A 51-year-old woman with biopsy-proven sarcoidosis and a history of hypertension and ablation of atrioventricular nodal reentrant tachycardia underwent cardiac assessment. She had normal electrocardiogram (ECG). Normal left ventricular ejection fraction of 67% and slightly impaired global longitudinal strain of –18.5% were found on transthoracic echocardiography. Consequently, cardiac magnetic resonance (CMR), 24-hour ECG, exercise stress test, and continuation of angiotensin-converting enzyme inhibitor treatment were ordered. The treadmill test showed good exercise tolerance without ischemia. Atrioventricular block and ventricular arrythmias were absent on 24-hour ECG monitoring. CMR showed no features of cardiac sarcoidosis (ie, no late gadolinium enhancement, no features of ongoing inflammation), but a 9-mm tumor, not visible on transthoracic echocardiography, was found in the left atrium near the fossa ovalis (Figure 1A). Transesophageal echocardiography confirmed the presence of the tumor with morphology and location typical of myxoma (Figure 1B). Coronary angiography was normal. The patient subsequently underwent tumor resection. Histopathologic examination confirmed a myxoma (Figure 1C), however, B-cell infiltration was found at the base of the tumor. Small B-cells with immunophenotype CD20+, CD23+, CD5+ (Figure 1D–1F), CD3-, cyclin D1-, and Ki67 represented 7% of cells, which indicated chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma. Bone marrow biopsy showed small cell infiltration (75% of nucleated cells). Low number of B-cells with probable clonality was found in the peripheral blood. Small B-cell lymphoma with bone marrow and heart involvement was diagnosed. The patient was followed-up by a hematologist and a cardiologist without indications for immunosuppression and / or oncological treatment. At 3 years from the diagnosis, she remained asymptomatic, and no lymphadenopathy, significant peripheral blood abnormalities, or tumor recurrence were noted.

Figure 1. A – cardiac magnetic resonance; 4-chamber systolic still frame from routine balanced steady state free precession cine sequence showing a small, slightly mobile left atrial mass (arrow) attached to the interatrial septum near the fossa ovalis (Siemens Aera 1.5 T, Erlangen, Germany); B – 3-dimensional transesophageal echocardiography showing a left atrial tumor (arrow) attached to the interatrial septum near fossa ovalis. Tumor morphology and location are typical of myxoma; C–F – histopathologic examination: myxoma masses protrude into the lumen of the atrium, on the opposite side of the atrium wall there is an infiltrate of small, monomorphic B lymphocytes (C; hematoxylin and eosin staining, magnification × 100). Positive expression of CD23 (D), CD5 (E), and CD20 (F) in the lymphoid infiltrate (immunohistochemical staining, magnification × 100).

Primary cardiac tumors are rare, with an incidence of 0.02% in autopsy series.1 According to a registry of 38 cardiac surgery centers in Poland, every year 140 to 170 patients undergo surgery due to suspected intracardiac tumor.2 Seventy-five percent of the primary cardiac tumors are histologically benign. The most common primary cardiac tumor, myxoma, may have a malignant clinical course due to embolic potential, with 1% recurrence rate.3 Lymphomas are usually secondary tumors and occur by dissemination. Primary cardiac lymphomas are extremely rare, representing 5% of primary cardiac malignancies, with increased prevalence in immunocompromised patients, and poor prognosis.3 Sarcoidosis is a rare, systemic, immune-mediated, granulomatous disease with unknown etiology and morbidity of 10 per 100 000 people per year. Cardiac involvement may result in ventricular arrhythmias, sudden cardiac death, atrioventricular or bundle branch blocks, or progressive heart failure. Due to increased risk of cardiovascular events, patients with extracardiac sarcoidosis should undergo periodic cardiovascular assessment.4

Single reports on comorbid lymphoma / CLL have been published to date, some hypothesizing on the existence of shared pathogenetic mechanisms, where immunosuppression or chronic inflammation may play a role.5 To the best of our knowledge, no cases of sarcoidosis coexisting with both myxoma and CLL / lymphoma have been reported to date. However, our case seems to support the hypothesis on the putative role of chronic inflammation in the pathogenesis of myxoma coexisting with lymphoma.