Acute Leukemia

Question 1

How is acute leukemia defined?

Answer 1

Accumulation of >20% of blasts in the bone marrow

Question 2

What is the normal percentage of blasts?

Answer 2

~ 1-2%

Question 3

How is does acute leukemia present?

Answer 3

• Results in acute/sudden presentation w. anemia (RBCs), thrombocytopenia (bleeding), neutropenia (infection)
• High WBCs

Question 4

What do blasts look like on blood smear?

Answer 4

Large, w. punched out nucluei (nucleolus)

- Small cytoplasm

Question 5

How can you differentiate between Myeloblasts and lymphoblasts?

Answer 5

Lymphoblast
- tdt +ve in nucleus

Myeloblasts

• MPO (myeloperoxidase) in cytoplasm
• Can crystalise into AUer rods

Question 6

What is TdT?

Answer 6

DNA polymerase

- In nucleus of lymphoblasts

Question 7

When is ALL associated with Downs Syndrome?

Answer 7

After the age of 5

Question 8

What is the most common type of ALL?

Answer 8

B-ALL

Question 9

What do the lymphoblasts classically express in B-ALL?

Answer 9

CD10, CD19, CD20

Question 10

What areas require prophylactic chemotherapy in ALL?

Answer 10

Scrotum and CSF

Question 11

What are the cytogenic abnormalities in B-ALL?

Answer 11

• t(12;21) - good prognosis - more commonly seen in kids

- t(9;22) has a poor prognosis - more commonly seen in adults

Question 12

What is T-ALL also known as

Answer 12

Acute lymphoblastic lymphoma

Question 13

What does T-ALL (Acute lymphoblastic lymphoma) present as?

Answer 13

Mediastinal (thymic) mass in teenager

Question 14

What ages are usually affected by AML?

Answer 14

50-60

Question 15

How can AML be subclassified?

Answer 15

• Cytogenetic abnormalities
• Lineage of myeloblasts
• Surface markers

Question 16

What translocation is present in Acute promyelocytic leukemia?

Answer 16

t(15;17)

Question 17

Describe Acute promyelocytic leukemia (15;17)?

Answer 17

• RAR (retinoic acid receptor) receptor disrupted; promyelocytes accumulates
• Promyelocytes contain numerous Auer rods; risk for DIC
• ATRA causes blasts to mature

Question 18

What can Auer rods cause?

Answer 18

DIC

- May activate coagulation cascade

Question 19

What are patients given in Acute promeyelotic leukemia?

Answer 19

ATRA

- Causes blasts to mature

Question 20

What is characteristic of acute monocytic leukemia?

Answer 20

• Proliferation of monoblasts; lack MPO

- Blasts characteristically infiltrate gums

Question 21

What is acute megakaryoblastic leukemia associated with / characterised by?

Answer 21

• Lack of MPO

- Down syndrome after age of 5

Question 22

What is the classic circumstance by which AML can arise from pre-existing dysplasia?

Answer 22

Prior exposure to alkylating agents or radiotherapy

Question 23

What is seen in myelodysplastic syndromes?

Answer 23

• Cytopenias with hypercellular bone marrow
• Abnormal maturation with increased blasts (<20%)
• Most patients die from infection or bleeding
• May progress to Acute leukemia (>20% blasts)