Acute promyelocytic leukemia (APL/AML-M3) is a distinct subtype of acute myelogenous leukemia, which is characterized by unique morphologic, cytogenetic, molecular, and clinical features. In almost all APL patients, a characteristic t(15;17)(q22;q21) is found, resulting from the fusion of the PML gene and retinoic acid receptor alpha (RARα)gene. This chromosomal translocation in APL may present variant translocations, and may be associated with secondary chromosomal abnormalities. The most frequent accompanying karyotypic aberration is trisomy 8 in APL.
We are reporting a case of a 17-year-old woman who was diagnosed with APL. Cytogenetic study revealed that 46, XX, del(5)(q23)/47, XX, del(5)(q23), ＋8 chromosomal abnormality but without t(15;17). However, the presence of PML/RARα chimera was found with reverse transcriptase PCR. It is well known that the association of trisomy 8 on top of t(15;17) in APL cases. However, in our review, the mosaicism of del(5)(q23) with trisomy 8 in APL might be the first case. Whether this patient will behave the
typical APL cases having good prognosis or not will be interesting to see.

Keywords: Acute promyelocytic leukemia, Chromosomal abnormality, PML/RARα,