Diagnostic Steps for Acute Myeloid Leukemia (AML)
Initial Diagnostic Workup
- The American Society of Clinical Oncology recommends obtaining comprehensive medical history including any history of possibly confounding factors such as recent growth factor therapy, transfusions, or medications that might obscure or mimic features of acute leukemia 1
- Document family history of hematologic disorders or other malignancies 1
- Provide relevant physical examination findings including neurologic examination and presence of tumor masses, cutaneous lesions, or organomegaly 1
- Review complete blood count (CBC) with platelets and white blood cell differential 1, 4
- Evaluate peripheral blood smear for morphologic assessment 1, 2
Bone Marrow Examination
- Obtain fresh bone marrow aspirate for all patients suspected of AML 1
- Prepare bone marrow aspirate smears for morphologic evaluation 1
- Evaluate bone marrow trephine core biopsy, trephine touch preparations, and/or marrow clots in conjunction with aspirates 1, 2
Essential Diagnostic Studies
- Perform conventional cytogenetic analysis (karyotype) 1, 4
- Conduct flow cytometry immunophenotyping with a panel sufficient to distinguish AML, including early T-ALL, B-ALL, and AL of ambiguous lineage 1, 5
- Perform appropriate molecular genetic and/or FISH testing 1, 4
Molecular and Genetic Testing
- Test for FLT3-ITD in all patients with suspected or confirmed AML 5
- For CBF AML (with t(8;21) or inv(16)/t(16;16)), ensure KIT mutation analysis 5
- For suspected APL, perform rapid detection of PML-RARA 5
- For non-CBF AML, non-APL cases, perform mutational analysis for NPM1, CEBPA, and RUNX1 5
Risk Assessment and Classification
- Age of the patient (>60 years associated with adverse prognosis) 2, 3
- Initial leukocyte count 2, 3
- Cytogenetic abnormalities (favorable: t(15;17), t(8;21), inv(16)) 2, 3
- Molecular mutations (NPM1, FLT3-ITD, CEBPA, etc.) 4, 5
Special Considerations
- If extramedullary disease is suspected, perform PET/CT 4
- For patients with significant CNS signs or symptoms, evaluate using appropriate imaging (radiography, CT, or MRI) 4
- For extramedullary disease without bone marrow or blood involvement, evaluate tissue biopsy specimen with the same workup as recommended for bone marrow 5
Quality Control
- Ensure all laboratory testing is performed in laboratories compliant with regulatory requirements 5
- Ideally, the same physician should interpret both bone marrow aspirate smears and core biopsy specimens 1