Leukaemia Flashcards
What is acute leukaemia?
aggressive disease in which malignant transformation occurs in a haemopoietic stem cell or early progenitor
- accumulation in bone marrow of early haemopoietic cells known as blast cells -> BM fail
When would you diagnose an acute leukaemia?
presence of atleast 20% of blast cells in BM or blood at clinical presentation
- lineage of blast cells defined with flow cytometry, morphology
- cytogenetic and molecular analysis essential and performed on marrow cells
What causes disease burden in acute myeloid leukaemia?
uncontrolled proliferation of immature, non-functional white blood cells ‘blasts’
- causes pancytopenia and haematopoiesis and presents that way
- blast cells enter blood stream and infiltrate other organs
What cells are involved in the myeloid lineage?
monocytes, granulocytes (eosinophil, basophil, neutrophil), erythrocytes, and platelets
What are the risk factors of AML?
- myelodysplastic syndrome and other pre-existing haematological disorders
- MDS, MPD, aplstic anaemia, paroxysmal nocturnal haemogloburia
- de-novo malignancy
- congenital disorders: Down’s syndrome, bloom syndrome
- environmental exposure: prior chemotherapy, radiation, tobacco smoke, benzene
- no identifiable cause: genetic alterations, isolated gene mutations
What are the clinical features of AML?
anaemia signs
thrombocytopenia - mucosal bleeding, easy bruising, petechiae, bleeding gums
neutropenia - infection
leukaemia infiltration
What clinical signs can be seen in AML?
- weight loss
- anaemia: pallor and cardiac flow murmur
- fever, pneumonia signs
- petechia, dermal bleeding and ecchymoses
- hepatosplenomegaly, lymphadenopathy and swollen gums
How would you investigate AML?
FBC - pancytopenia
peripheral blood smear - myeloblasts, auger rods
LDH - increased cell turnover
coagulation profile
BM biopsy
What diagnoses AML?
> 20% myeloid blasts in BM (or peripheral blood) or detecting cytogenetic abnormalities
How is AML managed?
- chemo: induction, consolidation, maintenance
- BM transplant
- Supportive therapy: blood transfusions, analgesia, abx, allopurinol, anti-emetics
What complications can be caused by AML ?
DIC
leukostasis
tumour lysis
What is acute lymphoblastic leukaemia?
most common childhood cancer with peak age 2-6 years
- arises from a clone of lymphoid progenitor cells
- buildup of these cells causes pancytopenia
*chromosomal translocations seen - t(12;21) most common and Philadelphia t(9;22)
What are some risk factors of ALL?
- Trisomy 21, Bloom syndrome, ataxia-telangiectasia
- pre-natal exposure to XR
- in-utero exposure to infection
- delayed post-natal exposure to infection
- environmental radiation
How might ALL present?
marrow failure
tissue infiltration - hepatosplenomegaly, bone pain, mediastinal mass, testicular enlargement
leucostasis
general B sx
How might you investigate ALL?
FBC - pancytopenia
hyperaemia, high LDH, hypercalcaemia
coagulation screen
bone marrow - 50 to 98% blasts
CSF
CXR
CT CAP
cytogenetics