Primary cardiac B cell lymphoma in an immunocompetent patient

Primary cardiac lymphoma is a rare entity of extranodal lymphoma and is observed with increasing frequency in immunocompromised hosts. However, a considerable proportion of cardiac lymphomas still occur in immunocompetent patients. We report the case of a 55-year-old immunocompetent Japanese man with a large amount of pericardial fluid and the presentation of heart failure secondary to primary cardiac B cell lymphoma, which was diagnosed by cytological examination of pericardial fluid and imaging. The right atrium, right ventricle and pericardium were affected by the tumour, which encased the mid/distal portion of the right coronary artery (RCA). Pretreatment optical coherence tomography of the RCA demonstrated no tumour extension into the vascular structure but a focal mural thrombus. We initiated chemotherapy (steroid therapy then COP at half dose/R-CHOP/R-CHASE) [COP (C: Cyclophosphamide, O: Oncovin, P: Prednisolone) R-CHOP (R: Rituximab, C: Cyclophosphamide, H: Doxorubicin Hydrochloride, O: Oncovin, P: Prednisolone) R-CHASE (R: Rituximab, C: Cyclophosphamide, HA: high dose Cytarabine, S: Steroid, E: Etoposide)]with administration of low-dose aspirin to prevent possible ischaemic events. The patient had a good clinical course without adverse events except for transient pericarditis.