Right atrial heart myxoma, two different presentations of the same entity and histopathological findings

Introduction: Cardiac myxomas are the most common primary neoplasms of the heart. The most common location is the left atrium (75%), followed by the right atrium (15-18%) and left ventricle. They may present with the triad of obstructive, embolic and constitutional symptoms. Case 1: a 59-year-old man under follow up for non-Hodgkin cutaneous T cell lymphoma, suffering from progressive dyspnea, was found to have a mass located on the right atrium. Resection of the tumor was performed, and replacement of the mitral valve due to severe mitral regurgitation. Histopathology confirmed the diagnosis of myxoma. Case 2: a 61-year-old woman presented with thrombosis in the basilic, cephalic and right jugular veins. An echocardiogram showed an 80 × 40 mm cardiac mass in the right atrium. On the histopathological report, a cardiac myxoma with the greatest diameter of 7.5 cm was reported. The patient was discharged nine days after surgery. Conclusion: There could be an unusual presentation of atrial myxoma occurring simultaneously with a neoplasm of different lineage. Atrial myxoma should be suspected even in unusual locations and regardless of concomitant neoplastic disease. Embolic phenomena, as the first presentation, may be misleading, although some parameters and scores might be useful predictors.