Sorafenib in Treating Patients With Locally Advanced or Metastatic Kidney Cancer

RATIONALE: Sorafenib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. Giving sorafenib before surgery may make the tumor smaller and reduce the amount of normal tissue that needs to be removed. PURPOSE: This clinical trial is studying how well sorafenib works in treating patients with locally advanced or metastatic kidney cancer.

OBJECTIVES: Primary * To demonstrate the feasibility and safety of sorafenib tosylate when given prior to nephrectomy or metastasectomy. * To evaluate the ability of diffusion-weighted magnetic resonance imaging (DW-MRI) to detect early and ongoing microstructural changes in primary and metastatic renal cell carcinoma lesions during neoadjuvant therapy with sorafenib tosylate. * To correlate early and ongoing microstructural changes in primary and metastatic renal cell carcinoma lesions with pathologic and clinical findings at the time of nephrectomy or metastasectomy. * To evaluate the ability of changes in DW-MRI to predict subsequent favorable response to treatment (complete or partial response or stable disease) after 4 weeks of therapy. OUTLINE: Patients receive oral sorafenib tosylate twice daily on days 1-28. Patients then undergo a nephrectomy or metastasectomy in week 5. Patients with residual metastatic disease may continue sorafenib tosylate twice daily and undergo a diffusion-weighted MRI (DW-MRI) every 8 weeks in the absence of disease progression or unacceptable toxicity. Patients undergo a DW-MRI of the abdomen and pelvis at baseline and prior to week 5 to evaluate microstructure tumor changes and to allow for prediction of sorafenib tosylate benefit. DW-MRI results are correlated with surgical and pathologic findings obtained at week 5. Resected tumor tissue are analyzed for vascular density and to distinguish apoptotic cell death from necrotic cell death via immunohistochemistry and to measure apoptotic cell death via TUNEL assay. After completion of study treatment, patients are followed every 3 months for 2 years.