1 Binmoeller KF, Shah JN, Bhat YM. et al. “Underwater” EMR of sporadic laterally spreading nonampullary duodenal adenomas (with video). Gastrointest Endosc 2013; 78: 496-502
• 2 Yamasaki Y, Uedo N, Takeuchi Y. et al. Underwater endoscopic mucosal resection for superficial nonampullary duodenal adenomas. Endoscopy 2018; 50: 154-158
• 3 Takatori Y, Kato M, Masunaga T. et al. Feasibility study of partial submucosal injection technique combining underwater EMR for superficial duodenal epithelial tumors. Dig Dis Sci 2022; 67: 971-977
• 4 Imai K, Hotta K, Ito S. et al. Tip-in endoscopic mucosal resection for 15- to 25-mm colorectal adenomas: A single-center, randomized controlled trial (STAR Trial). Am J Gastroenterol 2021; 116: 1398-1405
• 5 Takada K, Hotta K, Imai K. et al. Tip-in EMR as an alternative to endoscopic submucosal dissection for 20- to 30-mm nonpedunculated colorectal neoplasms. Gastrointest Endosc 2022; 96: 849-856.e3