ABSTRACT
@#Introduction: Acute myeloid leukaemia (AML) with t(8;21)(q22;q22) producing RUNX1-RUNX1T1 rearrangement is a distinct sub-type which is usually associated with a favourable clinical outcome. Variant forms of t(8;21) are rare. Herein we describe a novel variant of t(8;21) AML in a 25-year-old pregnant woman who presented with intermittent fever. Case Report: Her peripheral smear and bone marrow aspirate showed many myeloblasts. Chromosomal study revealed t(8;22;21)(q22;q12;q22) and loss of X chromosome. Fluorescence in situ hybridization (FISH) using whole chromosome painting probes confirmed the three-way translocation involving chromosomes 8, 21 and 22. RUNX1-RUNX1T1 rearrangement was identified in FISH and reverse transcriptase polymerase chain reaction confirming the diagnosis of AML with variant t(8;21). The patient was treated with standard chemotherapy. She achieved morphological remission one month after induction chemotherapy. Discussion: Although the clinical significance of variant t(8;21) is not well delineated, the evaluation of 31 such cases suggests patients with variant t(8;21) have similar prognosis to those with classical t(8;21).
ABSTRACT
The t(8;21)(q22;q22) is one of the most frequent structural chromosomal anomaly found in AML, occurring in about 5% of all AML and in 10% of AML with maturation (M2). And approximately 3.4% of AML with t(8;21)(q22;q22) occurs as a complex chromosomal abnormality and occasionally shows discrepancy between cytogenetic and molecular genetic analyses. We report a case of 42 yr old male patient that revealed morphological characteristics of AML-M2 and karyotypic abnormality of 45,X,-Y,t(8;17)(q22;p13) without visible involvement of chromosome 21 by conventional cytogenetic study with masked t(8;21) identified by FISH using RUNX1/RUNX1T1 probes. FISH confirmed nuc ish (RUNX1T1x3),(RUNX1x3), (RUNX1T1 con RUNX1x1). According to the results of conventional cytogenetic and FISH analyses, the karyotype was revised to 45,X,-Y,t(8;17;21)(q22;p13;q22).
Subject(s)
Humans , Male , Chromosome Aberrations , Chromosomes, Human, Pair 21 , Cytogenetics , Karyotype , Leukemia, Myeloid, Acute , Masks , Molecular BiologyABSTRACT
We report a case that revealed the characteristics of acute myeloblastic leukemia with maturation (AML-M2) on the morphology of the bone marrow biopsy and 45,X,-Y in conventional cytogenetic study, but was confirmed to have a typical AML1/ETO translocation by molecular studies using reverse transcriptase polymerase chain reaction and fluorescence in situ hybridization. Insertion of ETO gene on chromosome 8 into chromosome 21 in this patient resulted in the development of the chimeric gene, AML1/ETO, on the long arm of chromosome 21. Our final report on the patient's karyotype: 45,X,-Y.ish ins(21;8)(q22;q22q22)(AML1 +,ETO +;ETO +,AML1-). In case typical morphologic features compatible with recurrent cytogenetic abnormalities are shown, molecular studies in addition to conventional cytogenetic study might be required to confirm the diagnosis.