Abstract
Background : The incidence of primary cardiac tumors is rare, and primary cardiac lymphoma (PCL) is extremely rare. We report herein on the cytological findings in pleural effusion from a patient with PCL.
Case : In an 80-year-old man admitted for suspected heart failure, computed tomography revealed a tumor in the right atrium. Right pleural effusion cytology specimens showed sporadically isolated atypical cells. As the atypical cells were medium to large with a bare-nucleus-like shape, malignant lymphoma was suspected. Following the patient's death, the autopsy revealed the presence of a solid tumor, mainly localized in the right atrium and filling the pericardial cavity around the heart. Histologically, the diffuse invasion of markedly large, round, atypical tumor cells was observed. On immunohistochemical staining, the tumor cells were shown to be positive for CD20 and CD79a, and negative for CD3, CD5, and CD10. Based on these findings, the tumor was diagnosed as a diffuse large B-cell lymphoma, NOS. Further, in the absence of apparent lesions of malignant lymphoma in organs other than the heart and lymph nodes, this example was considered to be a PCL.
Conclusion : PCL has a poor prognosis, and tissue biopsy is sometimes difficult to perform. Imaging tests in combination with cytological analysis could help in the early diagnosis of PCL.
