Commentary

Lesions involving the appendiceal orifice are a challenge for endoscopists. Risk factors for incomplete resection include involvement of more than 50 % of the orifice and deep involvement of the appendiceal lumen [1]. In the accompanying video, Uchima et al. [2] exclude high risk surface features, then visualize and confirm the extent of the lesion within the lumen before proceeding to resection. Partway through, they discover that the lesion extends more deeply than expected; however they meticulously ensure that all visible lesion is exposed and removed. This is essential, as incomplete resection may leave residual tissue deep in the appendix which may still harbor cancer, or be inaccessible at surveillance colonoscopy. If deep lumen involvement is confirmed, then surgical resection should be the treatment of choice, primarily because endoscopic resection will fail, but also because of the risk of covert malignancy. In a prospective cohort of 38 appendiceal orifice lesions referred for standard endoscopic mucosal resection (EMR), 12 lesions had deep lumen involvement and 2 of these were found to have cancer after surgical resection [1]. Endoscopic techniques for resection of lesions deeply involving the appendiceal orifice, such as endoscopic submucosal dissection and full-thickness resection, have been described [3] [4] [5]; however these approaches have a higher rate of surgery for complications and should be carefully discussed with the patient who may prefer to proceed to definitive surgical resection without the requirement for surveillance.

This video neatly demonstrates the underwater EMR technique that has been shown to have good outcomes in previous prospective series [6], and that are similar to those of standard EMR [1]. Whatever technique is used, the advice is the same – make sure you see it all, and make sure you remove it all!

Publication History

Article published online:
25 February 2021

• 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.e2
• 2 Uchima H, Colan-Hernandez J, Caballero N. et al. Underwater endoscopic mucosal resection of an adenomatous lesion with deep extension into the appendiceal orifice. Endoscopy 2020; 52
• 3 Oung B, Rivory J, Chabrun E. et al. ESD with double clips and rubber band traction of neoplastic lesions developed in the appendiceal orifice is effective and safe. Endosc Int Open 2020; 08: E388-E395
• 4 Bronzwaer M, Bastiaansen B, Koens L. et al. Endoscopic full-thickness resection of polyps involving the appendiceal orifice: a prospective observational case study. Endosc Int Open 2018; 06: E1112-E1119
• 5 Schmidbaur S, Wannhoff A, Walter B. et al. Risk of appendicitis after endoscopic full-thickness resection of lesions involving the appendiceal orifice: a retrospective analysis. Endoscopy 2020; 52
• 6 Binmoeller KF, Hamerski CM, Shah JN. et al. Underwater EMR of adenomas of the appendiceal orifice (with video). Gastrointest Endosc 2016; 83: 638-642