Safety and Feasibility of Intraoperative Visualization With Cytalux in Children

1. Patients 6-17 years of age at the time of study enrollment 2. Willingness of research participant or legal guardian/representative to give written informed consent 3. Willingness of patients (subjects) age 12-17 to provide written adolescent assent 4. Patient weight greater than or equal to 20 kg 5. Histologically confirmed diagnosis of osteosarcoma, synovial sarcoma, hepatoblastoma, rhabdomyosarcoma, Ewing sarcoma, Wilms tumor or other non-rhabdomyosarcoma soft tissue sarcoma 6. Imaging findings highly suspicious for pulmonary metastatic disease based on CT, PET-CT or other imaging and warranting pulmonary surgery based on the judgment of the treating team. At least one nodule ≥4mm measured by preoperative imaging. 7. Female (assigned female at birth) participant is not pregnant and agrees to an acceptable form of contraception from the time of consent through 30 days after study intervention. Confirmed abstinence is an acceptable form of contraception. 8. Female (assigned female at birth) participant must agree to not donate ova from time of consent until 30 days after study intervention 9. Male (assigned male at birth) participant must agree to not donate sperm from time of consent until 30 days after study intervention.

1. Any medical condition that in the opinion of the investigators could potentially jeopardize the safety of the subject 2. History of anaphylactic reactions to products containing indocyanine green for near infrared imaging. Subjects with a medical history of 'idiopathic anaphylaxis' will also be excluded. 3. History of allergy to any of the components of CYTALUX™ (PAFOLACIANINE) INJECTION 4. Presence of any psychological, familial, sociological condition or geographical challenges potentially hampering compliance with the study protocol or follow-up schedule 5. Impaired renal function defined as eGFR\< 50 mL/min/1.73m2 6. Impaired liver function defined as values \> 3x the upper limit of normal (ULN) for alanine aminotransferase (ALT) or aspartate aminotransferase (AST), alkaline phosphatase (ALP), or \>2x ULN for total bilirubin except in subjects with Gilbert's syndrome. 7. Patient unable or unwilling to discontinue folate, folic acid, or folate-containing supplements 48 hours before study drug administration 8. History of drug-related serious adverse event with prior Cytalux administration will be an exclusion for re-enrollment for contralateral surgery (see section 5.7). 9. Participants will be excluded if their 12th or 18th birthday would occur during study participation 10. Male sex at birth and commitment to acceptable form of contraception from time of consent through 30 days after study intervention with confirmed abstinence as an acceptable form of contraception as an inclusion criterion.