Cytogenetics, FISH and RT-PCR analysis of acute promyelocytic leukemia: structure of the fusion point in a case lacking classic t(15;17) translocation.

The chimeric gene product PML-RAR alpha, the result of a reciprocal t(15;17) translocation, plays an important role in the pathogenesis of acute promyelocytic leukemia (APL). In the present study on clinical effects of cytogenetics and molecular events in APL, we performed chromosome analysis, fluorescence in situ hybridization (FISH) using gene-specific probe, and reverse transcription-polymerase chain reaction (RT-PCR) analysis in 10 patients with APL. Patients were treated with all-trans retinoic acid (ATRA) and/or chemotherapy, and all achieved complete remission.