Clinical examination of the patient led to the discovery of a heart murmur upon auscultation, and a palpable abdominal mass: both important findings that formed the basis for subsequent diagnostics. Echocardiography is a non-invasive procedure that in skilled hands can provide a great deal of information about cardiac function. Estimating the pump function of the heart and evaluating the status of the valve apparatus are the two most important matters.
Examination of the patient revealed a cardiac mass with a significant narrowing of the tricuspid ostium, which largely explains why she had become so short of breath on the slightest exertion. Cardiac masses are rare (1). The main causes of cardiac masses are summarised in Table 1. Biopsy is the key to further diagnosis, but represents an invasive procedure with a not insignificant morbidity and mortality risk.
Classification of cardiac masses, modified from Kassop et al (1)
Large coronary artery aneurysms
The patient was also found to have an abdominal mass, and although it was not possible to establish a definitive connection between these two findings, it made sense to perform the initial biopsy here as this was technically more straightforward. Rapid pathological analysis is important in such cases to allow prompt initiation of targeted treatment; in our patient this was performed on the basis of potentially vital indication.
Corticosteroid therapy was started before the final histology results were available. Corticosteroids have a general anti-inflammatory effect, in addition to a direct cytotoxic effect on lymphoid cells. Once the histology results were available, it was possible to begin a more targeted treatment of the cancer. It was important in this case to monitor the treatment response of both the primary abdominal tumour and the cardiac mass because a causal relationship between them had not been definitively established. The observed response (Fig. 3) was consistent with such a relationship.
While cardiac involvement is rare in lymphoma, it does occur, and then usually in the form of pericardial effusion (4, 5). Intracardiac masses as part of lymphoma are even more unusual, but may occur in disseminated disease (6); cardiac involvement is seen in 10 – 15 % of cases of advanced disease upon postmortem (7, 8). The right side of the heart is overrepresented in such cases, and the atria are overrepresented compared with the ventricles (6, 9). Multiple chambers are usually involved, as in our patient (10, 11).
Haematogenous spread is probably the most common cause of cardiac involvement. Thrombophilia with intracardiac thrombosis and secondary embolisation is not uncommon (12). The more malignant lymphomas, such as diffuse large B-cell lymphoma, Burkitt's lymphoma and some forms of T-cell lymphoma, appear to be overrepresented in cases of cardiac involvement (6, 11). Comorbidity in the form of immunosuppression and immunodeficiency, including HIV infection, increases the risk of cardiac affection in lymphoproliferative disorders (5, 6, 13).
Treatment of malignant processes involving the heart can be challenging with a not insignificant risk of complications. Fatal outcomes, including myocardial perforation, have been described, and the diagnosis is often first established upon autopsy (6, 9, 14). Treatment modalities include chemotherapy, radiotherapy and surgery.
Lymphomas are generally chemosensitive tumours, and chemotherapy is usually the first-line treatment, including in cases with cardiac involvement (9). In our patient, treatment was initiated with steroids in the form of dexamethasone and alkylating chemotherapy in the form of cyclophosphamide. Both steroids and cyclophosphamide have documented antineoplastic efficacy in lymphoproliferative disorders and are the cornerstones of lymphoma treatment (3).
This case history illustrates the importance of an interdisciplinary approach and rapid diagnosis of a rare disorder for allowing, as in this case, treatment with curative intent.