The aim of this study is to determine the utility of renal ultrasonography (US) in the detection of abdominal recurrences after definitive therapy for renal cell carcinoma (RCC) and compare the detection rate to that of cross-sectional imaging.

Inclusion Criteria:

• Patients must be 18 year of age or older.
• Patients having undergone radical or partial nephrectomy for the indication of renal cell carcinoma.
• Most recent imaging study must have been either computed tomography (CT) or magnetic resonance imaging (MRI).

Exclusion Criteria:

• Patients with pT4 disease (tumor invades beyond the Gerota fascia: including contiguous extension into the ipsilateral adrenal gland).
• Patients with metastatic disease prior to time of surgery requiring systemic treatment.
• Patients with another active cancer diagnosis requiring systemic treatment.
• Patients with contrast allergies.
• Patients with baseline chronic kidney disease (GFR < 45 ml/min/1.73 m2).

The sonographer for the additional ultrasound will be blinded as will be the blinded radiology who will compare the US to the most recent negative CT/MRI to determine if recurrence is visualized by US