Carfilzomib in Refractory Renal Cell Carcinoma (RCC)

Study Groups and Study Drug Administration: If you are found to be eligible to take part in this study, you will receive carfilzomib 2 days a week for the first 3 weeks of each 4-week study cycle (Days 1, 2, 8, 9, 15, and 16 of each cycle). Each dose is given by vein over about 30 minutes. Before you receive the study drug, you will be given dexamethasone to help decrease the risk of side effects during the first cycle. You may ask the study staff for information about how the drugs are given and their risks. During Cycle 1, you will receive extra fluid (saline) by vein before each dose of study drug. This is part of standard clinical care. This will also be done during Cycle 2, if the study doctor thinks it is needed. You will remain in the clinic for an extra hour after receiving each dose during Cycle 1 and after the first dose of Cycle 2, to receive additional fluids by vein. If you have any side effects from the drug, tell the study doctor right away. The study doctor may then lower the dose or keep the dose level the same. Each study cycle is 4 weeks. Study Visits: Weeks 1, 2, and 3 of each cycle: * Your vital signs and weight will be measured. * Blood (about 3 teaspoons) will be drawn for routine tests Every 4 weeks (+/-4 days): * Your medical history will be recorded. * You will have a physical exam, including measurement of your vital signs and weight. * You will be asked about any drugs or treatments you may be receiving and any side effects that you have had. * Your performance status will be recorded. * Blood (about 3 teaspoons) will be drawn for routine tests and to check your blood sugar level and your pancreatic function, if the study doctor thinks it is needed. You will be asked to fast (not eat, and drink only water) for at least 8 hours before this blood draw. Every 8 weeks (+/-7 days): * You will have an x-ray of chest, CT scan of the chest and abdomen, and MRI scan of the brain to check the status of the disease. If the doctor thinks it is needed, you will also have a bone scan. * If you can become pregnant, you will have a blood (about 2 teaspoons) pregnancy test. Length of Study: You may continue taking the study drug for as long as the doctor thinks it is in your best interest. You will no longer be able to take the study drug if the disease gets worse, intolerable side effects occur, or you are not able to follow study directions. End-of-Treatment Visit: About 30 days after your last dose of the study drug: * You will have a physical exam, including measurement of your vital signs and weight. * You will be asked about any drugs or treatments you may be receiving and any side effects that you have had. * Blood (about 3 teaspoons) will be drawn for routine and blood sugar tests. * You will have an x-ray, CT scan, and MRI scan to check the status of the disease. Long-Term Follow-up: After you stop taking the study drug, the study staff will check your health status every 6 months for the rest of your life. The study staff will collect this information by either checking your medical record, emailing you, or calling you on the telephone. Each call should only last about 5 minutes. This is an investigational study. Carfilzomib is FDA approved and commercially available in treatment of multiple myeloma. The use of carfilzomib in kidney cancer is investigational. Up to 40 patients will take part in this study. All will be enrolled at MD Anderson.