Stains, Malignant disorders of leukocytes: AML

Question 1

What %age of circulating blasts establishes diagnosis of AML?

Answer 1

>/=20%

Question 2

What cytochemical stains can be useful in initial eval of a suspected AML?

Answer 2

MPO, specific esterase usually positive in granulocytic cells and negative in lymphoid/monocytic

Question 3

What is NONspecific esterase usually positive in? what is the stain composed of?

Answer 3

nonspecific esterase usually positive in monoblasts and megakaryoblasts; Stain is alpha-naphthyl acetate or butyrate

Question 4

what is the specific esterase stain also referred to as?

Answer 4

chloroacetate

Question 5

what does the PAS stain, and what is it helpful to daignose?

Answer 5

intracellular glycoge stains bright pink; it is not used much anymore but cells of erythroleukemia will stain (normal RBCs won’t) and Accute lymphoblastic leukemia. Myeloblasts and normal erythro cells don’t stain

Question 6

what does the LAP stain and what will be high or low, condition-wise?

Answer 6

it stains the primary granules of neutrophils that have alkaline phosphatase activity; In CML it will be a lower score; will be higher in a leukemoid reaction, or CML in blast crisis

Question 7

What does the TRAP stain identify and how?

Answer 7

Hairy cell leukemia; It continues to stain positive whereas normal cells will be inhibited once tartrate is added

Question 8

what are iron inclusions named depending on the stain used?

Answer 8

With Perl’s Prussian blue they are called siderotic granules; with Wright’s stain just Pappenheimer bodies

Question 9

What conditions are ringed sideroblasts potentially a sign of?

Answer 9

could be sideroblastic anemia, or refractory anemia with ringed sideroblasts (RARS)

Question 10

what translocation is associated with a FAB morphology like M2, myelogenous with some maturation: blasts with sometimes large azurophilic granules, some auer rods; CD13, CD34, HLA-DR and especially CD19 & CD56 positive?

Answer 10

t(8;21)

Question 11

What genetic abnormality may be associated with an AML of M4eo (has dysplastic eosinophils, and myelomonocytic differentiation); pos for CD14, CD64, CD11b…..

Answer 11

inv 16 or t(16;16)

Question 12

t(15;17) is associated with what type of AML? how does it often present?

Answer 12

APL, M3;

often presents with DIC; can be hypergranular or hypogranular.

Hypergranular is typical and has bundles of auer rods and intense granules (remember these are PROmyelocytes).

Agranular is just that, and may have kidney shaped nuclei in the promyelocytes.

Question 13

In leukemia with t(15;17)/ M3, what promyelocytic CD marker is unusually weak (normal pros it is veyr bright?)

Answer 13

CD15

Question 14

what is the usual agent used to treat AML w/ t(15;17)/ M3?

Answer 14

ATRA, all trans retinoic acid

Question 15

what FAB classification may include t(9;11) and is common in children; and what particular section of the gene is found in many leukemias and has poor prognosis?

Answer 15

M4 or M5, having monoblastic maturation (CD14, CD64); gene 11 arm q loci 23…..11q23 aberrations

Question 16

quick associations: give the genetic abnormality and/or FAB associated with:

Promyelocytic differentiation of abnormal cells, hypergranular with auer rods or hypogranular and kidney-shaped nuclei; Often presents with DIC

Answer 16

FAB M3, APL; t(15;17)

Question 17

quick association: genetic trnslctn and FAB associated with:

an acute myelogenous leukemia with some differentiation, auer rods present, most common CD13 and CD33 positive;

Answer 17

t(8;21)/ M2

Question 18

what would be the origin of a leukemic cell if it is MPO, SBB, and specific (chloroacetate) esterase positive?

Answer 18

myeloid precursor

Question 19

the CD markers associated with myeloid cells (pan) are:

Answer 19

CD13 and CD33

Question 20

what does CD34 signify and how is it used to evaluate WBCs?

Answer 20

It is a stem cell/ hematopoietic cell marker, used to identify them for stem cell transplant cell dosing

Question 21

what translocation should you think of : AML FAB M4Eo (increased dysplastic eosinophils)

Answer 21

t(16;16) or inv16

Question 22

quick association: t(9;11), CD34 negative

Answer 22

M4 or M5, monoblastic differentiation, common in children

Question 23

11q23

Answer 23

poor prognosis, M5 monocytic precursors

Question 24

t(9;22)

Answer 24

CML, philadelphia chromosome

Question 25

what are these cell markers indicative of and in what leukemia would you find?

CD41, 42, AND 61

Answer 25

PLATELETS; FAB M7, acute megakaryocytic, very rare

Question 26

the WHO classification of AMLs all have what percentage of blasts?

Answer 26

>/= 20% in bone marrow

(FAB was 30%)

Question 27

what type of differentiation/ leukemia is FAB M6?

Answer 27

erythroleukemia aka DiGuglielmo syndrome.

Question 28

How is DiGuglielomo syndrome/ Erythroleukemia characterized and what stains are positive?

Answer 28

>20% (WHO) marrow myeloblasts and >50% dysplastic normoblasts (erythrocytic!)

malignant normoblasts are PAS +

malignant myelos are MPO and SBB +

Question 29

FAB M1 & M2 account for what %age of the AMLs?

Answer 29

50%

Question 30

what FAB classification has blasts with myeloid markers of CD13, 33 and 34 (HSC) but stains negatively with MPO, SBB….

Answer 30

M0

Question 31

CD 45 is a cell marker for what group?

Answer 31

all leukocytes/WBCs. Used in flow

Question 32

differentiate monocytic vs myelocytic/granulocyte cells based on esterase staining

Answer 32

the specific esterase stain, (naphthol AS-D chloroacetate esterase) is positive in granulocytic but not cells with monocytic cells;

the nonspecific esterase stain is only positive in monocytic cells