DISEASE CHARACTERISTICS:

• Diagnosis of renal cell carcinoma (RCC) as confirmed by either of the following:

  • Radiographic documentation by MRI or CT scan
  • Histological evidence of primary RCC

• Stage II-IV disease, as defined by any of the following:

  • T > 7 cm
  • Renal vein involvement
  • Local invasion
  • Evidence of lymph node involvement
  • Distant metastatic disease

• Deemed suitable for nephrectomy by a urologist

  • No requirement for surgery earlier than 4 weeks from study entry

• No known brain metastasis

  • Patients with neurological symptoms must undergo a CT scan or brain MRI to exclude brain metastasis

PATIENT CHARACTERISTICS:

• ECOG performance status 0-1
• Hemoglobin ≥ 9.0 g/dL
• ANC ≥ 1,500/mm³
• Platelet count ≥ 100,000/mm³
• Bilirubin ≤ 1.5 times upper limit of normal (ULN)
• ALT and AST ≤ 2.5 times ULN (≤ 5 times ULN for patients with liver involvement)
• Creatinine ≤ 2.5 times ULN or glomerular filtration rate ≥ 50 mL/min

• INR ≤ 1.5 AND PTT normal

  • Stable INR required at baseline for patients on warfarin
• Not pregnant or nursing
• Negative pregnancy test
• Fertile women must use effective contraception
• Fertile men must use effective contraception during and for ≥ 2 months after the last dose of sorafenib tosylate
• No other active primary malignancy except skin cancer
• No active coronary artery disease

• No active bleeding diathesis

  • Closely monitored therapeutic anticoagulation allowed

• No cardiac disease, including any of the following:

  • New York Heart Association class III-IV congestive heart failure
  • Unstable angina (i.e., anginal symptoms at rest) or new onset angina (i.e., beginning within the past 3 months)
  • Myocardial infarction within the past 6 months
• No cardiac ventricular arrhythmias requiring anti-arrhythmic therapy
• No uncontrolled hypertension, defined as systolic blood pressure (BP) > 150 mm Hg or diastolic BP > 90 mm Hg, despite optimal medical management
• No known HIV infection or chronic hepatitis B or C
• No active, clinically serious infection > grade 2
• No thrombolic or embolic events, such as a cerebrovascular accident or transient ischemic attacks, within the past 6 months
• No pulmonary hemorrhage or bleeding event ≥ grade 2 within the past 4 weeks (≥ grade 3 for any nonpulmonary hemorrhage or bleeding event)
• No serious nonhealing wound, ulcer, or bone fracture
• No significant traumatic injury within the past 4 weeks
• No known or suspected allergy to sorafenib tosylate or any agent given in the course of this study
• No condition that impairs the patient's ability to swallow whole pills
• No malabsorption problem

PRIOR CONCURRENT THERAPY:

• No major surgery or open biopsy within the past 4 weeks
• Concurrent anticoagulation therapy (e.g., warfarin or heparin) allowed
• No other concurrent investigational or commercial agents or therapies for RCC
• No concurrent Hypericum perforatum (St. John's wort) or rifampin