Myeloproliferative Neoplasms Flashcards
Define myeloproliferative disorders
Uncontrolled proliferation of a single type of stem cell
Myeloproliferative disorders have the potential to transform into..
Acute myeloid leukaemia
Proliferating cell line of Primary Myelofibrosis
Haematopoietic stem cells
Proliferating cell line of Polycythaemia Vera
Erythroid cells
Proliferating cell line of Essential Thrombocythaemia
Megakaryocyte
Low haemoglobin
High or low white cell count
High or low platelet count
Primary Myelofibrosis
High haemoglobin
Polycythaemia Vera
High platelet count
Essential Thrombocythaemia
Give examples of BCR-ABL1 positive myeloproliferative neoplasms
CML
Give examples of BCR-ABL1 negative myeloproliferative neoplasms
Primary myelofibrosis
Polycythaemia vera
Essential thrombocythaemia
When to consider a MPN?
High granulocyte count
High RBCs
High Platelet count
Eosinophilia/basophilia
Splenomegaly
Thrombosis in an unusual place
With NO reactive explanation
MPNs are associated with mutations in certain genes..
JAK2
MPL
CALR
What causes Myelofibrosis?
In response to fibroblast growth factor released from the proliferating cells leading to pancytopenia
When the bone marrow is replaced with scar tissue, haematopoiesis starts to happen in other areas, known as…
Extramedullary haematopoiesis:
Liver, spleen, and around the spine
A blood film in myelofibrosis can show..
Teardrop-shaped red blood cells
Anisocytosis (varying sizes of red blood cells)
Blasts (immature red and white cells)
________ is a complication of polycythaemia
Gout
_________ is a common complication of polycythaemia and thrombocythaemia, leading to myocardial infarction, stroke or venous thromboembolism
Thrombosis
What does the clinical picture show?
Polycythaemia
Ix for MPN
Bone marrow biopsy
Testing for the JAK2, MPL and CALR genes
Mx for primary myelofibrosis
Chemotherapy (e.g., hydroxycarbamide)
Targeted therapies, such as JAK2 inhibitors (ruxolitinib)
Allogeneic stem cell transplantation
Mx for polycythaemia vera
Venesection
Aspirin
Chemotherapy (typically hydroxycarbamide)
Mx for essential thrombocythaemia
Aspirin
Chemotherapy (typically hydroxycarbamide)
Anagrelide
In Myelofibrosis, the resultant release of platelet derived growth factor is thought to stimulate _________
Fibroblasts
In Myelofibrosis, haematopoiesis develops in the ____ and _____
Liver and spleen
Elderly person with symptoms of anaemia e.g. fatigue
Massive splenomegaly
Hypermetabolic symptoms: weight loss, night sweats etc
Myelofibrosis
What does the blood film show?
Typical ‘tear-drop’ poikilocytes of myelofibrosis
Anaemia
High WBC and platelet
High urate and LDH
Myelofibrosis
Myelofibrosis often causes an unobtainable bone marrow. What would be an alternative?
Trephine biopsy
Pruritus, typically after a hot bath
Splenomegaly
Hypertension
Hyperviscosity - arterial/
venous thrombosis
Haemorrhage
Low ESR
Polycythaemia vera
Ix for PV
FBC
JAK2 mutation
Serum ferritin
Renal and liver function tests
If the JAK2 mutation is negative and there is no obvious secondary cause, then test for
Red cell mass
Arterial oxygen sats
Abdominal US
Serum erythropoietin level
Bone marrow aspirate and trephine
Cytogenetic analysis
BFU-E culture
Other features that may be seen in PRV include a high/low ESR and a raised/reduced leukocyte alkaline phosphatase
Other features that may be seen in PRV include a low ESR and a raised leukocyte alkaline phosphatase
Diagnostic criteria for JAK2-positive polycythaemia vera
Diagnostic criteria for JAK2-negative polycythaemia vera
Diagnosis requires A1 + A2 + A3 + either another A or two B criteria
Causes of severe thrombocytopenia
ITP
DIC
TTP
haematological malignancy
Pseudothrombocytopenia has been reported in association with the use of..
EDTA as an anticoagulan
