UNDERWATER ENDOSCOPIC MUCOSAL RESECTION (UEMR) FOR COLORECTAL LESIONS IN CHALLENGING SITUATIONS

Aims:

To study the safety, feasibility and technical success of UEMR for challenging colorectal lesions.

Methods:

Demographic, clinical, endoscopic and histological data were collected from patients that underwent UEMR between May 2016 and September 2017 in 3 hospitals. UEMR was performed according to the technique described by Binmoeller, with some minor modifications. All the lesions with nonlifting sign, involvement of appendix orifice and ileocecal valve were included in this study. Technical success was defined as a complete resection of the visible lesion at the index procedure.

Results:

20 UEMR were performed. The mean age of the patients was 66 years (35 – 90, SD 13,4), with men being 80%.

The table summarizes the indications and technical success of the UEMR.

Tab. 1:

Technical succes of the lesions treated by UEMR

Lesions treated by UEMR (N = 20)	Untreated cecal lesion involving the appendix border < 75% (N = 2)	Untreated cecal lesion extending into the appendix (N = 3)	Recurrent/Residual nonlifting ICV lesions without or with non-extensive involvement of terminal ileal mucosa (N = 4)	Other recurrent/Residual nonlifting lesions (N = 9)	Untreated nonlifting lesions (N = 2)
Technical success	2 (100%)	2 (66,7%)	4 (100%)	9 (100%)	2 (100%)
Median size mm (range)	12,5 (7 – 18)	28 (5 – 65)	15 (10 – 25)	12 (4 – 20)	20 (10 – 30)
Final outcomes	No recurrences to date	One case underwent appendectomy for residual lesion. No recurrences in the rest.	One recurrence in one case with nonextensive ileal involvement.	No recurrences to date	One case underwent surgery for deep submucoal adenocarcinoma. The other case present no recurrence.

Histology showed no malignancy except in one case of untreated nonlifting lesions (prior histology showed low grade dysplasia), that was an adenocarcinoma with deep submucosal invasion. There was one lesion with deep extension into the appendiceal orifice that could not be completely resected. In this two cases the patients were referred to surgery. There were no perforations or clinical relevant post-procedural bleeding. The median of the colonoscopic follow-up was 6 months.

Conclusions:

UEMR might be a safe and feasible technique for some challenging colorectal lesions. As it is a water immersion technique it avoids the need for submucosal injection before resection, and that may be helpful to work in challenging situations such as nonlifting lesions, lesions involving the appendiceal orifice or the ileocecal valve.