Page 168 - Clinical Hematology Atlas

152 SECTION FOUR LEUKOCYTES

ACUTE PROMYELOCYTIC LEUKEMIA

B

B
A

A B
FIGURE 15–4A Peripheral blood. A, Hypergranular FIGURE 15–4B Bone marrow (3500).
promyelocyte (31000); B, Faggot cells.

MORPHOLOGY
Peripheral Blood: White blood cell count may be
low or only slightly elevated
Blasts, hypergranular promyelocytes, cytoplasm
gray to blue, nucleus may be folded or bilobed
Multiple Auer rods possible, may be in bundles
(Faggot cells), schistocytes

Bone Marrow: Blasts, hypergranular promyelocytes,
nuclei often bilobed or kidney shaped
6 Multiple Auer rods
CYTOCHEMISTRY
Myeloperoxidase: strongly positive (see Figure 15-2, E)
Sudan Black B: strongly positive (see Figure 15-2, F)
GENETICS
C t(15;17) is sufficient for diagnosis as AML with
FIGURE 15–4C Bone marrow (31000). recurrent genetic abnormalities regardless of blast/
promyelocyte count. ‡
IMMUNOPHENOTYPE
CD13 , CD33 , CD34 , HLA-DR 2
6
2
1
‡ 1. Abnormal promyelocytes are considered blast equivalents for the purpose of diagnosis.
2. May be associated with disseminated intravascular coagulopathy.