Abstract
Symptoms of renal cell carcinoma include flank pain, a palpable mass, and hematuria. At sonographhy, the tumor is frequently a contour-deforming renal mass that is less echogenic than normal renal parenchyma. Renal cell carcinoma has a propensity to invade the renal vein and grow toward the right atrium along the inferior vena cava. It is essential to define the extent of tumor involvement by evaluating the renal vein, inferior vena cava, and right atrium. Observation of a distended thrombus-filled renal vein in the setting of a: hypoechoic renal mass should prompt a search for retroperitoneal lymphadenopathy and other signs of distant metastatic disease. Renal cell carcinoma most commonly metastasizes to the lung, bone, lymph nodes, liver, adrenal glands, brain, and contralateral kidney.