Keywords:

 ¨ cardiac lymphoma, ¨ superior vena cava obstruction.



Introduction


Primary cardiac lymphoma is defined as a non-Hodgkin’s lymphoma involving only the heart and/or pericardium with no or minimal evidence of extracardiac involvement, or as a lymphoma with the bulk of the tumor located in the heart. It is extremely rare in immunocompetent patients1, and unlike other cardiac malignancies it can respond to treatment. We present a recent example and review the literature on this rare lesion.


Case presentation


A 37-year-old man presented with a short history of intermittent pyrexia, neck swelling and dysphagia. The swelling rapidly progressed to involve his head, neck, upper limbs and upper chest. His full blood count at this time was hemoglobin 13.8 g/dl, white count 6.4x103/ul and platelets 332x103/ul.
While being investigated for presumed superior vena cava (SVC) obstruction he developed increasing respiratory distress and required mechanical ventilation. A computerized tomogram (CT) showed a thrombus and a mass within the lumen of the SVC extending into the right atrium. There were no other masses or evidence of external compression of the SVC. A transesophageal echocardiogram (TEE) confirmed a large mass arising from the interatrial septum and filling the right atrium (Figure 1)

Fig.1: Transoesophageal bicaval image showing large mass filling the right atrium and attached to the interatrial septum. Clefts within the mass are clearly visible (arrow).

 causing complete obstruction of the

SVC and the right atrial outlet through the tricuspid valve.
In view of his deteriorating clinical condition and both right atrial inlet and outlet obstruction, he underwent emergency cardiac surgery. Under bicaval cannulation and cardiopulmonary bypass, the right atrium was opened (Figure 2)

Fig.2: Smooth mass protruding through the incision in the right atrium.

and the mass debulked including the extension up the SVC (Figure 3).

 

Fig.3: Operative specimen - when the attachment to the interatrial septum was incised the mass fell into 3 ‘lobules’.

Due to invasion into the septum and extension into the angle between the right atrium and the ascending aorta complete resection was not possible. The intra-operative TEE shows residual interatrial septal thickening (Figure 4).

 

Fig.4: Transoesophageal image showing residual thickening of the interatrial septum (arrow).

Post-operatively there was dramatic improvement in the swelling with a 28kg weight loss over the following 10 days.

Histopathology revealed a malignant, diffuse B-cell Non-Hodgkin’s lymphoma positive for CD20. Following full staging he was transferred to the care of the oncologists for further management. His interatrial septal thickness (as assessed by echocardiography) decreased from 19mm to 10mm following his first three courses of chemotherapy.



Discussion


Primary cardiac lymphoma is defined as being exclusively located in the heart and/or pericardium and is extremely rare1. In immunocompetent patients it accounts for 1% of primary cardiac tumours and 0.5% of extranodal lymphomas, but in contrast 20% of disseminated lymphomas will have some cardiac involvement1. Cardiac lymphomas comprise less than 5% of all lymphomas arising in patients with AIDS and organ transplant patients. The mean age at presentation for cardiac lymphoma is 67 years, and the right atrium and right ventricle are the 2 most common sites2.
The tumour remains asymptomatic until it produces a mass effect obstructing chambers/valves, embolisation, heart rhythm abnormalities or cardiac tamponade3. There can also be the systemic effects associated with lymphoma such as pyrexia and weight loss. Most patients have an acute onset to a rapid demise if not treated quickly, with survival less than 1 month without treatment1.
Primary cardiac lymphoma has previously been reported with superior vena caval syndrome, but in a HIV-positive patient4, and in an elderly immunocompetent women diagnosed from cervical lymph node biopsy3. These two cases did not require emergency cardiac surgery. The patient presented here was HIV negative. Other presentations include atrioventricular block due to damage to the conduction system5 and ‘constrictive pericarditis’6 and mimicking left ventricular aneurysm with chest pain and mural thrombus7. Diffuse large B cell lymphoma has presented as a cardiac mass (left atrial) and odynophagia, but in that case the tumour was oesophageal in origin and invading the left atrium8.
Echocardiography, computerized tomography and magnetic resonance imaging (MRI) all help in the diagnosis. Echocardiography has the best spatial resolution of the cardiac imaging modalities providing excellent anatomical and functional information and can also assess the degree of obstruction and valve regurgitation. MRI has the highest soft tissue resolution of the imaging modalities so making it the most sensitive at detecting infiltration into chamber walls1.
Cardiac lymphoma may be B cell, follicular centre cell, immunoblastic, diffuse large cell and Burkitts lymphoma. Primary cardiac lymphoma, unlike other cardiac malignancies, responds to chemotherapy. Tumors with positive reactivity to CD20 are treated with R-CHOP (monoclonal CD20 antibody – Rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone). Treatment includes anti CD20 treatment and chemotherapy alone or combined with radiotherapy. Palliative surgery is usually reserved for debulking an obstructing lesion or if there is no other way to get a biopsy and should not be delayed if indicated.
Early diagnosis may be best made by echocardiography and transvenous/ endomyocardial biopsy9. A combination of chemotherapy and radiotherapy offers the best treatment option10.¨



References:

1. Gowda RM, Khan IA. Clinical perspectives of primary cardiac lymphoma. Angiology. 2003;54(5):599-604.

2. Burke A, Jeudy Jr J, Virmani R. Cardiac tumours: an update. Heart 2008;94:117-123.

3. Sato Y, Matsumoto N, Kinukawa N, Matsuo S, Komatsu S, Kunimasa T, Yoda S, Tani S, Takayama T, Kasamaki Y, Kunimoto S, Furuhashi S, Takahashi M, Saito S. Successful treatment of primary cardiac B-cell lymphoma: depiction at multislice computed tomography and magnetic resonance imaging. Int J Cardiol 2006;113(1):E26-29.

4. Matsuo S, Sato Y, Miyamoto A, Nakae I, Saeki M, Hodohara K, Horie M. Primary malignant lymphoma of the right atrium resulting in superior vena caval syndrome in an HIV-positive patient: depiction at multislice computed tomography and magnetic resonance imaging. Cardiovasc Revasc Med. 2006;7(4):255-7.

5. Montiel V, Maziers N, Dereme T. Primary cardiac lymphoma and complete atrio-ventricular block: case report and review of the literature. Acta Cardiol 2007:62(1):55-8.


6. Ho HH, Kwok OH, Chui WH, Wang E, Chau MC, Chow WH. A rare cause of constrictive pericarditis: primary cardiac lymphoma. Int J Cardiol 2008;123(2):208-9.

7. Miller DV, Mookadam F, Mookadam M, Edwards WD, Macon WR. Primary cardiac plasmablastic (diffuse large B-cell) lymphoma mimicking left ventricular aneurysm with mural thrombus. Cardiovasc Pathol 2007;16(2):111-4.

8. Ban-Hoefen M, Zeglin MA, Bisognano JD. Diffuse large B cell lymphoma presenting as a cardiac mass and odynophagia. Cardiol J. 2008;15(5):471-4.

9. Abramowitz Y, Hiller N, Perlman G, Admon D, Beeri R, Chajek-Shaul T, Leibowitz D. Int J Cardiol 2007;118(2):e39-40.

10. Margolin DA, Fabian V, Mintz U, Botham MJ. Primary cardiac lymphoma. Ann Thorac Surg 1996;61:1000-1001.

 

IMAGES MITRAL VALVE DEHISCENSE