Myeloid Malignancy

Question 1

What are the main myeloid malignancies?

Answer 1

1 - Acute Myeloid Leukaemia

2 - Chronic Myeloid Leukaemia

3 - Myelodysplastic Syndromes

4 - Myeloproliferative Neoplasms

Question 2

What are the key features of acute myeloid leukaemia that differentiate it from chronic myeloid leukaemia?

Answer 2

• Leukaemic cells do not differentiate
• Bone marrow failure
• Rapidly fatal if left untreated
• Potentially curable

Question 3

What are the key features of chronic myeloid leukaemia that differentiate it from acute myeloid leukaemia?

Answer 3

• Leukaemic cells can still differentiate
• Myeloid cells can proliferate without bone marrow failure
• Long term survival possible with modern therapy

Question 4

What are the subgroups of acute leukaemia?

Answer 4

Acute myeloblastic leukaemia

Acute lymphoblastic leukaemia

Question 5

What is the pathophysiology of Acute Myeloblastic Leukaemia?

Answer 5

1 - Myeloblastic cells have a genetic mutation which prevent differentiation into mature myeloid cells

2 - Mutations controlling proliferation occur

3 - The result is uncontrolled growth of immature leukaemic blast cells

Question 6

What are the clinical features of AML?

Answer 6

Bone Marrow failure, resulting in the following:

• Anaemia
• Thrombocytopenic bleeding (purpura and mucosal membrane bleeding)
• Infection due to thrombocytopenia (aspergillosum)

Question 7

What are the essential investigations for AML?

Answer 7

1 - FBC & Blood film

2 - Bone Marrow Aspirate

3 - Cytogenetics

Question 8

How is AML treated?

Answer 8

1) Anti-leukaemic chemotherapy
2) Allogeneic stem cell transplantation
3) Retinoic acid
4) Arsenic Trioxide

Question 9

What antigen do targeted antibody treatments for AML act on?

Answer 9

CD33

Question 10

What are the features of chronic myeloid leukaemia?

Answer 10

1 - Anaemia

2 - Splenomegaly

3 - Weight loss

4 - Hyperleukostasis

Question 11

What chromosome is implicated in chronic myeloid leukaemia?

Answer 11

Philadelphia chromosome

Question 12

What are the features of a CML blood count?

Answer 12

WCC - Very high

Platelets - high

Myeloid cells (e.g. neutrophils, basophils, eosinophils) - High due to proliferation of myeloid cells

Hb - often low

Question 13

Which chromosomes are defected in the philadelphia chromosome implicated in CML?

Answer 13

9 and 22

Question 14

What class of drugs are used to treat CML?

Answer 14

Tyrosine Kinase Inhibitors

Question 15

What is the mode of action of the Tyrosine Kinase Inhibitor drugs?

Answer 15

Inhibit the Philadelphia chromosome pathway (BCR-ABL pathway)

Question 16

What are the common myeloproliferative neoplasms?

Answer 16

Polycythaemia Vera (PV)

Essential Thrombocythaemia (ET)

Idiopathic Myelofibrosis (IM)

Question 17

What is the most common mutation observed in Polycythaemia Vera and Essential Thrombocytopenia?

Answer 17

JAK2V617F

Question 18

What are the clinical features of Polycythaemia Vera?

Answer 18

1 - Headaches

2 -Itch

3 - Vascular Occlusion

4 - Thrombosis

5 - TIA, Stroke

6 - Splenomegaly

Question 19

What are the features of a blood count in Polycythaemia Vera?

Answer 19

1 - Raised Hb conc

2 - Raised Haematocrit

3 - Raised WCC

4 - Raised uric acid

Question 20

How is polycythaemia vera treated?

Answer 20

1 - Keep haematocrit normal

2 - Aspirin

Question 21

What is polycythaemia vera?

Answer 21

Bone marrow makes too many RBC’s

Question 22

What is essential thrombocythaemia?

Answer 22

Myeloproliferative disease

Predominant feature = Raised platelet count