[A case of aggressive myeloma with abnormal plasmocytes in pleural effusion and cerebrospinal fluid]

Extramedullary involvement of myelomas is common but invasion of myeloma cells into the pleural cavity and cerebrospinal fluid (CSF) is rare. We report an aggressive case of multiple myelomas (Bence Jones lambda type) with pleural and meningeal infiltration. A 66-year-old man was referred to our hospital because of anemia, thrombocytopenia, and dyspnea. His peripheral blood contained 2% bizarre plasma cells. Bone marrow biopsy specimens and immunoelectrophoresis confirmed the diagnosis. A chest radiograph disclosed pleural effusion in both lungs containing M-protein and numerous abnormal cells. The patient also suffered from disorientation, speech disorder, and muscle weakness. A lumbar puncture revealed atypical plasma cells in CSF. Four courses of chemotherapy (cyclophosphamide, doxorubicin, and prednisolone) and the intrathecal administration of methotrexate and cytarabine at 3-week intervals were effective in decreasing the pleural effusions and eliminating plasma cells from CSF. Nonetheless a chest wall tumor, pelvic mass, and pneumonia developed, and the patient died 5 months after initial presentation. Pleural infiltration of myeloma cells and multiple lesions with plasma cell involvement were discovered at autopsy.