Abstract
We encountered a 66-year-old woman with fever, night sweats, and abdominal distension for 3 weeks. On examination, the liver was enlarged to the pelvic cavity and the spleen was felt 3 finger-breadths below the left costal margin. There was no superficial lymphadenopathy. Her hemoglobin level was 10.7 g/dL,white blood cell count was 4,600/μL, including 23.0% lymphoma cells, and platelet count was 82.0×103/μL. Lactate dehydrogenase was 1,320 IU/L, soluble interleukin-2 receptor was 334 U/mL, and ferritin was 64 ng/mL. 18F-fluorodeoxyglucose (FDG) positron emission tomography revealed the diffuse accumulation of FDG within the liver and spleen in addition to the bone marrow in the central skeleton. The bone marrow had 80% cellularity, including 90.2% lymphoma cells with CD5+, CD10-, CD19+, CD20+, CD21-, CD22+, and CD23- immunophenotypes and expressed μ/κ immunoglobulins. There were no hemophagocytic findings. Biopsies of the bone marrow revealed large lymphoma cells that were clustered or formed cellular nests within the sinusoids. The karyotype had multiple numerical and structural abnormalities, including trisomy of the long arm of chromosome 3 and tetrasomy of the long arm of chromosome 18. Although the present case exhibited features that overlapped with CD5-positive diffuse large B-cell lymphoma and intravascular large B-cell lymphoma, both of which have been shown to have poor clinical outcomes, the lymphoma responded very well to cyclophosphamide, doxorubicin, vincristine, and prednisolone in combination with rituximab, and long-term disease-free survival was expected.
