Polysomy 8 in Egyptian patients with de-novo acute myeloid leukemia

Background: Tetrasomy, pentasomy, and hexasomy of the entire chromosome 8 (polysomy 8) are relatively rare compared with trisomy 8, which is one of the most common recurring aberrations in myeloid hematologic malignancies. Although polysomy 8 appears to adversely influence outcome, little is known about the prognostic significance of polysomy 8 in patients with acute myeloid leukemia (AML).Aim of the work: The aim of the present work was to study the numerical aberrations of chromosome 8 in Egyptian patients with AML and to clarify its role as a prognostic marker.Patients and methods: The present study was carried out on 76 newly diagnosed adult patients with AML. They were attending the Hematology Department of Ain Shams University Hospitals. They were subjected to conventional cytogenetic analysis using G-banding and fluorescence in-situ hybridization using a fluorophore-labeled centromeric probe for chromosome 8.Results: Metaphase and interphase fluorescence in-situ hybridization for detection of polysomy 8 was successfully performed on 72 samples. Patients were divided into two groups: group A comprised patients associated with polysomy 8 (20 patients; 27.8%) and group B comprised patients without polysomy 8 (52 patients; 72.2%). Group A patients had a statistically significant younger age compared with group B (P=0.04). A statistically significant association was seen between polysomy 8 status and hepatosplenomegaly, fever, and lymph node infiltration (P=0.03, 0.001, and 0.05, respectively) but insignificant difference regarding the presence of skin or central nervous system infiltration (P 0.05). The presence of hepatosplenomegaly, skin infiltration, lymph node infiltration, and French–American–British subtype was shown to have a significant impact on patient outcome (P=0.05, 0.03, 0.01, and 0.04, respectively). Patients with skin infiltration, CD34 expression, HLA-DR expression, high/intermediate cytogenetic risk, and presence of polysomy 8 had significantly shorter overall survival.Conclusion and recommendations: From the current study we conclude that polysomy 8 occurs in 27.8% of de-novo AML cases; 35% of these cases showed tetrasomy of chromosome 8. Polysomy of chromosome 8 was associated with shortened overall survival. Further studies with a larger number of patients are recommended for proper assessment of polysomy 8, especially tetrasomy 8, among Egyptian patients with AML.