Myeloproliferative disorders (zero to finals)

Question 1

What are myeloproliferative disorders?

Answer 1

Myeloproliferative disorders involve the uncontrolled proliferation of a single type of stem cell.

Question 2

Myeloproliferative disorders usually develop and progress quite quickly. True/false?

Answer 2

False

They are considered a form of cancer occurring in the bone marrow, although they tend to develop and progress slowly.

Question 3

What can these myeloproliferative disorders transform into as a complication?

Answer 3

AML (acute myeloid leukaemia)

Question 4

What are the 3 main myeloproliferative disorders?

Answer 4

Polycythaemia vera

Primary myelofibrosis

Essential thrombocythaemia

Question 5

What is the proliferating cell line in primary myelofibrosis?

Answer 5

Haematopoietic stem cells

Question 6

What is the blood finding in primary myelofibrosis?

Answer 6

Low haemoglobin

High or low white cell count

High or low platelet count

Question 7

What is the proliferating cell line in polycythemia vera?

Answer 7

Erythroid cells aka erythrocytes (RBC’s)

Question 8

What is the blood finding in polycythemia vera?

Answer 8

High haemoglobin

Question 9

What is the proliferating cell line in essential thrombocythemia?

Answer 9

Megakaryocytes (precursor platelet cells)

Question 10

What is the blood finding in essential thrombocythemia?

Answer 10

High platelets

Question 11

What are the 3 main mutations occurring in myeloproliferative disorders?

Answer 11

JAK2 (main one) - treatment is with JAK2 inhibitors i.e. ruxolitinib

MPL

CALR

Question 12

Which of the myeloproliferative disorders can cause myelofibrosis?

Answer 12

Any of the 3

Myelofibrosis can result from primary myelofibrosis, polycythaemia vera or essential thrombocythaemia.

Question 13

What is myelofibrosis?

Answer 13

Myelofibrosis is where the proliferation of a single cell line leads to bone marrow fibrosis, where bone marrow is replaced by scar tissue.

Question 14

How does fibrosis of the bone marrow affect blood cell production?

Answer 14

Fibrosis affects the production of blood cells and can lead to low haemoglobin (anaemia), low white blood cells (leukopenia) and low platelets (thrombocytopenia).

Question 15

What happens as a result of fibrosis to the bone marrow?

Answer 15

When the bone marrow is replaced with scar tissue, the production of blood cells (haematopoiesis) starts to happen in other areas, known as extramedullary haematopoiesis.

Production of blood cells in the liver and spleen causes hepatomegaly, splenomegaly, and portal hypertension.

When it occurs around the spine, it can cause spinal cord compression.

Question 16

What can a blood film show for myelofibrosis?

Answer 16

Teardrop-shaped red blood cells

Anisocytosis (varying sizes of red blood cells)

Blasts (immature red and white cells)

Question 17

What are the non-specific symptoms of myeloproliferative disorders?

Answer 17

Fatigue

Weight loss

Night sweats

Fever

Question 18

What are the potential signs and symptoms of underlying conditions relating to myeloproliferative disorders?

Answer 18

Anaemia (tiredness, shortness of breath and dizziness)

Splenomegaly (abdominal pain)

Portal hypertension (ascites, varices and abdominal pain)

Low platelets (bleeding and petechiae)

Raised haemoglobin (itching, headaches and a red face)

Low white blood cells (infections)

Gout is a complication of polycythaemia

Question 19

What is a common complication of polycythemia (high red cell in blood) and thrombocythemia (high platelets in blood)?

Answer 19

Thrombosis is a common complication of polycythaemia and thrombocythaemia, leading to myocardial infarction, stroke or venous thromboembolism (e.g., DVT and PE).

Question 20

What are common signs of polycythemia?

Answer 20

Ruddy complexion (red face)

Conjunctival plethora (the opposite of conjunctival pallor)

Splenomegaly

Hypertension

Question 21

How are myeloproliferative disorders diagnosed?

Answer 21

Bone marrow biopsy is required to confirm the diagnosis.

Bone marrow aspiration may be “dry” with myelofibrosis, as the bone marrow has turned to scar tissue.

Testing for the JAK2, MPL and CALR genes can help with diagnosis and management.

Question 22

Management of primary myelofibrosis?

Answer 22

No active treatment for mild disease with minimal symptoms

Supportive management of complications, such as anaemia, splenomegaly and portal hypertension

Chemotherapy (e.g., hydroxycarbamide) to help control the disease

Targeted therapies, such as JAK2 inhibitors (ruxolitinib)

Allogeneic stem cell transplantation (risky but potentially curative)

Question 23

Management of polycythemia vera?

Answer 23

Venesection to keep the haemoglobin in the normal range

Aspirin to reduce the risk of thrombus formation

Chemotherapy (typically hydroxycarbamide) to help control the disease

Question 24

Management of essential thrombocythemia?

Answer 24

Aspirin to reduce the risk of thrombus formation

Chemotherapy (typically hydroxycarbamide) to help control the disease

Anagrelide is a specialist platelet-lowering agent

Question 25

What bone marrow changes occur in myelofibrosis?

Answer 25

In myelofibrosis, the bone marrow undergoes fibrosis, which means that fibrous tissue gradually replaces the normal bone marrow cells.

This fibrosis impairs the bone marrow’s ability to produce normal blood cells, including red blood cells, white blood cells, and platelets.

Question 26

Clinical features of myelofibrosis?

Answer 26

Fatigue, weakness, shortness of breath, easy bruising or bleeding, and an enlarged spleen (splenomegaly).

Question 27

Complications of myelofibrosis?

Answer 27

Myelofibrosis can lead to complications such as anemia, infections, bleeding disorders, and enlargement of the spleen (splenomegaly).

In some cases, myelofibrosis may progress to acute myeloid leukaemia, a more aggressive type of blood cancer.

Question 28

What could be a cause of myelofibrosis?

Answer 28

Myelofibrosis may develop as a progression of other myeloproliferative neoplasms, such as polycythaemia vera or essential thrombocythaemia.

Question 29

What is treatment for myelofibrosis?

Answer 29

Focuses on managing symptoms, reducing complications, and improving quality of life.

Therapeutic options may include medications to alleviate symptoms (such as anaemia or enlarged spleen), blood transfusions, chemotherapy, targeted therapy, and stem cell transplantation in select cases.