P1.174. Fluorescence Guided Lymph Node Dissection Using Indocyanine Green During Minimally Invasive Esophageal Cancer Surgery [IGLO] - Pilot-Study

Topic Esophageal Cancer: Surgical Treatment of Esophageal Cancer – technique Background Standardization of lymphadenectomy extent in esophageal cancer surgery is complex due to the heterogenous lymphatic drainage patterns. Fluorescence guided lymph node dissection using indocyanine green (ICG) potentially enables selective resection of tumor-draining lymph nodes, which could optimize the balance between individualized oncologic radicality and surgical risk. Methods This ongoing single-center, prospective pilot study investigates ICG-enhanced lymph node fluorescence during minimally invasive esophagectomy for esophageal carcinoma (cT1–4aN0–3M0), after completion of neoadjuvant chemo(radio)therapy. Four peritumoral ICG-injections (four times 0.5ml of 0.05 mg/ml) are administered endoscopically after intubation. Two-field lymphadenectomy is performed according to the TIGER study protocol. Lymph nodes are stratified based on presence of intraoperative ICG signal for histopathological assessment. The primary outcome is succession rate of lymph node visualization using ICG. Secondary outcomes include adverse events, and histopathological correlation between presence of ICG signal and lymph node metastases. Results Twenty of the 40 planned patients were enrolled up to January 2026. No study-related adverse events occurred. Pathological N+ stage was observed in 8/20 patients (40%). In total, 648 lymph nodes were analyzed (median lymph node yield: 31 [IQR 27–43]), containing metastases in 28. ICG signal was present in 146 lymph nodes, distributed over 18/20 patients (88%). Histopathological evaluation demonstrated a high negative-predictive value (94.7%) for ICG-negative lymph nodes, with a specificity of 88.4%, although sensitivity remained low (25%). Conclusion ICG-guided lymph node mapping during minimally invasive esophagectomy is both safe and feasible, demonstrating a promising negative predictive value for precluding metastatic disease. The current pilot study will support transition towards the phase III trial. Final analyses are expected in May 2026.