FAB Classification of AML-5
M6:
Erythroleukemia 3% of AML cases
>50%
of marrow nucleated cells are nRBCs
Hyperplasia
of erythroid precursorsin bm (M:E <1)
30%
of nRBCs in bone marrow are myeloblasts
PAS
stain is positive with “block” pattern in early stages
and diffuse pattern in more mature cells
Ringed
sideroblasts may be seen
Myelodysplastic
syndrome may precede M6 and is called “erythemic myelosis”:
Progressive
anemia
Erythroid
hyperplasia of bone marrow
<30%
blasts
Ringed
sideroblasts may be seen
Prominent
peripheral basophilic stippling