Sorafenib in Treating Patients With Kidney Cancer That Has Spread to the Brain

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed renal cell carcinoma metastatic to the brain Measurable disease in the brain Meets 1 of the following criteria: No prior brain-specific therapy AND no CNS symptoms referable to the brain lesion(s) (with or without concurrent steroid therapy) CNS symptoms referable to the brain lesion(s) AND received primary therapy for the brain lesion(s) PATIENT CHARACTERISTICS: Blood pressure < 140/90 mm Hg on 2 separate occasions, taken at least 24 hours apart, within the past 6 weeks (patients on stable anti-hypertensive regimens allowed) ECOG performance status (PS) 0-2 OR Karnofsky PS 60-100% Bilirubin < 1.5 times upper limit of normal (ULN) ALT/AST < 2.5 times ULN Estimated glomerular filtration rate > 30 mL/min Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception Able to swallow pills or comply with an oral treatment regimen No history of a bleeding diathesis or requirement for full-dose anticoagulation No history of allergic reactions attributed to compounds of similar chemical or biologic composition to sorafenib No clinical or radiologic evidence of bowel obstruction or perforation No other uncontrolled intercurrent illness including, but not limited to, any of the following: Ongoing or active infection Symptomatic congestive heart failure Unstable angina pectoris Cardiac arrhythmia Psychiatric illness or social situation that would limit compliance with study requirements PRIOR CONCURRENT THERAPY: More than 4 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin C) and recovered More than 4 weeks since prior radiotherapy to sites outside of the brain and recovered More than 8 weeks since prior standard external-beam radiotherapy to the brain unless there is evidence of in-brain progression No prior complete surgical resection or radiosurgery of all known brain metastases unless there is evidence of in-brain progression No prior sorafenib, sunitinib malate, bevacizumab, or any other agent targeting the platelet-derived growth factor receptor (PDGFR) or vascular endothelial growth factor receptor (VEGFR) kinase cascade No other concurrent investigational agents No concurrent enzyme-inducing anti-seizure medications, including phenytoin, phenobarbital, carbamazepine, or primidone Concurrent non-enzyme-inducing anti-seizure medications allowed No concurrent combination antiretroviral therapy for HIV-positive patients No concurrent hematopoietic growth factors except erythropoietin No concurrent ketoconazole, itraconazole, or ritonavir No concurrent grapefruit juice No concurrent Hypericum perforatum (St. John's wort) No concurrent chemotherapy No concurrent hormonal therapy except steroids for adrenal failure and/or control of CNS edema or hormones for non-disease related conditions (e.g., insulin for diabetes) No concurrent palliative radiotherapy No other concurrent anticancer therapy Concurrent bisphosphonates allowed