Introduction Submucosal desmoplasis post EMR confers the natural history of regenerative luminal healing. Index R1 or Rx dissections of colorectal neoplasia using either EMR, EPMR or simple snare polypepctomy complicated by remnant or recurrent intraepithelial is clinically challenging. Formal open surgical resection or ablation is usually inevitable in this cohort. We describe, using video presentation data, the technique of primary endoscopic fibrosis divissional dissection with curative intent for recurrent or remant intraepithelial neoplasia of the right-hemi colon post index EMR.

Methods Recurrent disease or refractory intraepithelial neoplasia was defined according to Higaki criteria. Patients were consented for progression to salvage dissection prior to endoscopy. Pre-resection peripheral margin APC ‘mark out’ was performed following index indigo carmine chromoscopy to deliniate the lesion’s horizontal axis with thermal mucosal tattoos placed 2–4 mm away from the lesion margin and within a type I crypt mucosal zone. Peripheral smi with 1/10,000 adrenaline solution was performed with 6 mm marginal circumfrential 6 mm incisions made to the level of the deep submucosal layer using the straight flex knife. Dissection of the exposed submucosal desmoplastic fibrosis layer was then performed using a fixed en face IT knife distance coupled with a blunt tractional endoscopic ‘tunnelling’ technique. Prophylactically, sm vessels were ablated or clipped prior to tissue recovery.

Results n = 12 patients. Paris class LST-NG/G (6)/0-IIa (6). Median operating time 64 mins (range 34–82). Median lesion size 22mm (range 12–46 mm). Asymetrical, partial or complete NL = 12 (100%). Perforation rate 0/12. Median hospital stay 24 hours (range 6–120). 30 day mortality 0%. R0 resection achieved in 11/12 (92%). Endoscopic recurrence rate 0% (median follow-up 18/12 (range 2–43 months). Post dissection late bleed occured in 3/12 (25%) of the cohort all treated conservatively. There were no cases of immediate or early dissection bleeding.

Conclusion Salvage endoscopic dissection of remnant or recurrent intraepithelial neoplasia post index EMR, EPMR or conventional polypectomy is technically possible in the UK in this pilot clinical experience. Dissection is however technically demanding, is complicated by a high delayed bleeding risk and is time consuming. In an appropriately selected patient cohort however this novel therapy may negate the need for formal surgical excision which in the elderly and those with significant comorbidity becomes an attractive therapeutic modality changing the paradigm away from palliative ablative methods in those unfit for formal surgical resection.

Disclosure of Interest None Declared.