What are the diagnostic criteria for Acute Myeloid Leukemia (AML)?

From the Guidelines

Acute Myeloid Leukemia (AML) diagnosis requires a comprehensive approach including blood tests, bone marrow examination, and specialized testing, as outlined in the most recent guidelines 1. The diagnostic process begins with a complete blood count (CBC) showing abnormalities like decreased red blood cells, platelets, and abnormal white blood cell counts.

Key Diagnostic Steps

• A peripheral blood smear examination is essential to identify blast cells.
• Bone marrow aspiration and biopsy are crucial, with AML diagnosis confirmed when at least 20% of cells in the bone marrow are myeloid blasts.
• Flow cytometry helps identify specific cell markers, while cytogenetic analysis and molecular testing detect genetic abnormalities like FLT3, NPM1, and CEBPA mutations that influence prognosis and treatment decisions.

Additional Tests

• HLA typing for potential stem cell transplantation candidates
• Lumbar puncture if central nervous system involvement is suspected
• Coagulation screening prior to the insertion of central venous lines
• Cardiac examination including echocardiography for patients with risk factors or a history of heart disease 1

Treatment Approach

• Treatment is divided into induction and consolidation chemotherapy, with a curative intent whenever possible.
• Candidates for allogeneic stem cell transplantation should be identified early during induction.
• Patients with poor performance status and considerable comorbidity, as well as elderly patients not eligible for curative treatment, should receive supportive care 1.

From the Research

Diagnosis of Acute Myeloid Leukemia (AML)

• The diagnosis of AML can be made based on peripheral blood or bone marrow blasts 2
• Bone marrow evaluation and peripheral blood monitoring play a crucial role in the diagnosis, management, and follow-up of AML patients 2
• The diagnosis of AML with myelodysplasia-related changes (AML-MRC) requires a comprehensive evaluation, including clinical history, cytogenetic analysis, mutational analysis, and/or morphologic evaluation 3

Diagnostic Criteria and Assessments

• The European Leukemia Network has published risk classification algorithms for both intensively and non-intensively treated patients based on cytogenetic and molecular findings 4
• Prognostic factors may differ based on the therapeutic approach 4
• Measurable residual disease (MRD) findings are increasingly being used to assess response and monitor disease status 4

Treatment and Management

• Treatment decisions for AML-MRC should be based on a clear understanding of the pathology information necessary for diagnosis 3
• The American Society of Hematology (ASH) has published guidelines for treating newly diagnosed AML in older adults, which recommend treatment over best supportive management and more-intensive therapy over less-intensive therapy when deemed tolerable 5
• The incorporation of MRD findings into therapeutic decision-making is rapidly evolving 4

Role of Bone Marrow Evaluation

• Bone marrow evaluation remains the de facto standard for response assessment in AML patients 2
• However, peripheral blood evaluation may be adequate for monitoring relapse, although bone marrow testing may have superior sensitivity in some cases 2