CD5-Positive Primary Cardiac Diffuse Large B-Cell Lymphoma: A Case Study

Abstract

Primary cardiac diffuse large B-cell lymphoma (DLBCL) is exceeding rare, and the CD5 positive de novo cardiac DLBCL is even rarer. We did study on a recent case and did literature review. This is a 54-year-old male with left side chest pain, dyspnea, and left side deep vein thrombosis. CT found a cardiac mass measuring 13 x 6 x 5 cm in right atria and right ventricle, extending into pericardium and inferior vena cava (IVC) and involving right coronary artery. There was also pericardial and bilateral pleural effusion. Retroperitoneal lymphadenopathy up to 2cm was also noted. Surgical debulking and excisional biopsy were performed. Sections demonstrate solid sheets of discohesive malignant cells with associated large zones of tumor necrosis. Tumor cells have large, round to irregular nuclei with vesiculated cleared out chromatin and scant cytoplasm. There is focal marked nuclear pleomorphism with rare multinucleated cells to suggest an anaplastic morphology. Abundant mitotic activity and apoptotic debris are present. Immunohistochemistry and in-situ hybridization demonstrate the large cells are positive for CD45, CD20, Bcl-2 (strong), CD10, P53, Mum-1, CD5 and BCl6 with a high proliferative index (>90%) on Ki-67 stain. The immunoprofile is diagnostic for a large B-cell lymphoma. EBER is negative. Flow cytometry of a low viability specimen is negative. FISH studies at Mayo Clinic reveal positive Bcl6 gene rearrangement and negative Bcl2, Myc, IgH, or IgL gene rearrangements. Therefore, there is no evidence of double-hit lymphomas. The bone marrow was negative for involvement. De novo CD5 positive primary cardiac DLBCL is very rare, and often has anaplastic morphology. Only one recent case report was found, which shows similar morphologic features as our case. Our patient is currently undergoing R-EPOCH chemotherapy and waiting for bone marrow transplant.