Acute Leukaemia Flashcards
Acute Leukaemias
All this happens in the bone marow:
Normal blasts 1-2%
Acute leukaemia > 20% - crowds out normal cells
- loss of RBCs - Anaemia/fatigue
- loss of platelets - thrombocytopaenia
- loss of neutrophils - infection
Blasts spill out into bloodstream causing white cell count to increase
Acute Leukaemias
Lymphoid or Myloid?
Whether the leukaemia is lymphoid or myeloid makes a difference to treatment
So look for markers:
Lymphoblasts - positive cell staining for TdT in cell nucleus (TdT is a DNA polymerase only in lymphoblasts)
Myeloblasts - presence of myeloperoxidase
Acute Leukaemias
Lymphoid or Myloid?
Lymphoblasts present!
B-Lymphoblasts
Can get B acute lymphoblastic leukaemia B-ALL
Can get T acute lymphoblastic lleukaemia T-ALL
- Most common surface markers C10, C19, C20
- Treatment via chemo is good but will need injections into scrotum and CSF as doesn’t cross blood brain barrier
Prognosis can depend on cyto genic abnormalities:
- t(12:21) good, normally children
- t(9:22) poor adults
Acute Leukaemias
Lymphoid or Myloid?
Lymphoblasts present!
T-Lymphoblasts
- T-Lymphoblasts express CD2-CD8 surface markers
- Can get a Thymic mass most common in teenagers - known as ACUTE LYMPHOBLASTIC LYMPHOMA (not leukaemia coz these float around in blood)
Acute Leukaemias
Lymphoid or Myloid?
Myeloblasts present!
- Looking for myeloperoxidase (enzyme)
- Common in adults between 50-60
Subdivided:
- cytogenic abnormalities
- Lineage
- surface markers
there is a dysfunction in retinoic acid receptors causing build up PROMYELOCYTES
Giving lots of Auer rods - coagulation risk - diseminated intravascular coagulation
Can be treated with Altrans retinoic acid ATRA
Acute Leukaemias
Lymphoid or Myloid?
Myeloblasts present!
Classification by lineage:
Acute monocytic leukaemia:
- build up of monoblasts
- often no myeloprotein
- infiltrates gum
Acute megakaryoblastic leukaemia:
- often no myeloperoxidase
- associated with Downs Syndrome
Acute Leukaemias
Lymphoid or Myloid?
Acute myeloid leukaemia - Myelodysplastic syndrome
Have blast build up in bone but< 20% so not considered AML
Get low blood count - cytopaenia leading to infection and then death
Can progress to acute myeloid leukaemia if blasts > 20%
they then have AML with a background of myelodysplasia
