Abstract
A 39-year-old female was admitted because of marked gum swelling. A diagnosis of IgA λ plasma cell leukemia (PCL) was made based on the labolatory findings. Cytogenetic study of bone marrow revealed complicated chromosome aberrations. Gum biopsy disclosed a diffuse infiltration of atypical plasma cells and aspiration biopsy of the pleura, when effusion was noted in her terminal stage, also showed malignant plasma cell infiltration. Although the patient was treated with two courses of combination chemotherapy and direct administration of ACNU into the thoracic cavities, she died two months after diagnosis.
PCL is a rare form of plasma cell dyscrasia with a rapidly progressive fatal clinical course; its incidence is estimated to be 2% among all plasma cell dyscrasias. Although primary PCL without evidence of previous myeloma is characterized by frequent multiple organ involvements, there has been no detailed study with adequate pathological examination of gum infitration in PCL.
Interestingly, four out of seven cases of PCL with pleural effusion in the literature including our case were IgA type. There have been a few reports which suggest preponderance of the IgA type among multiple myeloma cases with extensive or microscopic extraosseous invasions. These reports and our case lead to the speculation that IgA type malignant plasma cells has propensity to infiltrate extramedullar organs than other types of plasma cells.
