[Burkitt's lymphoma with monoclonal pattern (IgG, kappa type) of cytoplasmic immunoglobulin--clinical report and review of Japanese literature].

A 52-year-old male was admitted to the hospital because of abdominal mass. Bone marrow examination revealed 26% blasts, which morphology was L3 in FAB criteria. Abdominal tumor was resected and histologic feature of the tumor was malignant lymphoma, small non-cleaved cell, Burkitt's. Lymphoma cells from the resected tumor were cultured and a cell line was established. Cytological studies of the original tumor cells and the cell line revealed that the lymphoma was negative both for EBNA and EBV DNA, and possessed t(8;14) (q24;q32) in chromosome analysis. Surface antigens were positive for HLA-DR, CD19 and CD20, but negative for CD10. The lymphoma also expressed a monoclonal pattern (IgG, kappa type) both of surface immunoglobulin and cytoplasmic immunoglobulin. Thus, the lymphoma was originated from mature B-lymphocyte. We analysed clinicopathological findings of 216 patients who were reported as Burkitt's lymphoma in Japan. Of 35 cases examined for cell EBNA, 7 (20%) were positive for EBNA. Of 86 cases tested for surface immunoglobulin of tumor cells, 67 expressed IgM alone and 10 IgG alone on tumor cells. Cytoplasmic immunoglobulin of tumor cells was positive in 61% of patients. Of 11 cases positive for cytoplasmic immunoglobulin, IgM was detected in 8 patients and IgG only in our patient.