🔬 AML Classification: WHO 5th vs ICC 🩸🧵 1️⃣ WHO 5th Edition: ✅ AML with defining genetic abnormalities (no blast threshold): •🧬 Fusion: RUNX1::RUNX1T1, CBFB::MYH11, DEK::NUP214, BCR::ABL1, etc. •🧬 Rearrangements: KMT2A, MECOM, NUP98 •🧬 Molecular: NPM1, CEBPA ⚠️ If none: ➡️ AML defined by differentiation (blasts ≥20%): •AML M0, M1, M2, M4, M5, M6, M7, etc. 🩺 Separate group: •Post-cytotoxic therapy •Germline predisposition 📄 Ref: •WHO Classification of Haematolymphoid Tumours 5th Ed ⸻ 2️⃣ ICC Classification: ✅ AML with recurrent genetic abnormalities (blasts ≥10%): •RUNX1::RUNX1T1, CBFB::MYH11, DEK::NUP214, NPM1, BCR::ABL1, in-frame bZIP CEBPA ➡️ If no: ✅ AML with TP53 mutation (VAF >10%) ➡️ If no: ✅ AML with myelodysplasia-related gene mutation ➡️ If no: ✅ AML with myelodysplasia-related cytogenetic abnormality ➡️ If no: ✅ AML – NOS ⚠️ Appended qualifiers: •💉 Therapy-related •📈 Prior MDS •📈 Prior MDS/MPN •🧬 Germline predisposition ⚠️ Blast %: •10–19%: MDS/AML •≥20%: AML 📄 Ref: •ICC 2022 Haematological Malignancies Classification ⸻ 🩺 Key takeaways: ✅ ICC lowers blast threshold to 10% if recurrent genetic abnormality present. ✅ WHO retains 20% threshold unless defining genetics. ✅ Emphasis on genetics > morphology. ✅ Clear approach to therapy-related and germline AML. ⸻ 🔗 Save for #Hematology #Boards 🔗 Share with your #Pathology team 🔗 Use during #AML discussions and teaching