The purpose of this study is to see if preoperative administration of Sorafenib reduces the size of the primary kidney tumour in patients with metastatic disease undergoing cytoreductive surgery.

The study will also assess the safety of preoperative Sorafenib.

The study drug, Sorafenib, will be given to patients preoperatively for 12 weeks. After a 1 week washout period the patient will then have their nephrectomy (kidney removed). Approximately 6 weeks following their nephrectomy, patients will resume on study drug until disease progression.

This is a single centre, non-randomized, open label one arm pilot study of Sorafenib 400 mg twice daily given for 12 weeks preoperatively in patients with advanced metastatic kidney cancer scheduled for cytoreductive surgery. Patients will be fully staged for disease progression with Brain MRI, CT, whole body Bone Scans, Kidney ultrasound and biopsy. Additionally, patients' cardiac status will be evaluated pre-enrolment with an ECG and MUGA Scan. Once enrolled into the study, patients will have clinic visits on weeks 2, 8 and 12 for monitoring visits with vital signs and adverse event recording plus blood evaluations for hematology and chemistry. Patients will be called on weeks 3,5,6,7,9,10 and 11 to determine any changes in health status. Surgery will occur at week 13, after a one week washout from study drug. Patients will resume on study drug 6 weeks post operatively (or later, if wound is not completely healed). Patients will continue on study drug and will be monitored every 4 weeks until disease progression, as determined by bone imaging and CT.

Inclusion Criteria:

• Biopsy proven RCC with a component of clear cell type histology

• Patients must have confirmed metastatic disease

• Candidate for cytoreductive nephrectomy

• Adequate organ function as defined by:

  • AST or ALT less than or equal to 2.5 times the upper limit of normal
  • Bilirubin less than or equal to 1.5 times the upper limit of normal
  • Absolute neutrophil count (ANC) greater than or equal to 1500/mL
  • Platelets greater than or equal to 100,000/mL
  • Hemoglobin greater than or equal to 9.0 g/dL
  • Serum calcium less than or equal to 12.0 mg/dL
  • Serum creatinine less than or equal to 1.5 x CL-ULN

• Male or female, 18 years of age or older

• Women of childbearing potential must NOT be pregnant (as confirmed by a negative pregnancy test)

• ECOG performance status 0 or 1 (see appendix 1 for ECOG performance status)

• Signed informed consent form indicating that the patient or acceptable representative has been informed of all parts of the trial prior to enrollment

• Willingness and ability to comply with study procedures

Exclusion Criteria:

• Presence of brain metastases during screening period
• Known hypersensitivity to Sorafenib
• Women who are breast-feeding
• Severe psychiatric or medical illness that may interfere with compliance with the study protocol or follow-up as deemed by the investigator
• History of cardiac disease: congestive heart failure >NYHA class 2; active CAD (MI more than 6 mo prior to study entry is allowed); cardiac arrhythmias requiring anti-arrhythmic therapy (beta blockers or digoxin are permitted) or uncontrolled hypertension.
• HIV-positive patients