Chromosomal Translocation Involving the Immunoglobulin Kappa-Chain and Heavy-Chain Loci in a Child with Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia is usually a monoclonal B-cell neoplasm that occurs almost exclusively in middle-aged and elderly adults. We observed a rapidly progressive case of the disease in a 10-year-old girl. The leukemic cells bore surface IgM and IgD immunoglobulins of the kappa-light-chain type. Karyotyping of the abnormal cells revealed an unusual translocation [t(2;14) (p13;q32)], with break points at or near the kappa-light-chain and heavy-chain gene loci. Translocations involving the immunoglobulin gene loci may be important in the pathogenesis of some cases of chronic lymphocytic leukemia, as they appear to be in Burkitt's lymphoma. (N Engl J Med 1983; 309:590–4.) CHRONIC lymphocytic leukemia is usually a monoclonal B-cell neoplasm 1 , 2 of middle-aged and elderly adults. Although rare cases have been reported in children, 3 4 5 none has been studied with modern immunologic and cytogenetic techniques. We have recently diagnosed chronic lymphocytic leukemia in a 10-year-old girl, whose leukemic cells expressed IgM and IgD kappa membrane immunoglobulins. Cytogenetic analysis showed a balanced 2p/14q translocation — an unexpected abnormality in this disease. 6 The exchange of genetic material between the short arm of chromosome 2 and the long arm of chromosome 14 occurred at bands p13 and q32, respectively. This finding is of great interest, since . . .