Acute myeloid leukemia with rare cytogenetic abnormalities

Acute myeloid leukemia (AML) is a clonal hematologic disorder frequently linked to genetic alterations, accounting for approximately 31% of adult leukemia cases. Recent updates in the World Health Organization (WHO) and International Consensus Classification (ICC) have redefined AML into categories based on genetic abnormalities, emphasizing the role of cytogenetics in diagnosis, prognosis, and treatment. Cytogenetic and molecular analyses are increasingly supplementing conventional morphology and immunophenotype assessments. In AML, cytogenetic abnormalities are categorized into favorable, intermediate, and adverse risk groups. While common cytogenetic markers have been extensively studied, rare cytogenetic abnormalities in AML remain less understood, often posing challenges in prognostic evaluation and treatment strategies. This study presents a case series of seven AML patients, each exhibiting rare cytogenetic abnormalities that are not well-defined in the WHO's 5th edition classification of hematopoietic and lymphoid tissues. We retrospectively analyzed these cases, where AML diagnosis was confirmed through morphology, flow cytometry, immunohistochemistry, and molecular studies. Cytogenetic investigations included G-banding and fluorescence in-situ hybridization (FISH). The molecular studies performed as part of the AML multigene panel revealed notable genetic variations, including rare translocations and polysomies. This study highlights the significance of cytogenetic analysis in identifying rare abnormalities, which can influence risk stratification and treatment decisions. However, due to the limited literature and understanding of these rare cytogenetic events, more research is essential for optimizing patient outcomes.