[Primary splenic CD8-positive diffuse large B-cell lymphoma]

A 71-year-old woman was admitted for further examination of an increased serum LDH level. Abdominal ultrasonography and CT scan showed a large tumor in her spleen. Because malignant lymphoma was suspected, the spleen was removed for diagnosis and treatment planning. The histopathological and immunohistochemical features of the tumor indicated diffuse large B-cell lymphoma (DLBL). The flow-cytometric immunophenotype of the lymphoma cells was CD2-, CD3-, CD4-, CD5-, CD8+, CD10+, CD19+, CD20+, CD23-, kappa+, lambda-, CD25+, and CD56-. From these findings, the patient was diagnosed as having CD8+ DLBL. To our knowledge, this is the first reported case of primary splenic CD8-positive DLBL.