Introduction
Primary cardiac lymphoma (PCL) is an extranodal lymphoma which involves the heart and pericardium. It is a very rare tumor, representing 0.5% of all extranodal lymphomas and 1%–2% of primary cardiac tumors . PCL is most frequently detected in immune-compromised patients , predominantly in males (3:1 ratio) , with a median age of occurrence of 63 years although it can develop at any age . PCL is often an aggressive lymphoma, and the short-term prognosis is usually unfavorable with a high mortality rate, unless it is identified early and promptly treated . Cardiac lymphomas are infiltrative, intramural, with a specific tropism for the pericardium and the right side of the heart. The pericardium is affected in approximately 33% of cases . The right atrium is the most involved site followed by right ventricle, left atrium, atrial septum, and ventricular septum. However, multichamber involvement has been seen in up to 75% of cases .
PCL has no typical clinical presentation, and clinical characteristics are not distinctive, with variable symptoms depending on location, amount of cardiac structure infiltration, proliferation, and friability .
At present, diagnosis mainly relies on multiple imaging techniques that include echocardiography, cardiac computed tomography (CT), and cardiac magnetic resonance (CMR) .
Case report 1
A 79-year-old man, with no immunodepression, was referred to our outpatient clinic for moderate dyspnea (New York Heart Association Class, NYHA II), without signs of acute or unstable heart failure. A surface electrocardiogram (ECG) showed sinus tachycardia (110 bpm), right bundle branch block, and left anterior hemiblock ( Fig. 24.1 ). Blood pressure was 120/80 mmHg. Chest X-ray indicated obliteration of the right costophrenic sinus due to mild flap of pleural effusion ( Fig. 24.2 ).
The patient underwent CMR and CT imaging that confirmed the size of the mass and excluded additional extracardiac masses ( Figs. 24.5 and 24.6 A and B ).
The endomyocardial biopsy, performed by cardiac right catheterization, was consistent with the diagnosis of non-Hodgkin high-cell positive B-cell lymphoma, with positive immunophenotype for CD45, CD20; negative for cytokeratin pool, S-100 protein, synaptophysin, CD3, CD10, BCL-6, BCL-2, CD138, and for HHV-8; absence of rearrangement of the 8q24 (MYC) locus assessed by FISH.
After onco-hematologic evaluation, the patient started high-dose chemotherapy, according to the R-CHOP regimen (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) for 8 cycles.
Case report 2
A sixty-one-year-old woman presented at the Emergency Department for heart palpitation and worsening dyspnea. She was assuming antiarrhythmic therapy with flecainide for complex supraventricular arrhythmias.
ECG showed sinus rhythm, vertical axis, signs of right atrial overload, atrioventricular (AV) block grade I ( Fig. 24.7 ).
Chest X-ray did not report any major pathological findings ( Fig. 24.8 ).
Computed tomography imaging confirmed the presence of the mass in the right cardiac cavities (transverse diameter of about 7.5–8 cm) and evidenced presence of bilateral pulmonary pleural effusion more represented on the right side, causing atelectasis of the lower lung lobe ( Fig. 24.11 ).
Coronary CT scan excluded the presence of significant stenosis of the coronary tree, or direct infiltration or compression of coronary arteries.
An intracardiac biopsy was performed under transfemoral ultrasound guidance and the histopathological examination confirmed the diagnosis of diffuse large B-cell lymphoma. The immunophenotype of the neoplastic cells was positive for cardiac lymphoma and negative for AE1-AE3 cytokeratins. The proliferating index was 80%. Immunoreactivity was positive for CD79a and, focally, for CD20.
After onco-hematologic evaluation, the patient was assigned to high-dose chemotherapy, according to the R-CHOP regimen (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) for 6 cycles.
At present, after 5 years, at the age of 56, the patient is in complete remission, with good performance status.