A 41-year-old female developed acute onset of right shoulder pain followed by anterior pleuritic chest pain on the morning of admission. She had had a similar episode approximately 1 month prior, which resolved spontaneously and was not as intense in nature. Her past medical history was only significant for well-controlled asthma and endometriosis. Labs were notable for a normocytic anemia. Chest x-ray showed an indistinct superior right heart border and right hilum. Cardiac magnetic resonance image showed a large mass filling the majority of the right atrium (Fig 1, arrow). This measured 3.5 × 6 × 5 cm and appeared fixed to the wall of the right atrium along the right anterior aspect. The mass was separate from the intra-atrial septum and did not involve the right ventricle. It extended superiorly, involving the junction of the superior vena cava and the right atrium. A transesophageal echocardiagram demonstrated a large, sessile right atrial mass with a multilobular appearance, with a broad base attached to the right atrial free wall and the wall of the superior vena cava. Ventilation perfusion scan showed no evidence of pulmonary emboli. The patient underwent surgical resection of the atrial mass and reconstruction of the right atrium with a patch graft. Pathology demonstrated an 8 × 6.8 × 3 cm diffuse large B-cell lymphoma involving the full thickness of the right atrium (Fig 2A and B). Immunoperoxidase stains were positive for leukocyte common antigen (CD45) and CD20/L26 B-cell marker (Fig 2C). Postoperatively, a computed tomography scan of the abdomen was notable for a complex left uterine mass, measuring 7.8 × 5.7 × 6.1 cm. Biopsy revealed only RBCs, possibly secondary to endometriosis. Positron emission tomography scan showed no residual disease in the right atrium and no areas of increased uptake. HIV testing was negative. Bone marrow biopsy was negative for lymphoma.

View larger version:

• In this window
• In a new window

• PowerPoint Slide for Teaching

Fig 1.

View larger version:

• In this window
• In a new window

• PowerPoint Slide for Teaching

Fig 2.

Primary cardiac lymphoma (PCL) is a rare entity with variable clinical presentations. It is defined as the presence of non-Hodgkin's lymphoma confined to the heart or pericardium.¹ Only 15 of 55 patients reported PCL from 1949 to 1989 and were found to meet the latter criteria.² PCL represents 1.3% of primary cardiac tumors and 0.5% of extranodal lymphomas. However, in another study, 12,485 autopsies were performed over a 20-year period and seven cases of PCL were noted.³ This represented an incidence of 0.056% in the general population. PCL occurs more commonly in immunocompromised patients, with a significant increase noted in the presence of HIV-positive individuals.^4,5 The etiology of this association is unclear. It is exceedingly uncommon in the immunocompetent population. Initial signs and symptoms, though primarily cardiovascular in etiology (eg, shortness of breath, palpitations, chest pain, syncope, arrhythmia, congestive heart failure, or pericardial effusion) may often be illusive.⁶ Our patient is the first reported case of pleuritic chest pain as the initial symptom. Management of PCL is varied.⁴ Due to the frequent association with an immunocompromised patient,⁵ the prognosis and therapy of this entity is variable.⁶ For stage I non-Hodgkin's lymphoma, randomized trials support the use of chemotherapy alone or an abbreviated course of chemotherapy followed by involved field radiation. Since this patient had a complete surgical resection of her disease, only anthracycline-based chemotherapy is planned, owing to a risk of relapse.

Authors' Disclosures of Potential Conflicts of Interest

The authors indicated no potential conflicts of interest.