Case report: multimodality imaging to diagnose cardiac diffuse large B-cell lymphoma

Abstract

Background: Primary cardiac lymphoma (PCL) is rare and can present with a wide variety of clinical symptoms, frequently leading to a delay in diagnosis.

Case summary: We report a case of a PCL in an 81-year-old man. Cardiac magnetic resonance imaging showed multiple masses in the right atrium and a mass in the right ventricular outflow tract extending to the pulmonary artery. Biopsy revealed a diffuse large B-cell lymphoma. The patient also had metastases to the liver and lung on the positron emission tomography-computed tomography (PET-CT) scan. He was treated with R-CHOP chemotherapy, with complete remission documented PET-CT scans.

Conclusion: Although most patients with PCL die before chemotherapy can be initiated, a timely diagnosis can result in a favourable outcome.

Keywords: Cardiac MRI; Cardiac lymphoma; Echocardiography; Primary cardiac tumour.

Figure 1

Transthoracic echocardiogram: apical and subcostal four chambers view showing the mass in the right atrium measuring 23 ham× 45 mm.

Figure 2

Cardiac magnetic resonance imaging: (A) steady-state free precession of four chambers view showing three round isolated masses in the right atrium, all attached to its wall, measuring 11 mm × 9 mm, 33  mm × 29 mm, and 14 mm × 9 mm, respectively. (B) Different views of steady-state free precession showing the right atrium masses and the right ventricular outflow tract mass right ventricle outflow tract.

Figure 3

Light microscopy of the patient’s diffuse large B-cell lymphoma. (A) H&E-stained section shows large lymphoid cells with pleomorphic nuclei, variably prominent nucleoli, and scant to moderate amount of cytoplasm. (B) Immunostain for CD20 outlines the membranes of the large B cells. (C) Immunostain for Ki67 showing a proliferation rate of 80–90% of neoplastic lymphoid cells. (D) Immunostain for MYC, positive in 50–60% of neoplastic cells. All magnifications ×200.

Figure 4

¹⁸F fluorodeoxyglucose positron emission tomography whole body. (Left) Pre-treatment with chemotherapy showed an intensely ¹⁸F fluorodeoxyglucose-avid globular right atrial tumour with additional metabolic components in right ventricle and right ventricle outflow tract. In addition, a nodule in the left upper lobe of the lung and a liver lesion on positron emission tomography were suspicious of metastases. (Right) Post-chemotherapy, showed no lymphoma.