Primary Hematopoietic and Lymphoid Tissue ›› Bone Marrow ›› Myeloid ›› Erythroid (RBCs & Precursors) ›› Abnormal
Erythroid Leukemia (AML M6)
›Microscopic Features:
- Marked increase in immature erythroid precursors
- Background of increased erythroid precursors with dysplastic features is also common (Note: the multinucleated erythroid precursor on the left side of the image)
›Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
- PB: None
- BM: None
- LN: None
›May Resemble:
- Myeloblast
- Erythroid hyperplasia
›Differential Diagnoses:
AML (other subtypes)
MDS
MDS
›Classic Immunophenotype:
- Pure Eythroid-type:
- CD34-
- HLADR-
- CD117+/-
- CD235a (Glycophorin A)+
- Hemoglobin A +
- MPO-
- ---------------------------
- Erythroid/Myeloid type
- *Erythroblasts are usually:
- CD235a (Glycophorin A)+
- Hemoglobin A +
- CD71 dim or -
- MPO-
- *Myeloblasts may be:
- CD34+
- CD117+
- MPO-/+
›Cartoon Image:
Click and drag
for direct comparison
for direct comparison
›Misc:
2 types: In "Pure Erythroid"-type (less common) the bone marrow is comprised of 80% or more erythroid precursors while the "Erythroid/Myeloid" type has 50% or more erythroid precursors in the bone marrow with 20% or more myeloblasts (% myeloblasts is calculated in the non-erythroid cells)
Note: As opposed to other AMLs which usually have 20% or more myeloblasts (as calculated from the total number of nucleated cells), in the Erythroid/Myeloid type of AML-M6: %myeloblasts are calculated after subtracting the background erythroid precursors.
Note: As opposed to other AMLs which usually have 20% or more myeloblasts (as calculated from the total number of nucleated cells), in the Erythroid/Myeloid type of AML-M6: %myeloblasts are calculated after subtracting the background erythroid precursors.