RESUMO
<p><b>OBJECTIVE</b>To report an acute promyelocytic leukaemia (APL) case with translocation of rob (13;21) t(15;17) (q22;q21) and review its clinical and laboratory characteristics.</p><p><b>METHODS</b>Based on routine karyotype analysis and bone marrow morphology, we further used double color double fluorescent in situ hybridization (DCDF-FISH) and reverse transcriptase PCR (RT-PCR) to examine the patient's abnormities on cytogenetic and molecular biology, and reveal the clinical characteristics of this rare translocation also from the related literatures.</p><p><b>RESULTS</b>The clinical manifestation and bone marrow morphology examination of this patient were in accordance with pathologic feature of APL. On first visit, immunophenotyping analysis showed positive myeloid markers. Through R-banding, the patient's karyotype was confirmed as 45, XX, rob(13;21) t(15;17) (q22;q21) [6]/45, XX, rob(13;21) [14]. FISH results showed that 68.9% cells were typical t(15;17) pattern. The positive rates of fusion gene of PML-RARα detected by RT-PCR was 25.8%. Patient was treated by induction and consolidation therapy, the karyotype was 45, XX, rob(13;21 )[20] after complete remission. The positive rate of fusion gene of PML-RARα by FISH and its level were 2.5% and 0.003% respectively.</p><p><b>CONCLUSION</b>APL with rob (13;21) t(15;17) (q22;q21) was very rare, which was accorded with clinical and laboratory characteristics of APL. The value of chromosome abnormality as a prognostic marker in APL needs to be further observed..</p>
