Simultaneous occurrence of a large asymptomatic prolapsing left atrial myxoma with a cutaneous squamous cell carcinoma.

Synchronous myxoma of the heart and other malignancies are extremely rare. We report a case of a 64-year-old man who had a large left atrial myxoma that obstructed the mitral valve, as well as an unrelated, coexistent cutaneous squamous cell carcinoma in the sacral area. During the preoperative evaluation for non-cardiac surgery, the tumor was diagnosed coincidentally by echocardiographic examination. Echocardiography findings were consistent with a large left atrial myxoma originating from the posterior wall and prolapsing into the left ventricular cavity through the mitral valve, causing mitral stenosis. The mass was successfully completely excised. Histologic examination of the mass confirmed the diagnosis of cardiac myxoma. We report a casual echocardiographic finding of a left atrial myxoma that obstructed the mitral valve outflow tract, and an unrelated, synchronous cutaneous squamous cell carcinoma in the sacral area.