myeloproliferative disorders

Question 1

what are the 3 myeloproliferative disorders?

Answer 1

Primary myelofibrosis- haematopoetic stem cell line

Polycythaemia vera- erythroid cells

Essential thrombocythaemia- megakaryocytes

Question 2

which cancer can myeloproliferative disorders progress to?

Answer 2

acute myeloid leukaemia

Question 3

what is the management of primary myelofibrosis?

Answer 3

Patients with mild disease with minimal symptoms might be monitored and not actively treated.

Allogeneic stem cell transplantation is potentially curative but carries risks.

Chemotherapy can help control the disease, improve symptoms and slow progression but is not curative on its own.

Supportive management of the anaemia, splenomegaly and portal hypertension.

Question 4

what are the management option for polycythaemia vera?

Answer 4

Venesection can be used to keep the haemoglobin in the normal range. This is the first line treatment.

Aspirin can be used to reduce the risk of developing blood clots (thrombus formation).

Chemotherapy can be used to control the disease.

Question 5

what is the management of thrombocytopenia?

Answer 5

Aspirin can be used to reduce the risk of developing blood clots (thrombus formation).

Chemotherapy can be used to control the disease.

Question 6

which disorders is thrombosis part of?

Answer 6

• polycythaemia

- thrombocytopenia

Question 7

what are signs of polycythemia vera?

Answer 7

Conjunctival plethora (excessive redness to the conjunctiva in the eyes)
A “ruddy” complexion
Splenomegaly

Question 8

which genes are associated with myeloproliferative disorders?

Answer 8

JAK2
MPL
CALR

Question 9

what will a blood film for myelofibrosis show?

Answer 9

teardrop-shaped RBCs, varying sizes of red blood cells (poikilocytosis) and immature red and white cells (blasts).

Question 10

which blood test suggests thrombocytosis?

Answer 10

Raised platelet count (more than 600 x 109/l)

Question 11

which blood test suggests suggest polycythaemia vera?

Answer 11

Raised haemoglobin (more than 185g/l in men or 165g/l in women)

Question 12

what is the pathophysiology of myelofribrosis?

Answer 12

Myelofibrosis can be the result of primary myelofibrosis, polycythaemia vera or essential thrombocythaemia.

Myelofibrosis is where the proliferation of the cell line leads to fibrosis of the bone marrow

the proliferating cells produce a cytokine called fibroblast growth factor, which can cause scarring of the bone marrow. the bone marrow can non longer undergo haematopoesis so extra medullary haematopoeisis occurs in the spleen and liver

this can lead to portal hypertension, if it occurs around the spine it can cause spinal cord compression

Question 13

what is myelodysplastic syndrome?

Answer 13

• happens when myeloid cells are not maturing properly
• common in >60y/o who have had previous chemo or radiotherapy
• they have increased risk of transforming to AML

Question 14

what will investigations for myelodysplatic disorder show?

Answer 14

anaemia (fatigue, pallor or shortness of breath)

neutropenia (frequent or severe infections)

thrombocytopenia (purpura or bleeding).

Full blood count will be abnormal. There may be blasts on the blood film.

The diagnosis is confirmed by bone marrow aspiration and biopsy.

Question 15

what are the treatment options for myelodysplastic disorder?

Answer 15

Watchful waiting
Supportive treatment with blood transfusions if severely anaemic
Chemotherapy
Stem cell transplantation