Page 175 - Clinical Hematology Atlas

CHAPTER 15 ACUTE MYELOID LEUKEMIA 159

MORPHOLOGY
Peripheral Blood: Monoblasts, promonocytes
Bone Marrow: Monoblasts large with abundant, moderate basophilic cytoplasm, some with
folded nuclei, one or more prominent nucleoli
Promonocytes, irregular, convoluted nucleus, cytoplasm slightly basophilic; granules;
occasional vacuoles
$80% have monocytic morphology
Granulocytic component ,20%
NOTE: Monoblastic leukemia is diagnosed when $80% leukemic cells are monoblasts. Mono-
cytic leukemia predominant cell type is promonocytes.
CYTOCHEMISTRY
Myeloperoxidase: negative
Nonspecific Esterase: positive (see Figures 15-6, E, and 15-8, D)
GENETICS
Subset with t(9;11)(p22;q23);MLLT3-MLL is diagnosed as AML with recurrent genetic
abnormalities.
IMMUNOPHENOTYPE
CD33 , CD13 , CD4 , CD14 , CD11b , CD64 , CD15 , CD65 , CD11c , CD36 ,
1
1
1
1
1
1
1
1
1
1
CD68 , HLA-DR 1
1