Leukaemia Flashcards
What is leukemia?
= malignancies of blood cells and their precursors
Characteristically associated with increase of number of white cells in bone marrow or/and peripheral blood
What is the visual difference between normal blood and leukemia?
What are haematopoietic stem cells?
Multipotent - can give rise to cells of every blood lineage
Self maintaining - a stem cell can divide to produce more stem cells
Can give rise to progenitor cells - myleoid and lymphoid
What does leukemia being a clonal disease mean?
all the malignant cells derive from a single mutant stem cell (gives rise to pre-leukaemia state)…
…Then a second mutation is required for the full blown leukaemia infection
What is the presentation of leukaemia?
Abnormal bruising
Repeating abnormal infection
- Due to low white blood cell
Sometimes anaemia
- Low haemoglobin - shortness of breath and dizziness and fever
How can you diagnose leukemia?
Peripheral blood blasts test - to check for presence of blasts and cytopenia
- >30% blasts in blood = acute leukaemia
Bone marrow test/biopsy - taken from pelvic bone and results compared with above
Lumbar puncture - to see if it has spread to cerebral spinal fluid (CSF)
What are the different ways you can characterise leukaemia?
What is the cause of leukemia?
Cause is unclear - although NOT hereditary, usually somatic
Combination of predisposing factors
Genetic and environmental as well as lifestyle and unproven factors
What are the risk factors for leukemia?
Genetic risk factors:
- Gene mutations involving oncogenes and tumour supressing
- Chromosome aberrations - translocations or numerical disorders
- Inherited immune system problems
Environmental risk factors:
- Radiation exposure
- Exposure to chemicals and chemotherapy
- Immune system suppression - after organ transplant
Lifestyle factors:
- Weight
- Drinking
- Smoking
Other factors:
- Mother’s age when child is born
- Infections early in life
- Nuclear power stations
- Parent’s smoking history
What are the 4 types of leukemia?
What is the basics differences between acute and chronic disease of leukemia?
Acute disease:
- Rapid onset and short but severe
- Weeks to months
- mainly children
- Undifferentiated
- Characterised by uncontrolled clonal and accumulation of immature white blood cells (myeloblast and lymphoblast)
Chronic disease:
- Persisting over long time
- Differentiated leukaemia
- Characterised by uncontrolled clonal and accumulation of mature white blood cells (-cytes)
- Middle age and elderly
What is acute leukaemia?
Large number of lymphoblasts (ALL) or myeloid blasts (AML) in bone marrow and blood-undifferentiated leukaemia
Typical symptoms:
- Thrombocytopenia - bruising, nosebleed and bleeding from gums
- Neutropenia - recurrent infections
- Anaemia - weakness, shortness of breath
What is the difference between ALL and AML acute leukaemia?
ALL
- Most common cancer in childhood
- Cancer of immature lymphocytes
- B-cell and T-cell leukaemia
- Treatment - chemotherapy
- Outcome - 5 year event-free survival, 1 in 10 relapse
AML
- Very rare
- Cancer of immature myeloid white blood cells
- Treatment - chemotherapy, monoclonal antibodies immunotherapy, bone marrow transplant
- Outcome - 5-year event-free survival
What is the 2 types of chronic leukaemia?
Increased number of differentiated cells
CLL
- 3,800 new cases each year, older people
- Large numbers of mature lymphocytes in bone marrow and peripheral blood
- Symptoms - recurrent infections, anaemia, thrombocytopenia, lymph node enlargement
- Treatment - regular chemotherapy
- Outcome - 5-year event-free survival
CML
- 742 new cases each year, low onset and low prevalence
- Large numbers of mature myeloid white blood cells
- Often asymptomatic and seen in routine blood tests
- Diagnosis - high white cell count and presence of Philadelphia chromosome
- Treatment - target therapy of Imatinib
What is BCR-ABL oncogene-Imatiinib therapy?
95% of cases of CML has Philadelphia chromosome from balance translocation
Unregulated BCR-ABL activity causes:
- Proliferation of progenitor cells in absence of growth factors
- Decreased apoptosis
- Decreased adhesion to bone marrow stroma
