[8] Acute Myeloid Leukaemia Flashcards
What is acute myeloid leukaemia (AML)?
A malignant disease of the bone marrow
What happens in AML?
The precursors of blood cells are arrested in an early stage of development
What do most AML subtypes show, in terms of blasts?
More than 30% blasts of a myeloid lineage in blood, bone marrow, or both
What does the mechanism of maturation arrest in an early stage of development in AML involve?
The activation of abnormal genes through chromosomal translocations and other genetic abnormalities
What is the effect of the maturation arrest in an early stage of development in AML?
Reduces the normal blood cells
What does failure of apoptosis in AML lead to?
Accumulation in various organs, especially the liver and spleen
How common is AML, compared to other leukaemias?
It is the most common leukaemia in adults
At what age does AML occur?
It can occur at any age, but the incidence increases with age, and the median age of onset is 67
What are the subtypes of AML?
- AML with characteristic genetic abnormalities
- AML with multi-lineage dysplasia
- AML and MDS, therapy related
- AML not otherwise categorised
Who does the subtype of AML with multi-lineage dysplasia include?
Patients who have had prior myelodysplastic syndrome (MDS) or myeloproliferative disease that transforms into AML
What does the subtype of AML and MDS, therapy related include?
Patients who had had prior chemotherapy and/or radiation
What are the risk factors for AML?
- Other haematological disorders
- Radiation
- Congenital disorders
- Exposure to benzene
- Survivors of cancer chemotherapy
What other haematological disorders increase the risk of AML?
- Myelodysplastic syndrome
- Aplastic anaemia
- Myelofibrosis
What congenital disorders increase the risk of AML?
- Bloom’s syndrome
- Down’s syndrome
- Fanconi’s anaemia
- Neurofibromatosis
What is the presentation of AML related to?
Bone marrow failure or organ infiltration
How does the presentation of AML differ between children and older people?
Children or young adults may present with acute symptoms over a few days to weeks, whereas older people may present with fatigue over weeks or months
What are the symptoms of AML?
- Dizziness and shortness of breath on exertion
- Fever
- Early satiety and fullness in LUQ
- Bone pain
What feature of the fever may be present with AML?
Failure to respond to antibiotics
is that a feature? idk
What causes the early satiety and fullness in LUQ in AML?
Splenomegaly
What are the emergency presentations of AML?
- Haemorrhage into lungs, GI tract, or CNS
- Leukostasis
What cause leukostasis in AML?
Extremely high WBC
What are the most common sites for infiltration of AML?
- Liver
- Spleen
- Gums
Why is knowing the most common sites of infiltration of AML clinically important?
Should look for signs in those locations
What examination features may be present in AML?
- Pallor
- Signs of infection, e.g. fever, pneumonia
- Hepatomegaly and splenomegaly
- Petechiae on lower limbs
- Gingivitis, with swollen, bleeding gums
What does the diagnosis of AML require?
The examination of peripheral blood and bone marrow specimens
What tests are done on the peripheral blood and bone marrow specimens in AML?
- Morphology
- Cytochemistry
- Immunophenotyping
- Cytogenetics
- Molecular genetics
What investigations are done in AML?
- Blood testing
- Bone marrow aspiration
- Allotyping
- Cytochemical testing
What blood tests should be done in AML?
- FBC
- Clotting screen
- LDH
- Liver and renal function
What may be found on FBC in AML?
- Variable degree of anaemia and thrombocytopenia
- Total WBC may be normal, high, or low, and sometimes extremely high
- Neutrophils usually depleted
What condition is commonly found on clotting screen in AML?
DIC
What findings on clotting screen are suggestive of DIC?
- Prolonged thrombin time
- Low level of fibrinogen
- Fibrin degradation products
What happens to LDH in AML?
Usually raised
Why do you need to check liver and renal function in AML?
Must be checked before initiating chemotherapy
What is the importance of bone marrow aspiration in AML?
It is the diagnostic procedure
What findings on bone marrow aspiration are required for a diagnosis of AML?
More than 20% blasts in the peripheral blood
Who should be HLA typed at diagnosis of AML?
Patients potentially suitable for allogenic stem cell transplantation, and their first-degree family members
What is the purpose of cytochemical staining in AML?
It allows for classification of AML into its subtypes
What can cytogenetic studies provide in AML?
Important information about prognosis
What is the usually accepted criteria of therapeutic response in AML?
- Blast clearance in the bone marrow to <5% of all nucleated cells
- Morphologically normal haematopoiesis
- Return of peripheral blood cell counts to normal levels
Where is treatment for AML co-ordinated?
Specialist centres
On what basis is AML treatment delivered?
Two phases
What are the phases of AML treatment?
- Induction
- Post-remission consolidation (intensification)
Is stem cell transplantation an option in AML?
Yes
What are the other aspects of care in AML?
- Blood product replacement
- Antibiotics for infection
- Allopurinol to reduce uric acid levels
What might patients with excessive leukocytosis require before commencing chemotherapy for AML?
Emergency leukophoresis
What is the prognosis of AML dependant on?
- Age
- Cell type
- Burden of disease
- Pre-existing medical conditions
What social factor affects the prognosis of AML?
Prognosis is worse with socio-economic deprivation
What % of people with AML develop secondary malignancies?
13%
What rates of complete remission can be achieved in younger patients?
80%
What is the 5-year survival of AML in younger patients?
40%
What are the remission rates of AML in over 60’s?
60%
What is the limitation of remission in over 60’s?
Remissions are usually transient
What is the median survival of AML in over 60’s?
5-10 months
What pre-existing medical conditions are associated with a poorer prognosis from AML?
- Diabetes
- CHD
- COPD
