Stereotactic Body Radiotherapy (SBRT) and Sorafenib in Patients With Metastatic, Recurrent, or Unresectable Renal Cell Cancer (RCC)

Inclusion Criteria:

* Age \> 18 years old
* Zubrod Performance Status 0 or 1
* Adequate bone marrow, liver and renal function as assessed by the following:

  * Hemoglobin \> 9.0 g/dl
  * Absolute neutrophil count (ANC) \> 1,500/mm3
  * Platelet count \> 100,000/mm3
  * Total bilirubin \< 1.5 times institutional upper limit of normal (ULN)
  * Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) \< 2.5 times the institutional ULN
  * Creatinine \< 1.5 times institutional ULN
* Histologically or cytologically confirmed renal cell carcinoma, which is metastatic, unresectable or recurrent.
* Life expectancy \> 6 months
* Local recurrence or progression of primary lesion or progression, or symptomatic progression in extra-cranial, extra-pulmonary metastases while on sorafenib
* Measurable disease
* Bone metastases must have a tissue component measurable by imaging.
* No untreated brain metastases
* Resolution of pre-existing toxicity from prior therapy excluding alopecia and taste alteration.
* Willingness and ability to comply with continuing sorafenib, visits, treatment plans, laboratory tests and study procedures.
* All treated lesions must comply with SBRT dose constraints
* More than 28 days since any prior systemic or local therapy for this cancer, including investigational agents and surgical procedures exclusive of sorafenib
* Women of childbearing potential and men must agree to use adequate contraception (barrier method of birth control)
* Women of childbearing potential must have a negative serum pregnancy test performed within 7 days prior to the start of treatment.
* Ability to understand and the willingness to sign a written informed consent.
* Prothrombin time(PT) and partial thromboplastin time (PTT) within normal limits.

Exclusion Criteria:

* Lesion in remaining (solo) kidney
* Contraindications to radiotherapy or prior radiotherapy overlapping current site(s) of disease.
* Cardiac disease: Congestive heart failure. Patients must not have unstable angina (anginal symptoms at rest) or new onset angina (began within the last 3 months) or myocardial infarction within the past 6 months.
* Cardiac ventricular arrhythmias requiring anti-arrhythmic therapy.
* Uncontrolled hypertension defined as systolic blood pressure \> 150 mmHg or diastolic pressure \> 90 mmHg, despite optimal medical management.
* Known human immunodeficiency virus (HIV) infection or chronic Hepatitis B or C.
* Active clinically serious infection
* Thrombolic or embolic events such as a cerebrovascular accident including transient ischemic attacks within the past 6 months.
* Pulmonary hemorrhage/bleeding event within 4 weeks of first dose of study drug.
* Any other hemorrhage/bleeding event within 4 weeks of first dose of study drug.
* Serious non-healing wound, ulcer, or bone fracture.
* Evidence or history of bleeding problems
* Major surgery, open biopsy or significant traumatic injury within 4 weeks of first study drug.
* Use of St. John's Wort or rifampin (rifampicin).
* Known or suspected allergy to sorafenib or any agent given in the course of this trial.
* Any condition that impairs patient's ability to swallow whole pills.
* Any malabsorption problem.