A 61-year-old woman was admitted to Tokyo Modical College Hospital in January 1987 because of anemia and bone pain of the sternum.
Hematological findings were as follows; hemoglobin 4.7g/dl, platelet count 15.7×104/μl, WBC count 2, 100/μl with 54% small lymphocytes. Bone marrow aspiration yielded a hypocellular marrow with 80.6% small lymphoid cells. A bone marrow biopsy specimen showed diffuse proliferation of small lymphocytes partially with the plasmacytoid differentiation. These small lymphocytes were found to have the surface immunogiobulin IgAκ by using immunofluorescent technique. Laboratory findings disclosed M-component of IgAκ type in the serum. Skeletal X-ray film surveys no osteolytic lesions.
From these findings, she was diagnosed as having IgAκ producing B cell malignancy diffuse lymphoma, small cell type partially with the plasmacytoid differenciation of LSG classification which origiated primarlly in the bone marrow.
This is thought to be a rare case situated between Waldenström's macroglobulinemia and multiple myeloma.
