مرکز منطقه ای اطلاع رساني علوم و فناوري - A child AML-M1 with CD79a, CD56, and CD5 coexpressions and misdiagnosed as biphenotypic acute leukemia

Abstract :

Biphenotypic acute leukemia (BAL) is defined as the existence of multiple antigen coexpression in leukemic blasts or two different types of blast population. In this study, a patient who was first diagnosed with BAL and later with acute myeloid leukemia M1 (AML-M1) is presented. The patient was four-year-old male and had complaints about high fever, fatigue, lack of appetite, and weight loss for two months. % 96 L2 type blasts were identified in bone marrow aspiration, and positive values for CD79a, CD56, CD5, CD13, CD33, and MPO were observed in flow-cytometry. These findings, evaluated on the basis of “European Group for the Immunological Characterization of Leukemias (EGİL)” criteria, suggested BAL. As the steroid treatment returned no response, the flow-cytometry findings were reevaluated based on “World Health Organization (WHO)” criteria. BAL was excluded and AML M1 was considered as a diagnosis. The positive values for CD79a, CD56 , and CD5 were evaluated as coexpression. Chemotherapy was given as AML treatment, and the dramatic response was reported. This case is presented to show that, using EGİL criteria to evaluate BAL may be misleading , and thus using WHO criteria to evaluate BAL may be more appropriate.