[Burkitt's lymphoma occurring as a primary lymphomatous effusion]

A 39-year-old man was admitted with massive ascites. Specimens of ascitic fluid contained numerous cells with a FAB-L3 appearance, and small noncleaved cell lymphoma morphology. These cells expressed CD10, CD19, CD20, CD38, CD45, HLA-DR, and IgM antigens, and were positive for IgM and c-myc protein in cytoplasmic immunostaining tests. Clonal rearrangements of IgH and c-myc genes were detected by Southern blot analysis. No mass lesions were found by physical examination, and systemic computed photography did not reveal enlargement of lymph nodes, spleen, or liver. Bone marrow aspiration showed no infiltration of malignant cells. Ga scintigraphy indicated hot lesions only in the abdomen. These findings suggested that Burkitt's lymphoma had developed in the peritoneal cavity as a primary lymphomatous effusion. Chemotherapy with methotrexate, cyclophosphamide, vincristine, doxorubicin, etoposide, and dexamethasone was effective, and the patient has been free from the disease for 1 year since completion of consolidation treatment with autologous peripheral blood stem cell transplantation.