Acute Myeloid Leukemias

What are acute leukemias?

Stem cell disorders characterized by malignant neoplastic proliferation and accumulation of immature and nonfunctional hematopoietic cells in the bm

What cells are affected by AMLs?

CFU-GEMM, CFU-GM, CFU-E

What percentage of blasts must be present to distinguish an AML from MDS?

>20%

Explain the FAB classification 

Classifies AML purely by morphology with a >30% blast cutoff

Explain the WHO classification

Classifies AML by incorporating genetics, molecular mutations, clinical features, and lowers AML blast threshold to >20% and defines AML based on specific cytogenetic lesions

The FAB classification of AMLs are based on bone marrow morphology. What is the normal M:E ratio?

2:1 to 4:1

In AML, the myeloid cells outnumber the nucleated erythroid with a high blast count. Again what are nucleated erythroids?

Pronormoblast, basophilic normoblast, polychromatic normoblast, etc…

What AML instead has erythroid precursors outnumbering the myeloid cells with a high blast count?

AML M6

What AML is described as myeloblasts without granules where auer rods can be present?

• myeloperoxidase stain: neg

• sudan black: neg

• specific esterase: neg

• nonspecific esterase: neg

Acute Myeloblastic Leukemia AML M0; minimally differentiated

What AML is described as myeloblasts with or without granules where auer rods can be present?

• myeloperoxidase: pos

• sudan black: pos

Acute Myeloblastic Leukemia AML M1; minimal mature

What AML is described as myeloblasts with granules with a few pro and myelocytes? Blasts still dominate tho for sure.

• myeloperoxidase: pos

• sudan black: pos

Acute Myeloblastic Leukemia AML M2 with maturation

What AML is dominated by abnormal promyelocytes with auer rods being common (faggot cells)?

• myeloperoxidase: pos

• sudan black: pos

• specific esterase: pos

• nonspecific esterase: neg

Acute Promyelocytic Leukemia AML M3 

What AML is dominated by both myeloid and monocytic cells?

• myeloperoxidase: pos

• sudan black: pos

• specific esterase: pos

• nonspecific esterase: pos

Acute Myelomonocytic Leukemia AML M4

What AML is dominated by monocytic cells?

• myeloperoxidase: neg

• sudan black: neg

• specific esterase: neg

• nonspecific esterase: pos

Acute Monoblastic Leukemia AML M5

What AML is dominated by erythroid precursors with myeloblasts?

• myeloperoxidase: pos

• sudan black: pos

• periodic acid schiff (PAS): pos

Acute Erythroleukemia AML M6 

What AML is dominated by Megakaryoblasts?

• myeloperoxidase: neg

• sudan black: neg

Acute megakaryoblastic leukemia AML M7