Current Diagnostic Approach in Acute Myeloid Leukemia in the Republic of Macedonia: A Proposal for Minimal Screening-Based Clinical Stratification

Introduction

Acute myeloid leukemia (AML) represents a heterogeneous complex of disorders resulting from diverse mechanisms of leukemogenesis. Correct diagnosis of AML subtypes plays a central role for individual clinical risk stratification and therapeutic decisions. Motivated to improve and simplify the diagnosis and management of AML in the Republic of Macedonia, we conducted a prospective study at the University Clinic of Hematology.

Patients and Methods

A total of 76 adults (> 15 years of age; from an initial 77 tested) with acute leukemia who were consecutively admitted at the clinic were enrolled in the study. The aim of our study was to establish and standardize diagnostic approaches based on minimal screening tests that will facilitate risk-adapted therapy for each single AML patient. The diagnosis of acute leukemia was made by standard criteria of the French-American-British (FAB) Cooperative Study Group and confirmed by immunophenotyping bone marrow aspirates and/or peripheral blood samples following the criteria of the European Group for the Immunological Classification of Leukemia's (EGIL) and the British Committee for Standards in Hematology (BCSH).

Results

Our results showed that morphology and cytochemistry established lineage in 68 (89.4%) of patients. Immunophenotyping further revealed the exact lineage assignment of the blast cells in 11.8% of patients and also changed the lineage assignment in 3 patients and guided to implementation of specific molecular analyses for the further definition of some AML cases. Using an RQ-PCR assay we detected the presence of the fusion transcript PML/RARα in 5 patients and classified 10 more patients in the prognostic favorable genetic entity Core Binding Factor (CBF)-AML according to the presence of the abnormal fusion transcripts AML1—ETO, CBFβ—MYH11. Those results were essential for more appropriate single-patient therapeutic decisions.

Conclusion

Our multimodal diagnostic approach consisted of cytomorphology, cytochemistry, multiparameter flow cytometry, and molecular analyses improved the diagnosis and enabled individual clinical stratification in 38.2% of our AML patients.