Biclonal Gammopathy in Chronic Lymphocytic Leukemia: Case Report and Review of the Literature

Abstract

Monoclonal gammopathies are frequently seen in B-cell malignancies. Monoclonal proteins are seen in a significant proportion of patients with chronic lymphocytic leukemia (CLL), which is a clonal disorder of mature B cells. The use of more sensitive laboratory methods has enabled the detection of monoclonal proteins or light chains in the serum and/or urine in the majority of these patients. The presence of some of these monoclonal proteins may explain the different autoimmune phenomena that are associated with this disease. Some reports indicate that the finding of monoclonal proteins has a negative impact on patients' survival. The presence of two different monoclonal proteins (i.e. biclonal gammopathy) is on the other hand rare. Most of the reported cases in the literature are of patients with plasma cell disorders. In this report, we describe a rare occurrence of biclonal gammopathy in a patient with CLL. Serum protein electrophoresis and immunofixation, which were negative at the time of initial diagnosis, showed biclonal immunoglobin A (IgA) kappa and IgA lambda during the course of the disease. The patient's disease showed steady progression, despite multiple treatments. Although this could just be the result of using more sensitive laboratory techniques, biclonal gammopathy in this patient likely reflects the evolution of another clone, which would explain the encountered resistance to therapy. Because of paucity of reports, the impact of biclonal gammopathies in such patients is not known and an effort to collectively report the presentation and outcome of these patients is needed to further understand the pathophysiology and clinical significance of such a finding.

Keywords: Leukemia, B-Cell; Leukemia, Chronic Lymphocytic; Paraproteinemias.

Figure 1

Serum protein electro-phoresis (SPEP). (a) Normal control band and (b) patient’s serum showing a sharp band in the mid gamma region.

Figure 2

Patient’s serum protein immunofixation electrophoresis. Serum protein immunofixation shows two discrete IgA bands: an IgA lambda band in the beta region and an IgA kappa band in the mid-gamma region i.e. biclonal gammopathy. Key: G: IgG, A: IgA, M: IgM, K: kappa light chain, L: lambda light chain.