In this report, we demonstrate echocardiographic findings in a case of renal cell carcinoma with the tumor thrombus extending into the right atrium. A 26-year-old female who complained of dull lumbar pain, progression of anorexia, weight loss and breathlessness during effort was found to have a left renal cell carcmoma. The inferior venacavogram and CT scan showed extension of tumor thrombus from the left renal vein through the inferior vena cava into the right atrium. But we could not define its intracardiac position and motion.
By two-dimensional echocardiography, it was detected that the abnormal spotty mass echoes filled the entire right atrial cavity and prolapsed into the right ventricle across the tip of the tricuspid valve during diastole. The spotty echoes were considered to show that tumor mass was non-homogeneous. The boundaries between the tumor thrombus and the right atrial wall was clearly defined. By M-mode echocardiography, the tumor thrombus was detected as stratified echoes composed of various ehco intensity.
The echocardiographic findings were confirmed later by operation. The tumor consisted of the mass of renal cell carcinoma and thrombus, but it did not involve the cardiac wall.
Extension of renal cell carcinoma into the right atrium has been reported to be very rare. This is the first
report which demonstrated two-dimensional echocardiographic findings of intraatrial tumor thrombus.