Blastic transformation of splenic lymphoma with villous lymphocytes after a well-controlled chronic phase of more than 10 years

A 30-year-old Japanese man with splenomegaly and lymphocytosis was examined in 1985. Blood analysis revealed that some of the lymphocytes had short-su rface villi with polar distribution. The cells showed Ig lambda+,CD5+, CD11 c+, CD19+, CD22+,CD23+, CD24+, FMC7+ phenotype. A small M peak was detected in the serum. Splenic lymphoma with villous lymphocytes (SLVL) was diagnos ed on the basis of these findings. Remission was induced and was maintained with low-dose chlorambucil for more than 10 years. In 1996, the patient de veloped splenomegaly and lymphadenopathy with "B" symptoms and a high serum lactase dehydrogenase (LDH) level. Large blastoid cells with prominent nuc leoli were observed in the bone marrow; later, a small number appeared in t he peripheral blood. The bone marrow cells showed a complex chromosomal abn ormality involving del(7)(q32). Southern blot analysis of immunoglobulin ge ne rearrangements in SLVL cells that had been cryopreserved in 1986 and of bone marrow cells in 1996 showed 2 rearranged bands in each cell sample; 1 band showed identical sizes in the 2 samples, and the other showed differen t sizes. These findings suggest that the blastoid cells were derived from S LVL cells through transformation. After this transformation, the disease fo llowed a highly aggressive course. Various chemotherapeutic agents had litt le effect, and the patient died 3 months later. (C) 2000 The Japanese Socie ty of Hematology.