A 49-year-old woman was admitted in May, 1984 because of severe lumbago. A diagnosis of nonsecretory myeloma (BJ-λ) was made, based on the presence of multiple osteolytic lesions as well as bone marrow plasmocytosis with intracytoplasmic immunoglobulins of a monoclonal BJ-λ type but on the absence of detectable monoclonal immuno-globulins in either serum or urine. After chemotherapy with cyclophosphamide, the patient was improved. In July 1985, a relapse associated with pleural effusions and hypercalcemia occurred. Abnormal cells in pleural effusions had been proved to be plasma cells micro- as well as electron-microscopically. These cells were positive for OKT10 and PCA-1 and contained intracytoplasmic λ light chains. A cytogenetical analysis was performed on myeloma cells in pleural effusion. A total of 27 metaphase cells was analized. A chromosomal abnormality of t (14; 18) (q32; q21) was observed consistently. In addition, t (1; 7), t (2; 7), del (16) (q11), i (16q) and t (11; 20) were found in almost all the metaphases examined.
A 14q+ marker chromosome derived from t (14; 18) (q32; q21) has been considered to be relatively specific to follicular lymphoma and diffuse lymphoma. However, its occurrence has not been reported in plasma cell dyscrasia.