Myeloproliferative disorders (zero to finals) Flashcards
What are myeloproliferative disorders?
Myeloproliferative disorders involve the uncontrolled proliferation of a single type of stem cell.
Myeloproliferative disorders usually develop and progress quite quickly. True/false?
False
They are considered a form of cancer occurring in the bone marrow, although they tend to develop and progress slowly.
What can these myeloproliferative disorders transform into as a complication?
AML (acute myeloid leukaemia)
What are the 3 main myeloproliferative disorders?
Polycythaemia vera
Primary myelofibrosis
Essential thrombocythaemia
What is the proliferating cell line in primary myelofibrosis?
Haematopoietic stem cells
What is the blood finding in primary myelofibrosis?
Low haemoglobin
High or low white cell count
High or low platelet count
What is the proliferating cell line in polycythemia vera?
Erythroid cells aka erythrocytes (RBC’s)
What is the blood finding in polycythemia vera?
High haemoglobin
What is the proliferating cell line in essential thrombocythemia?
Megakaryocytes (precursor platelet cells)
What is the blood finding in essential thrombocythemia?
High platelets
What are the 3 main mutations occurring in myeloproliferative disorders?
JAK2 (main one) - treatment is with JAK2 inhibitors i.e. ruxolitinib
MPL
CALR
Which of the myeloproliferative disorders can cause myelofibrosis?
Any of the 3
Myelofibrosis can result from primary myelofibrosis, polycythaemia vera or essential thrombocythaemia.
What is myelofibrosis?
Myelofibrosis is where the proliferation of a single cell line leads to bone marrow fibrosis, where bone marrow is replaced by scar tissue.
How does fibrosis of the bone marrow affect blood cell production?
Fibrosis affects the production of blood cells and can lead to low haemoglobin (anaemia), low white blood cells (leukopenia) and low platelets (thrombocytopenia).
What happens as a result of fibrosis to the bone marrow?
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.
What can a blood film show for myelofibrosis?
Teardrop-shaped red blood cells
Anisocytosis (varying sizes of red blood cells)
Blasts (immature red and white cells)
What are the non-specific symptoms of myeloproliferative disorders?
Fatigue
Weight loss
Night sweats
Fever
What are the potential signs and symptoms of underlying conditions relating to myeloproliferative disorders?
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
What is a common complication of polycythemia (high red cell in blood) and thrombocythemia (high platelets in blood)?
Thrombosis is a common complication of polycythaemia and thrombocythaemia, leading to myocardial infarction, stroke or venous thromboembolism (e.g., DVT and PE).
What are common signs of polycythemia?
Ruddy complexion (red face)
Conjunctival plethora (the opposite of conjunctival pallor)
Splenomegaly
Hypertension
How are myeloproliferative disorders diagnosed?
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.
Management of primary myelofibrosis?
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)
Management of polycythemia vera?
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
Management of essential thrombocythemia?
Aspirin to reduce the risk of thrombus formation
Chemotherapy (typically hydroxycarbamide) to help control the disease
Anagrelide is a specialist platelet-lowering agent
What bone marrow changes occur in myelofibrosis?
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.
Clinical features of myelofibrosis?
Fatigue, weakness, shortness of breath, easy bruising or bleeding, and an enlarged spleen (splenomegaly).
Complications of myelofibrosis?
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.
What could be a cause of myelofibrosis?
Myelofibrosis may develop as a progression of other myeloproliferative neoplasms, such as polycythaemia vera or essential thrombocythaemia.
What is treatment for myelofibrosis?
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.
