The purpose of this study is to assess magnetic resonance imaging (MRI) as a tool to track tumor growth for renal cell carcinoma while the participant is receiving clinical treatment therapy with sunitinib or pazopanib. An MRI is a sophisticated type of scan that uses powerful magnets to make clearer images or to focus on detailed medical information in the participants abdomen and pelvis. This imaging done for this study will use the ASL MRI technique that allows us to see blood flow changes which possibly may indicated tumor growth.

• MRI's will be performed at specific time points during the participants treatment for renal cell carcinoma with the drug sunitinib or pazopanib. These ASL MRI's will be performed at baseline, 2 weeks upon initiation of therapy with sunitinib/pazopanib, after cycle 2 and/or cycle 4 of therapy, and at the end of therapy.
• The MRI tests for all participants will be done at Beth Israel Deaconess Medical Center.

Inclusion Criteria:

• Patients diagnosed with metastatic renal cell carcinoma and who will initiate sunitinib or pazopanib
• Enrolled on protocol 06-105, "Collection of specimens and clinical data from patients with renal cell carcinoma treated with targeted therapies," or receiving Pazopanib as part of routine clinical care.
• Found to have tumors that are 2.5cm or greater as determined by CT imaging
• Candidate lesions for ASL MRI should be 2.5cm or greater. Order of preference of lesion location will be as follows: abdominal lesions, bone lesions and chest lesions

Exclusion Criteria:

• Contraindication to MRI

No plan to share IPD