Clinical and hematological correlates of aberrant immunophenotypic profiles in adult and pediatric acute myeloid leukemia at presentation

Abstract

Background: Aberrant phenotypes in acute leukemia have been reported with varying frequencies in independent studies and their association with prognostic factors is still a matter of debate. Aim: This study aims to identify the frequency of aberrant immunophenotypes in de novo acute myeloid leukemia (AML) and to evaluate their association with initial clinical and hematological features. Materials and Methods: A total of 181 patients of de novo AML were included during the time (July 2010-June 2012). The immunophenotype of all cases of AML was studied by using flow cytometry. Results: Aberrant lymphoid antigen expression was seen in 43.1% cases. Most frequent aberrant lymphoid antigen was CD7, seen in 26.5% cases. All French-American-British (FAB) subtypes except AML-M3 expressed aberrant lymphoid antigens. The expression was most common in AML-M4 in the current study. CD34 expression in AMLs was significantly associated with the expression of aberrant lymphoid antigens. Lymphoid antigen expression in adult AML was significantly associated with higher white blood cell (WBC) count (>50,000/mm3) and higher number of peripheral blasts (>70%). Conclusion: In summary, CD7 is the most common aberrant lymphoid antigen expressed in AML. FAB subtype AML-M3 is usually not associated with aberrant lymphoid antigen expression. AML cases with CD34 positivity are more likely to express aberrant lymphoid markers. The current study also supports that aberrant lymphoid antigen expression in adult AML is associated with adverse presenting hematological features (WBC count >50,000/mm3, peripheral blasts >70%). Pediatric Ly + AML cases are not associated with adverse presenting clinical and biological features.