Browsing by Author "Todoric-Zivanovic, Biljana (13407686900)"

De novo AMLs with typical nonrandom chromosomal abnormalities are often associated with specific morphology subtypes. The t(8;21) is one of the most prominent recurrent cytogenetic aberrations (RCA) in AML, frequently associated with AML with maturation, and is characterized as a good prognostic marker. On the contrary, BCR::ABL1 rearrangement is rarely observed in AMLs, without specific morphology, carrying poor prognosis. Its distinction from blastic transformation of chronic myeloid leukemia has been a matter of long debate. The revised WHO classification (2016) recognized AML with BCR::ABL1+ as a provisional entity. The occurrence of additional cytogenetic aberrations in AML RCA within the same leukemic clone has been detected, albeit rare cases of BCR::ABL1+ were reported, mainly as subclones. Those additional cytogenetic and molecular findings seem to significantly affect patient prognosis. Conventional cytogenetic analysis, fluorescent in situ hybridization (FISH), and polymerase chain reaction (PCR) were applied at presentation and during the follow-up of the patient. We present a 34-year-old male patient with de novo AML harboring concomitant t(8;21) and t(9;22) in a single clone. The presence of both t(8;21) and Philadelphia chromosome (Ph+) in the same metaphases but in less than 100% of the analyzed cells, the p190 BCR::ABL transcript type, and absence of splenomegaly support that additional BCR::ABL1+ is a part of the main leukemic clone. These findings, accompanied with an encouraging outcome of continuous cytogenetic and molecular remission after induction therapy, support BCR::ABL1 being a secondary genetic event in AML with t(8;21). © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

Introduction. Additional karyotype abnormalities in the Philadelphia-positive (Ph+) clone can emerge during the progression of chronic myeloid leukemia (CML) and are of-ten associated with the resistance to treatment with tyrosine kinase inhibitors (TKI). Sometimes, during the TKI treat-ment, karyotype abnormalities can appear in the Philadelph-ia-negative (Ph-) cells as well but do not seem to adversely affect the outcome except for chromosome 7 abnormalities. Case report. The patient presented was in the chronic phase of Ph+ CML with highly diverse karyotype abnormal-ities. The abnormalities appeared in three unrelated clones during the TKIs treatment, followed by the evolution of the disease into acute myeloid leukemia (AML). The primary Ph+ clone was revealed during the chronic phase of CML, and therapy with imatinib mesylate was commenced. After a three-year hematologic and cytogenetic remission period, the evolution of the primary clone was noticed. Nilotinib was introduced, leading to a good molecular response and the disappearance/loss of the Ph+ clone with additional abnormalities but with the appearance of the Ph- clone with trisomy 8. Finally, after 5.5 years of nilotinib therapy, the Ph- clone with monosomy 7 occurred during the deep mo-lecular response for BCR-ABL. At that time, the FISH anal-ysis for trisomy 8 was negative, but the rise in blast count was noticed in the bone marrow, and the diagnosis of the secondary AML was established soon after. Conclusion. The achievement of the deep molecular response in CML patients does not rule out regular cytogenetic testing of their bone marrow. This is of crucial importance for detecting adverse karyotype abnormalities leading to the development of the myelodysplastic syndrome and AML. © 2021 Inst. Sci. inf., Univ. Defence in Belgrade. All rights reserved.