t(14;19)(q32;q13): a recurrent translocation in B-cell precursor acute lymphoblastic leukemia.

The recurrent t(14;19)(q32;q13) translocation associated with chronic B-cell lymphoproliferative disorders, such as atypical chronic lymphocytic leukemia, results in the juxtaposition of the IGH@ and BCL3 genes and subsequent overexpression of BCL3. We report six patients with B-cell precursor acute lymphoblastic leukemia who have a cytogenetically identical translocation with different breakpoints at the molecular level. Fluorescence in situ hybridization with locus-specific probes confirmed the involvement of the IGH@ gene but showed that the breakpoint on 19q13 lay outside the region documented in t(14;19)(q32;q13)-positive chronic lymphocytic leukemia. This newly described translocation constitutes a distinct cytogenetic subgroup that is confined to older children and younger adults with B-cell precursor acute lymphoblastic leukemia.