Conflict of interest: Nothing to report.
Images in Hematology
Concurrent chronic lymphocytic leukemia and prolymphocytic leukemia derived from two separate B-cell clones†
Article first published online: 4 APR 2011
Copyright © 2011 Wiley-Liss, Inc.
American Journal of Hematology
Volume 86, Issue 9, page 782, September 2011
How to Cite
Cao, F., Amato, D. and Wang, C. (2011), Concurrent chronic lymphocytic leukemia and prolymphocytic leukemia derived from two separate B-cell clones. Am. J. Hematol., 86: 782. doi: 10.1002/ajh.21970
- Issue published online: 17 AUG 2011
- Article first published online: 4 APR 2011
- Accepted manuscript online: 22 DEC 2010 06:31PM EST
- Manuscript Accepted: 15 DEC 2010
- Manuscript Revised: 8 DEC 2010
- Manuscript Received: 24 NOV 2010
An 82-year-old man presented with leukocytosis and splenomegaly. His blood counts showed a white cell count of 134 × 109/l, hemoglobin 96 g/l, and platelet count 86 × 109/l. The blood film showed two distinct populations of lymphocytes, morphologically, 60% typical CLL cells and 40% large prolymphocytes (Image 1). Patient's spleen was palpable 14 cm below the left costal margin. There were mildly enlarged cervical and axillary lymph nodes up to 2 cm but no evidence of localized lymphoma.
Flow cytometry analysis showed 90% B lymphocytes. Although all the B cells had lambda light chain restriction, they were heterogeneous for CD5 and CD23 expression, including the CD5+/CD23+ B cells typical of CLL phenotype, and the cells lacking CD5 and CD23 consistent with a PLL population. Clonality analysis was performed with use of multiplex PCR (polymerase chain reaction) assays for IgH rearrangement. With this assay, a clonal B-cell population gives rise to PCR product identical in size and independent clones can be distinguished by unique size of the PCR products. The patient's blood sample showed a pattern of two clones of B lymphocytes (Image 2), indicating the two independent clones of CLL and PLL cells.
The patient was treated initially with chlorambucil 2 mg daily with a poor response. His white cell count rose quickly to 240 × 109/l in 5 months. He required transfusion for worsening anemia. Further treatment with fludarabine and cyclophosphamide was tried and discontinued due to poor intolerance.
This patient presented with a mixed population of CLL and PLL. The genetic relationship between CLL and PLL may be revealed by immunoglobulin isotypes or immunoglobulin gene rearrangements . Similar to diffuse large B-cell lymphoma developing in CLL (Richter syndrome), B-cell PLL may arise from clonal progression of CLL or a second malignancy unrelated to CLL [1–3]. It is likely that this patient had an indolent and undiagnosed CLL, but the duration of CLL before the emerging PLL is unclear. Nonetheless, the finding of clonality analysis indicates PLL derived from an independent clone to that of CLL.