16. Introduction to Leukemia and the Acute Leukemias

Question 1

1.A 4-year-old boy presents with bruising,fever,and coughing. His white blood cell count is 15 x 10°/L;hematocrit, 23%; and platelets, 53 x 10°/L. A bone mar-row aspirate is obtained that reveals sheets of immature cells. Cytochemical studies for peroxidase and NSE are negative; the TdT is positive, Surface markers studies are done that show the following phenotype; HLA-DR+; CD19+;;CD19+;CD10+;Cμ-;Cμ-;sIg-;CD7-.A portion of the aspirate is sent for cytogenetics and molecular studies. What is the most likely diagnosis?
a.AML
b.Precursor-B-cell ALL with t(9;22) BCR-ABL
c.Precursor-B-cell ALL with t(12;21) TEL-AML1
d.T-cell ALL

Answer 1

c.Precursor-B-cell ALL with t(12;21) TEL-AML1

Question 2

2.A 42-year-old woman present with an elevated white blood cell count, anemia and thrombocytopenia. The white blood cell count is 50 x 10°/L with 80% blasts,15% segmented neutrophils, and 5% lymphocytes. The bone marrow reveals sheets of immature cells. Cyto-chemical studies show MPO positive (20%) and the non-specific esterase negative staining on the immature cells.Flow cytometry shows the biast population positive for CD13, CD33, dim CD45, CD34, and CD117.What is the diagnosis?

a.AML, without maturation, FAB MI type
b.AML, with maturation,FAB M2 type
c.AML,acute myelomonocytic leukemia, FAB M4 type
d. AML, acute monoblastic leukemia, FAB M5type

Answer 2

a.AML, without maturation, FAB MI type

Question 3

3. The white blood cell count is 15 x 10°/L with 90%blasts, 6% segmented neutrophils, and 4% monocytes.The blasts are relatively large and have abundant cyto-plasm. More than 90% of them are positive with the nonspecific esterase stain, and an occasional blast is pos-itive with Sudan black. What is the diagnosis?
   a.AML, with maturation, FAB M2 type
   b.AML, acute promyelocytic leukemia, FAB M3 type
   c.AML, acute myelomonocytic leukemia, FAB M4 type
   d.AML, acute monoblastic leukemia, FAB M5 type

Answer 3

d.AML, acute monoblastic leukemia, FAB M5 type

Question 4

4.Cytochemical stains were performed on bone marrow smears from an acute leukemia patient. All blasts were TdT negative.The majority of the blasts showed varying amounts of Sudan black B positivity. Fifty percent of them stained positive for nonspecific esterase. What type of leukemia is indicated?
a. Acute myeloblastic leukemia
b.ALL
c. Acute myelomonocytic leukemia
d.Acute erythroleukemia

Answer 4

c. Acute myelomonocytic leukemia

Question 5

5. Bone marrow examination reveals a hypercellular mar-row with 60% blasts. Flow cytometry shows the follow-ing blast immunophenotype:CD3,CD7,CD10,CD13,CD34, CD45,and TdT positive. Surface immunoglobins are negative. The diagnosis is:
   a. Burkitt’s leukemia
   b.AML
   c.ALL,precursor B-cell type
   d.ALL, precursor T-cell type

Answer 5

d.ALL, precursor T-cell type

Question 6

6. A 49-year-old woman was admitted to the hospital for easy bruising and menorrhagia. She had evidence of dis-seminated intravascular coagulation.Her white blood cell count is 3 x 10°/L with 95% large, atypical mononuclear cells and some atypical bilobed cells. Many of these cells are packed with larger, purple-staining granules; some have multiple Auer rods; and all are strongly peroxidase-positive. What is the diagnosis?
   a.AML,FAB M2
   b.AML, FAB M3
   c.AML, FAB M4
   d.AML,FAB M5

Answer 6

b.AML, FAB M3

Question 7

7.What is the likely genetic abnormality referring to ques-tion 6?
a. t(8;21)AMLI-ETO
b. t(4;11)AF4-MLL
c.t(9;22) BCR-ABL
d. t(15;17)PML-RARα

Answer 7

d. t(15;17)PML-RARα

Question 8

8. A 21-year-old patient’s bone marrow and peripheral blood has medium sized blasts with basophilic cyto-plasm and numerous lipid vacuoles. Cytogenetic studies show t(8;14) involving MYC on chromosome 8 and the Ig heavy chain region on chromosome 14. Flow cytome-try is most likely to show which of the following?
   a. CD3,CD7,CD10,CD45,and TdT
   b.CD10, CD19,CD20, CD45, and surface k light chain
   c. CD10,CD19,CD45,TdT,and surface k light chain
   d. CD10,CD19,CD34,and no surface light chain or TdT

Answer 8

b.CD10, CD19,CD20, CD45, and surface k light chain

Question 9

9.Which of the following is true about the prognostic implications of cytogenetic findings seen in precursor
B-cell ALL?
a. Hypodiploidy as determined by flow cytometry DI is associated with a favorable prognosis
b. t(1;19) PBX-E2A is associated with an unfavorable prognosis
c. t(9;22)BCR-ABL is associated with a favorable prognosis
d. Hyperdiploidy of greater than 50 chromosomes as determined by flow cytometry DI is associated with a poor prognosis.

Answer 9

b. t(1;19) PBX-E2A is associated with an unfavorable prognosis

Question 10

10.What cytochemical stain is best for differentiating AML from ALL?
a.Alpha-naphthyl acetate
b.Nonspecific esterase
c.Myeloperoxidase
d.Periodic acid-Schiff

Answer 10

c.Myeloperoxidase

Question 11

11. How many blast cells in a bone marrow aspirate smear are necessary for a diagnosis of acute leukemia using FAB criteria?
    a.20%
    b.15%
    c.25%
    d.30%

Answer 11

d.30%

Question 12

12. How many blast cells in a bone marrow aspirate smear are necessary for a diagnosis of acute leukemia using WHO criteria?
    a.20%
    b.15%
    c.25%
    d.30%

Answer 12

a.20%

Question 13

13.Which chromosome abnormality occurs in the FAB M2type of AML?
a.t(8;21)
b. t(9;22)
c.t(15;17)
d.t(1;19)

Answer 13

a.t(8;21)

Question 14

14. Which cytochemical stain is useful in separating myeloblasts from monoblasts?
    a. Myeloperoxidase
    b. Sudan black B
    c. Specific esterase
    d.Nonspecific esterase

Answer 14

d.Nonspecific esterase

Question 15

15. Which chromosome abnormality occurs in the FAB M3type of AML?
    a.t(8;21)
    b.t(9;22)
    c.t(15;17)
    d.t(1;19)

Answer 15

c.t(15;17)