Inclusion Criteria:

- At least 18 years old and capable of giving informed consent.

- Patient has radiological evidence of RCC consisting of: CT scan with stage T2, T3,
T3a, T4, or any stage T with N1/2 and/or metastatic disease.

- Patient is already having a nephrectomy.

- Adequate cardiac function as assessed by electrocardiogram (ECG).

- Patient is will to have a kidney biopsy at baseline/screening.

- Patient has scored a 0 or 1 on the ECOG.

- Patient is negative for HIV, Hepatitis B, Hepatitis C

- If patient is a woman of child-bearing potential, they have to have a negative
pregnancy test.

Exclusion Criteria:

- Patient has stage T1 disease without metastases.

- Patient has abnormal laboratory values at screening within the following ranges:

- Absolute neutrophil count ≤1.5 x 10(9)/L; Platelet count ≤ 100 x 10(9)/L

- Leukocyte count ≤ 3 x 10(9)/L; Hemoglobin ≤ 80 g/L

- Serum creatinine ≥ 2.0 x the upper normal limit (UNL)

- Total bilirubin ≤ 1.5 x UNL; AST and ALT ≤ 3.0 x UNL

- Fasting serum cholesterol ≤ 9.0 mmol/L

- Fasting serum triglycerides ≤ 5.0 mmol/L

- Patients with a known hyper-sensitivity to Temsirolimus.

- Other currently active malignancies.

- Currently taking any medications known to interfere with the metabolism of
Temsirolimus.

- Patients receiving anticoagulation with warfarin.

- Patients with a history of pulmonary hypertension or interstitial lung disease.

- Unstable angina as judged by the primary investigator, or any recent MI in the last
180 days.