Diagnostic endoscopic submucosal dissection for colorectal lesions with suspected deep invasion.

BACKGROUND: Endoscopic submucosal dissection (ESD) is potentially a curative treatment for T1 colorectal cancer under certain conditions. The aim of this study was to evaluate the feasibility and effectiveness of ESD for lesions with a suspicion of focal deep invasion. METHODS: In this retrospective multicenter study, consecutive patients with colorectal neoplasia displaying a focal (< 15 mm) deep invasive pattern (FDIP) that were treated by ESD were included. We excluded ulcerated lesions (Paris III), lesions with distant metastasis, and clearly advanced tumors (tumoral strictures). RESULTS: 124 patients benefited from 126 diagnostic dissection attempts for FDIP lesions. Dissection was feasible in 120/126 attempts (95.2 %) and, where possible, the en bloc and R0 resection rates were 95.8 % (115/120) and 76.7 % (92/120), respectively. Thirty-three resections (26.2 %) were for very low risk tumors, so considered curative, and 38 (30.2 %) were for low risk lesions. Noncurative R0 resections were for lesions with lymphatic or vascular invasion (LVI; n = 8), or significant budding (n = 9), and LVI + budding combination (n = 4). CONCLUSION: ESD is feasible and safe for colorectal lesions with an FDIP ≤ 15 mm. It was curative in 26.6 % of patients and could be a valid option for a further 30.6 % of patients with low risk T1 cancers, especially for frail patients with co-morbidities.