WBC Disorders 4

Question 1

Acute Myeloid Leukemia (AML)

Answer 1

acquired oncogenic mutations leading to the accumulation of immature myeloid blasts in the marrow

Older community affected

Risk factors:
• Alkylating chemotherapy
• Radiation
• Myeloproliferative neoplasms like chronic myeloid leukemia (CML) progressing to acute leukemias
• Smoking
• Genetic predisposition with syndromes like Down’s syndrome, Bloom syndrome, Fanconi Anemia, Neurofibromatosis

Question 2

Fab Classification

Answer 2

Question 3

WHO CLASSIFICATION (2017) of AML

Answer 3

1. AML with recurrent genetic abnormalities (including translocations and mutations) (most important!)
2. AML, therapy related
3. AML with myelodysplasia like features
4. AML, not otherwise specified

Question 4

Classification of myeloid neoplasms

Answer 4

Immature

• acute in onset
• Acute myeloid leukemia
• Classified according to type of blasts/ immature cells increased

Mature

• chronic in onset
• myeloid-proliferating neoplasms (MPN)
• Classified according to type of mature cells increased
• Can undergo blast transformation or marrow fibrosis

Defectively mature

• myelo-dysplastic syndrome
• Characterized by peripheral blood cytopenias due to marrow dysplasias

Question 5

Morphological features of acute myeloid leukemia

Answer 5

• Blasts of myeloid lineage in bone marrow and/or peripheral blood >20%- AML

Myeloblasts: delicate nuclear chromatin, moderate cytoplasm with Myeloperoxidase and Sudan Black B positive granules, auer rods, 2-4 prominent nucleoli

Promyelocytes: numerous azurophilic granules and a lot of auer rods

Question 6

AML M3 - ACUTE PROMYELOCYTIC LEUKEMIA

Answer 6

• Hypergranular promyelocytes with multiple Auer rods
• Classified non inflammatory as AML with t(15;17) which leads to fusion of PML and RARA genes blocking maturation of promyelocyte to myelocyte
• Fusion oncoprotein targeted by All trans retinoic acid (ATRA) and arsenic salts→promotes maturation→excellent prognosis
• Abnormal granules which are procoagulant- risk of DIC

Question 7

AML M5 (and M4 less frequently)

Answer 7

monoblasts infiltrate gums and cause gum hypertrophy

Question 8

AML M7

Answer 8

Associated with down syndrome

Question 9

AML with ______ and _______ are good prognosis

Answer 9

AML with t(8;21) and inversion 16- good prognosis

Question 10

AML with ______ causes - poor prognosis

Answer 10

AML with deletions of chromosome 5q- poor prognosis

Question 11

Clinical features of AML

Answer 11