RecruitingEarly Phase 1Drug trialIndocyanine Green (ICG) Guided Sentinel Lymph Node Mapping for Pediatric Visceral Solid TumorsThe purpose of the study is to find out the usefulness and safety of a dye called Indocyanine Green (ICG for short). This dye will be used to help the surgeon find lymph nodes draining solid tumors inside the abdomen that need to be removed. This may also help the surgeon to find if the cancer has moved to other lymph nodes outside of the known area. Primary Objectives * To determine the percentage of patients in whom Indocyanine Green (ICG)-guided sentinel lymph node (SLN) mapping was successful at the time of retroperitoneal lymph node dissection for staging of visceral solid tumors. * To determine the percentage of patients with grade 3 or higher adverse events related to ICG use.