Renal Cell Carcinoma (RCC) is the most common type of kidney cancer. The usual treatment for this type of cancer is surgery. Considering the most common patients are an average age of 65 and some are not suitable candiates for surgery, there is great interest in non-surgical alternatives for kidney cancer treatments. This study will investigate the use of Stereotactic Ablative Radiosurgery (SABR) for renal tumors. SABR is a non-invasive alternative, which involves delivery of high doses of radiation to the target, while minimizing the risk of injury to the surrounding organs. Patients will be seen before and end of treatmetn and will be followed at 4 month intervals for up to 2 years. During the follow ups, patients will be asked to complete a quality of life questionnaire and will have standard of care imaging.

Inclusion Criteria:

• Solid Kidney Mass (primary RCC or metastasis) amenable to SABR ≤6cm
• Histological or radiological diagnosis of renal tumor
• Inoperable: High risk for surgery or declined surgery
• ECOG performance status of 0-3

Exclusion Criteria:

• ≥5 active metastases
• Systemic therapy (except endocrine therapy) within 60 days prior to SABR
• Prior abdominal radiotherapy with fields overlap resulting in excessive doses to the involved kidney
• Patients with end stage renal failure > 4(KDOQI guidelines)
• Familial Syndrome: Von Hippel-Lindau disease, Polycystic Kidney Disease, Hereditary Papillary RCC or Tuber Sclerosis