AIM Step 10
3rd Year MBBS
Blood & Immunology
3rd Year MBBS
Blood & Immunology
Student Memory Support
Topic 3 — Myeloid Neoplasms, Myelodysplastic Syndromes and Myeloproliferative Disorders
High-yield memory reinforcement and last-minute KMU revision. :contentReference[oaicite:0]{index=0}
1. High-Yield Flashcards
Tap each question to reveal the answer.
What is the basic pathological defect in acute myeloid leukemia?
Clonal myeloid proliferation with impaired differentiation, causing accumulation of myeloblasts.
Which FAB subtype corresponds to acute promyelocytic leukemia?
M3.
What cytoplasmic finding strongly supports myeloid differentiation in AML?
Auer rods.
Why do patients with AML develop anemia, infections and bleeding?
Leukemic blasts suppress and replace normal bone-marrow hematopoiesis.
What molecular abnormality drives chronic myeloid leukemia?
BCR::ABL1 fusion produced by t(9;22).
What peripheral-blood pattern is typical of chronic-phase CML?
Marked leukocytosis with granulocytes at multiple maturation stages and basophilia.
What is the major treatment principle in CML?
Target BCR::ABL1 tyrosine kinase with an inhibitor such as imatinib.
What is the central hematological defect in myelodysplastic syndromes?
Clonal dysplastic and ineffective hematopoiesis causing peripheral cytopenias.
Why can MDS cause cytopenias despite a hypercellular marrow?
Abnormal precursors mature ineffectively and many are lost within the marrow before entering blood.
What neutrophil abnormality is a useful morphological clue in MDS?
Pseudo-Pelger-Huët hyposegmentation.
What important malignant outcome may develop from MDS?
Progression to acute myeloid leukemia.
What signaling abnormality is strongly associated with polycythemia vera?
Activating JAK2-pathway abnormality.
What bone-marrow pattern is characteristic of polycythemia vera?
Panmyelosis involving erythroid, granulocytic and megakaryocytic lineages.
What serum erythropoietin pattern supports polycythemia vera?
Reduced serum erythropoietin.
How do G-CSF and GM-CSF differ in hematopoietic stimulation?
G-CSF mainly increases neutrophils; GM-CSF stimulates granulocyte and monocyte progenitors more broadly.
2. Mnemonics
Mnemonic Title: FAB AML Differentiation
“Pro–Myelo–Mono–Ery–Mega”
Meaning: M3 Promyelocytic → M4 Myelomonocytic → M5 Monocytic → M6 Erythroid → M7 Megakaryoblastic.
Mnemonic Title: CML Core Chain
“9–22 → BCR → TKI”
Meaning: t(9;22) produces BCR::ABL1 tyrosine kinase, which is targeted by tyrosine-kinase inhibitors.
Mnemonic Title: Polycythemia Vera Diagnostic Links
“J-P-E”
Meaning: JAK2 activation → Panmyelosis → low Erythropoietin supports polycythemia vera.
3. Memory Tables
Myeloid Disorders — Rapid Differentiation
| Feature | AML | CML | MDS | PV |
|---|---|---|---|---|
| Main defect | Blast accumulation | Granulocytic proliferation | Ineffective dysplasia | Autonomous panmyelosis |
| Key clue | Blasts ± Auer rods | Maturation spectrum + basophilia | Cytopenia + dysplasia | Erythrocytosis |
| Important test | Marrow + lineage studies | BCR::ABL1 | Marrow dysplasia/blasts | JAK2 + low EPO |
| Major outcome | Marrow failure | Advanced/blast phase | Progression to AML | Thrombosis / fibrosis |
G-CSF versus GM-CSF
| Feature | G-CSF | GM-CSF |
|---|---|---|
| Prototype | Filgrastim | Sargramostim |
| Main target | Neutrophil precursors | Broader myeloid progenitors |
| Main result | Neutrophil recovery | Granulocyte + monocyte recovery |
4. Rapid Revision Points — Last-Minute Revision
Must Remember:
- AML is a disease of abnormal myeloid blasts with impaired maturation.
- FAB M3 is acute promyelocytic leukemia; M7 is acute megakaryoblastic leukemia.
- Auer rods support myeloid differentiation.
- CML is driven by BCR::ABL1 from t(9;22).
- Chronic-phase CML shows granulocytes at several stages of maturation rather than only blasts.
- MDS may have a hypercellular marrow but low peripheral blood counts because hematopoiesis is ineffective.
- Pseudo-Pelger-Huët cells and ring sideroblasts are important dysplastic clues in MDS.
- Polycythemia vera is a clonal myeloproliferative neoplasm associated with JAK2 activation and panmyelosis.
- Low erythropoietin favors polycythemia vera over many forms of secondary erythrocytosis.
- Filgrastim stimulates neutrophil production and may cause bone pain from increased marrow activity.
KMU Exam Trap: A high total leukocyte count does not automatically mean acute leukemia; chronic-phase CML contains many maturing granulocytic forms, while AML is defined by abnormal blast proliferation.
5. Clinical Memory Hooks
Fatigue + infections + bleeding + circulating blasts →
marrow failure from acute leukemia; consider AML when myeloid differentiation is demonstrated.
marrow failure from acute leukemia; consider AML when myeloid differentiation is demonstrated.
Massive leukocytosis + splenomegaly + maturing granulocytes →
think CML and confirm BCR::ABL1.
think CML and confirm BCR::ABL1.
Older patient + cytopenias + cellular dysplastic marrow →
ineffective hematopoiesis suggests MDS.
ineffective hematopoiesis suggests MDS.
Plethora + headache + erythrocytosis + splenomegaly →
consider polycythemia vera; JAK2 evidence and low erythropoietin support the diagnosis.
consider polycythemia vera; JAK2 evidence and low erythropoietin support the diagnosis.
6. Starred High-Yield Exam Points
- ⭐ Auer rods: strong morphological evidence of myeloid differentiation in AML.
- ⭐ Acute promyelocytic leukemia: FAB M3 and characteristically associated with PML::RARA.
- ⭐ CML molecular hallmark: BCR::ABL1 fusion due to t(9;22).
- ⭐ CML treatment prototype: imatinib inhibits BCR::ABL1 tyrosine kinase.
- ⭐ MDS paradox: hypercellular marrow can coexist with peripheral cytopenias because hematopoiesis is ineffective.
- ⭐ Polycythemia vera: JAK2-driven panmyelosis with reduced erythropoietin supports autonomous red-cell production.
- ⭐ Filgrastim: G-CSF that promotes neutrophil recovery; characteristic adverse effect is bone pain.