Management of Patients with 10-19% Bone Marrow Blasts

Disease Classification and Risk Assessment

Patients with 10-19% bone marrow blasts fall into a critical diagnostic category that represents higher-risk myelodysplastic syndrome (MDS) or early transformation to acute myeloid leukemia (AML), and should be risk-stratified using the International Prognostic Scoring System (IPSS) 2, 3
The IPSS incorporates bone marrow cytogenetics, blast percentage, and number of cytopenias to determine the risk category, with patients with 10-19% blasts typically falling into the Intermediate-2 or High risk IPSS categories 3
Cytogenetic analysis is essential for these patients, as the presence of poor-risk cytogenetics further worsens prognosis and may influence treatment decisions 4

For transplant-eligible patients, upfront allogeneic hematopoietic stem cell transplantation (allo-HCT) without prior disease-modifying treatment is the preferred approach to maximize chances of long-term survival, as recommended by the American Society of Hematology 1
Hypomethylating agents (HMAs) such as azacitidine or decitabine are recommended for patients who cannot proceed immediately to transplant, with the goal of reducing blast percentage and controlling disease progression 5

All transplant-eligible patients with 10-19% blasts should be considered for allo-HCT as the only potentially curative option, with bridging therapy with hypomethylating agents possibly considered before proceeding to transplant 1, 5
Iron chelation therapy should be considered for transplant candidates with serum ferritin levels exceeding 1000 μg/L to reduce transplant-related complications 1

Regular bone marrow evaluations should be performed to assess treatment response, with complete remission defined as <5% blasts with normal maturation of all cell lines, according to the International Working Group (IWG) criteria 2, 6
Disease progression is defined as a 50% or more increase in blasts to >20% blasts for patients with 10-20% blasts at baseline, and transformation to AML is defined as progression to ≥30% blasts 2, 6

Red blood cell transfusions should be provided for symptomatic anemia, generally at hemoglobin thresholds of at least 8 g/dL, as recommended by the American College of Physicians 5
Platelet transfusions should be considered for severe thrombocytopenia or bleeding, and iron chelation therapy should be considered for patients receiving multiple transfusions, especially if serum ferritin rises above 1000-2500 U/L 5