Underwater endoscopic mucosal resection of an adenomatous lesion with deep extension into the appendiceal orifice

Endoscopic mucosal resection (EMR) of lesions involving the appendiceal orifice is technically challenging because of poor endoscopic access due to the narrow lumen of the appendix. This brings a high risk of perforation because of the thin colonic wall at the base of the cecum.

In expert hands, EMR is a safe and effective treatment of laterally spreading tumors (LST) surrounding the appendiceal orifice, but if more than 50 % of the circumference of the orifice is involved, surgery should be considered [1].

Underwater EMR (UEMR), described by Binmoeller et al. in 2012 [2], has been shown to enable safe resection of appendiceal orifice lesions, especially those limited to the rim. It allows endoscopic resection without previous submucosal injection, as the colonic lesion “floats” in a lumen filled with water, making lesions involving the appendiceal orifice more accessible to endoscopic resection [3].

Herein we present a case of a 73-year-old man referred to our unit for treatment of a “donut”-shaped granular-type LST completely encircling the AO. No deep submucosal invasion signs were observed ([Fig. 1]).

Fig. 1 “Donut”-shaped laterally spreading tumor under narrow-band imaging.

UEMR was performed using room-temperature sterile water to fill the lumen and a 15-mm stiff, rounded snare (Captivator II; Boston Scientific, Voisins-le-Bretonneux, France) through a single-channel colonoscope using AutoCut Mode (VIO 3; Erbe Elektromedizin, Tübingen, Germany) ([Video 1]). During the procedure, deep extension into the appendiceal orifice was observed. After a combination of air suction and more water infusion, the deep residual tissue everted, making it accessible for snare resection.

Video 1 Underwater endoscopic mucosal resection of a “donut”-shaped laterally spreading tumor involving the appendiceal orifice.

The procedure lasted 24 min and the patient was discharged after 2 h without complications. The histological diagnosis was low-grade dysplasia adenoma.

Follow-up colonoscopy after 6 months showed no residual lesion ([Fig. 2]).

Fig. 2 Postresection scar after 6 months showing no residual tissue. Narrow-band imaging.

UEMR may allow safe complete endoscopic resection in cases of nonmalignant lesions with deep extension into the appendiceal orifice.

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Publication History

Article published online:
13 July 2020

• References

• 1 Tate DJ, Desomer L, Awadie H. et al. EMR of laterally spreading lesions around or involving the appendiceal orifice: technique, risk factors for failure, and outcomes of a tertiary referral cohort (with video). Gastrointest Endosc 2018; 87: 1279-1288
• 2 Binmoeller KF, Weilert F, Shah J. et al. “Underwater” EMR without submucosal injection for large sessile colorectal polyps (with video). Gastrointest Endosc 2012; 75: 1086-1091
• 3 Binmoeller KF, Hamerski CM, Shah JN. et al. Underwater EMR of adenomas of the appendiceal orifice (with video). Gastrointest Endosc 2016; 83: 638-642