T(14-19) BCL3 REARRANGEMENTS IN LYMPHOPROLIFERATIVE DISORDERS - A REVIEW OF 23 CASES/

The t(14;19)(q32.3;q13.2) is a rare but recurrent translocation found in patients with B-cell malignancies, mainly in chronic B-cell lymphop roliferative disorders. When occurring in chronic lymphocytic leukemia (CLL), atypical lymphocyte morphology and immunophenotype have been r eported. A high proportion of patients with CLL and t(14;19) are aged less than 40 years. t(14;19) is often associated with rapidly progress ive disease, and overall prognosis is poor compared to the expected su rvival in chronic lymphocytic leukemia and low-grade B-cell lymphoma. t(14;19) is rarely the sole cytogenetic aberration. Trisomy 12 is the most frequent associated abnormality, and is observed in 50% of cases. t(14;19) involves the BCL3 gene, which is located at the breakpoint o n chromosome 19 and is juxtaposed to the immunoglobulin heavy chain ge ne locus on chromosome 14 (often in the switch alpha region) in a ''he ad-to-head'' configuration. The translocation does not interrupt the t ranscriptional integrity of BCL3, but is associated with overexpressio n of this gene, which encodes an I kappa B-like protein and modulates the activity of the NF-kappa B transcription factors. The genes affect ed by overexpression of BCL3 remain to be identified. (C) Elsevier Sci ence, Inc., 1997.