Quantitative Imaging Biomarkers of Treatment Response in Osteosarcoma and Ewing Sarcoma

Inclusion Criteria: * Subjects must be 13 years of age or older. * Subjects (or their parent or legal guardian) must have signed Internal Review Board (IRB)-approved assent/informed consent documentation. * Subjects must have histologically proven osteogenic sarcoma, malignant fibrous histiocytoma (MFH), or Ewing sarcoma. * Subjects must be planned for resection (this includes localized resectable disease or patients with metastatic disease with planned palliative resection) and scheduled to begin neoadjuvant chemotherapy Exclusion Criteria: * Subjects who are under 13 years of age. * Subjects who have any type of bioimplant activated by mechanical, electronic, or magnetic means (e.g., cochlear implants, pacemakers, neurostimulators, biostimulators, electronic infusion pumps, etc), because such devices may be displaced or malfunction. * Subjects who have any type of ferromagnetic bioimplant that could potentially be displaced. * Subjects who have cerebral aneurysm clips. * Subjects who may have shrapnel imbedded in their bodies (such as from war wounds), metal workers and machinists (potential for metallic fragments in or near the eyes). * Subjects with inadequate renal function (creatinine ≥1.5 times upper limit of normal) or acute or chronic renal insufficiency (estimated glomerular filtration rate \<30 mL/min). * Subjects who are pregnant or breast feeding, because the effects of high field MRI on fetuses are not yet known. Urine pregnancy test/or serum human chorionic …