A Study of the Drug 131I-Omburtamab in Patients with Desmoplastic Small Round Cell Tumors

Inclusion Criteria

• Have the diagnosis of DSRCT confirmed at Memorial Sloan Kettering Cancer Center (MSKCC)
• Age > 1 and able to cooperate with radiation safety restrictions during therapy period
• Must have an autologous hematopoietic stem cell product cryopreserved and available for re-infusion after 131I-omburtamab treatment with a minimum dose of 2 x 10^6 CD34+ cells/kg
• Prior to intraperitoneal catheter placement * At least 1 weeks must have elapsed since prior chemotherapy * At least 2 weeks must have elapsed since biologic therapy * Toxicities of prior therapy must have resolved to grade 1 or less or to the patient’s baseline
• At the completion of surgery, patients must fulfill all the additional following criteria: * Have undergone GTR of radiographically evident and visible/palpable disease, as per surgeon’s impression/report * Have no definitive radiological evidence of active disease in liver or outside the abdomen/pelvis OR have had GTR of this disease at the time of catheter placement

Exclusion Criteria

• Prior abdomen or pelvis radiation therapy
• Prior progression of disease
• Prior hypothermic intraperitoneal chemotherapy (HIPEC)
• Cardiac, pulmonary, and neurologic toxicities are greater grade 1 (per National Cancer Institute [NCI] Common Terminology Criteria for Adverse Events [CTCAE] version 5)
• Renal, gastrointestinal, and hepatic toxicities are greater than grade 2 (per NCI CTCAE version 5)
• Clinically suspected or surgically demonstrated dense intraperitoneal adhesions preventing adequate intraperitoneal distribution of drug
• History of allergy to mouse proteins
• Active serious infections not controlled by antibiotics
• Grade 4 hypersensitivity reaction to radiolabeled iodine
• Pregnant women and women who are breast feeding; negative pregnancy test is required for all biologic females with child-bearing potential within two weeks of administration; appropriate contraception must be used during the study period and for 12 months following therapy