MPNs ☺️

Question 1

Pathophysiology

Answer 1

Clonal proliferation of myeloid stem cells in BM

• RBC => polycythemia vera
• WBC => CML
• platelets => essential thrombocythemia
• fibroblasts => myelofibrosis

Question 2

Polycythemia vera

• epidemiology and prognosis
• causes
• presentation

Answer 2

Often in older age, not usually inherited

Malignant proliferation of clone from pluripotent stem cell => excess proliferation of RBC, WBC, platelets
-JAK2 mutation common

Can be asymptomatic, incidental finding on FBC
Hyperviscosity symptoms
-fatigue, confusion
-headache
-visual changes
-itching after hot bath, burning in fingers and toes
Plethoric, splenomegaly, thrombosis

Can remain well
Risk of progressing to MF, AML

Question 3

Polycythemia vera - investigations

Answer 3

FBC

• high RCC, Hb, haematocrit, PCV
• WCC, platelets can be high

Genetic testing - somatic mutation JAK2

US, kidneys, liver spleen - any organ enlargement

BMA - erythroid hyperplasia

Question 4

Polycythemia vera

• management
• complications

Answer 4

Keep haematocrit low to keep thrombosis risk low

• venesection/hydroxycarbamide
• give aspirin

Monitor FBC 3monthly
-thrombosis, haemorrhage risk

Question 5

Essential thrombocythemia

• epidemiology
• causes
• presentation

Answer 5

Often in older age, not usually inherited

Clonal proliferation of megakaryotes => high platelets with abnormal function
-JAK2 common

Clot formation, symptoms depend on location

• headache, dizzy, lightheaded
• chest pain
• visual changes
• numb hands and feet
• DVT, PE, thrombosis

Easy bleeding
-nosebleed, bruising, mouth/gums, bloody stools

Question 6

Essential thrombocythemia - investigations

Answer 6

FBC - high platelets
Coagulation, platelet aggregation studies

Genetic testing - somatic mutation JAK2

US spleen

BMA - megakaryocytic proliferation

Question 7

Essential thrombocythemia - management

Answer 7

Daily aspirin

-add hydroxycarbamide (chemo) if needed

Question 8

Essential thrombocythemia -

• management
• prognosis

Answer 8

Daily aspirin
-add hydroxycarbamide (chemo) if needed

Does not reduce life expectancy

• chance of MF, AML progression
• risk of thrombosis, clots

Question 9

Myelofibrosis

• epidemiology
• causes
• presentation

Answer 9

Middle, older adults
-JAK2 common

Often asymptomatic
B symptoms

Splenomegaly
BM failure - pancytopenia

Question 10

Myelofibrosis

-investigations

Answer 10

FBC - anemia, WCC/platelets variable

Genetic testing - somatic mutation JAK2

US spleen

BMA - BM fibrosis

Question 11

Myelofibrosis

• management
• prognosis

Answer 11

If symptomatic
BM support
-tranfusions

Splenomegaly
-chemo, radiation, targeted drugs

Allogenic BM stem cell transplants

Median survival - 4-5 years