- Compare non-inferior diagnostic performance of whole-body MRI (i.e., combination of turbo short-tau inversion-recovery (STIR) and out-of-phase imaging) vs conventional imaging (i.e., the combination of chest CT scan, scintigraphy [bone, gallium, meta-iodobenzylguanidine (MIBG), or optional fludeoxyglucose F 18 positron emission tomography (FDG-PET)] and abdominal/pelvic CT scan/MRI as indicated) for detecting distant metastases for use in staging common tumors in pediatric patients.