不明熱と高IgM血症を呈した悪性リンパ腫の1剖検例

Abstract

We report a case of an 80-year-old man with non-Hodgkin's lymphoma and high serum level of IgM. He was admitted to our hospital because of fever of unknown etiology and hoarseness. Seven weeks before the current admission, the patient was admitted to another hospital because of high fever, cough, and anasarca on January 26, 1994. High serum level of IgM was detected by immunoelectrophoresis in February 1994. Laboratory tests on admission revealed leucopenia (2,200/μl), high serum level of LDH (1,012IU/l) and IgM (1,509mg/dl). An abdominal computed tomographic (CT) scan revealed hepatosplenomegaly without lymphadenopathy. The patient was diagnosed as having non-Hodgkin's lymphoma (small lymphocytic + plasmacytoid) by autopsy. Lymphadenopathy was not detected, but tumor cells were microscopically detected in jugular, axillary, mediastinal, and adbominal lymphnodes. Also tumor cells had infiltrated to the liver, kidneys, spleen, and pancreas. Immunohistochemical staining for anti-IgM, IgG, κ-light chain, and λ-light chain showed positive in lymphoid cells. We experienced a difficult case to diagnose as malignant lymphoma for lack of lymphadenopathy.