Indocyanine Green Fluorescence for Intraoperative Tumor Identification During Resection of Pediatric and Adolescent Intra-Abdominal Malignancy: A Prospective Multi-Institutional Observational Study

Background: Real-time intraoperative discrimination of malignant tissue during pediatric solid-tumor resection is limited, constraining margin optimization; the use of indocyanine green (ICG) fluorescence in this population remains incompletely defined. Study Design: Prospective, observational, multi-institutional study (2019 to 2023) of pediatric, adolescent, and young adult patients undergoing resection of intra-abdominal solid malignancies after preoperative ICG administration. The primary endpoint was diagnostic accuracy of ICG fluorescence for tumor-containing specimens; secondary endpoints included association with margin status and surgeon-perceived intraoperative benefit. Results: Forty-three operations in 42 patients yielded 55 specimens, of which 47 (85%) were malignant. Diagnostic performance was highest in hepatic tumors (sensitivity 83%, positive predictive value 83%) and lower in adrenal and heterogeneous tumor types. ICG avidity was not associated with improved negative margin rates (86% vs 75%, p = 0.47). Surgeons reported intraoperative benefit in 67% of cases, most commonly improved visualization. No ICG-related adverse events occurred. Conclusions: ICG fluorescence provides reliable tumor identification in hepatic malignancies but does not correlate with margin-negative resection, indicating limited use for margin guidance. These data support tumor-specific application and further investigation of optimized fluorescence strategies, including dosing, timing,