Diagnosis of MDS-EB is primarily based on bone marrow examination. A bone marrow biopsy is essential to evaluate the cellularity and the presence of blasts. Cytochemical stains, like myeloperoxidase and Sudan black B, help identify myeloblasts. In addition, flow cytometry can be used to immunophenotype the blasts, often showing abnormal expression of markers such as CD34 and CD117.
