Ferumoxytol - Iron Oxide Nanoparticle Magnetic Resonance Dynamic Contrast Enhanced MRI

Study Scans: If you are found to be eligible to take part in this study, you will have 2 study MRIs. These scans will be performed at the Center for Advanced Biomedical Imaging (CABI), in the South Campus Research Building at MD Anderson. On Day 1, you will have 2 standard MRIs, as part of your standard of care. About an hour after these 2 scans, you will receive ferumoxytol by vein. Right after that, you will have your first study MRI. The study MRI will be performed in the same way that a standard MRI is performed. On Day 2, about 24 and 72 hours after you receive ferumoxytol, you will have a second study MRI. Additional Tests: On Days 1 and 3, as well as 4 weeks after the first study MRI: * You will have a physical exam. * Blood (about 2 teaspoons) will be drawn for routine tests and/or to check your iron level. On Day 2: * You will have a physical exam. * If you have not had one in the last month, you will have a PET-CT scan to check the status of the disease. Length of Study: You will be on study for about 4 weeks. You will be taken off study if you have intolerable side effects or you are unable to have the scans for any reason. This is an investigational study. Ferumoxytol is commercially available and FDA-approved for the treatment of iron deficiency anemia. Up to 20 patients will take part in this study. All will be enrolled at MD Anderson.