An Investigational Scan (68Ga-DOTATATE PET/CT) in Diagnosing Pediatric Metastatic Neuroendocrine Tumors

This trial studies how well an investigational scan called 68Ga-DOTATATE PET/CT works in diagnosing pediatric patients with neuroendocrine tumors that have spread to other places in the body (metastatic). A neuroendocrine tumor is an abnormal growth of neuroendocrine cells, which are cells resembling nerve cells and hormone-producing cells. 68Ga-DOTATATE is a radioactive substance called a radiotracer that when used with PET/CT scans, may work better than standard of care MIBG scans in diagnosing pediatric metastatic neuroendocrine tumors and targeting them with radiation therapy.

PRIMARY OBJECTIVE: I. To estimate the difference in radiation therapy (RT) target volume definition between gallium Ga 68-DOTATATE (68Ga-DOTATATE) PET/CT and iobenguane (metaiodobenzylguanidine \[MIBG\]). SECONDARY OBJECTIVES: I. To estimate the difference in metastatic tumor burden as detected by 68Ga-DOTATATE PET/CT and MIBG. II. To estimate the difference in metabolic activity between tumors diagnosed on 68Ga-DOTATATE PET/CT and MIBG. III. To evaluate patterns of failure after RT in association with 68Ga-DOTATATE PET/CT and MIBG. OUTLINE: Patients are assigned to 1 of 2 cohorts. COHORT A: Patients with newly diagnosed high-risk neuroendocrine cancer receive 68Ga-DOTATATE intravenously (IV) and undergo PET/CT over 20-30 minutes at diagnosis (before any treatment) and at the time of radiation treatment planning. COHORT B: Patients with previously diagnosed high-risk neuroendocrine cancer receive 68Ga-DOTATATE IV and undergo PET/CT over 20-30 minutes at the time of radiation treatment planning. After completion of study, patients are followed up per standard of care for up to 2 years.