Successful treatment of cardiac lymphoma showing right atrial mass involving free wall of right ventricle with rituximab plus chemotherapy

Abstract

A 79-year-old man with hypertension and diabetes mellitus had systolic ejection murmur that was auscultated over the right parasternal area when admitted for interferon therapy for chronic type C hepatitis in February 2008. The echocardiogram revealed a right atrial mass involving the tricuspid valve and the free wall of the right ventricle. A large mass occupied the right atrium, and a dilated right atrium and ventricle were revealed. Enhanced computed tomography and positron emission tomography showed two abnormal masses in the mediastinum and extending from the right atrium to the ventricle. Although no symptoms were presented, we considered the possibility of malignant tumors and had the patient transferred to this institution. Specimens of the mediastinal mass obtained by mediastinoscopic biopsy indicated malignant lymphoma (diffuse large B-cell). Mass size had clearly decreased after eight courses of chemotherapy with rituximab plus CHOP. Treatment of cardiac lymphoma is not established, but rituximab plus chemotherapy for malignant lymphoma improved the prognosis of this patient. These findings suggest the usefulness of echocardiography in evaluating malignant cardiac tumor and judging response to treatment.