COmpletion Sentinel Node resection with or without minimally invAsive and endoscopic cooperative surgery following non-cuRative Endoscopic Submucosal Dissection (Co-SNARE trial): protocol for a phase 1 trial (Preprint)

BACKGROUND After non-curative resection for early gastric cancer (EGC) with endoscopic submucosal dissection (ESD), gastrectomy with lymphadenectomy is generally recommended. However, most patients are found to have no residual cancer in the stomach or regional lymph nodes, while surgery carries a considerable risk of postoperative complications. In Western settings, patients with EGC are often elderly and have concomitant comorbidities. OBJECTIVE In this study, we aim to assess the feasibility and safety of indocyanine-green (ICG) - guided lymphadenectomy with or without laparoscopic and endoscopic cooperative surgery (LECS) following non-curative ESD for EGC. METHODS A single-center phase 1 prospective trial. Patients with EGC treated with ESD within the expanded criteria will be considered for inclusion, provided the resection was non-curative (eCuraC2). For patients with radically resected EGC, ICG-guided lymphadenectomy alone will be performed. In those with a non-radically resected EGC, ICG-guided lymphadenectomy and LECS will be performed. The primary objective is to evaluate the safety of the procedure, defined as Clavien-Dindo grade III or more. The secondary endpoints include other complications, operation time, number of positive lymph nodes, short-term mortality, and health-related quality of life. RESULTS As of January 9th, 2026, no patients have yet been recruited to the trial. CONCLUSIONS ICG-guided lymphadenectomy with or without LECS is an appealing and potentially promising treatment strategy following non-curative ESD for EGC. To the best of our knowledge, no previous studies from the Western world have been conducted on this subject. CLINICALTRIAL ClinicalTrials.gov identifier: NCT07295002 Registered December 18th, 2025. URL: https://clinicaltrials.gov/study/NCT07295002?term=NCT07295002&rank=1