HAEM - Acute & chronic leukaemia Flashcards
From what do leukaemias arise from?
Stem cell & progenitor cell populations (e.g. multipotential progenitor, common lymphoiad progenitor, common myeloid progenitor, megakaryocyte erythrocyte progenitor)
List (4) examples of lymphoid mature cells
NK cells
T cells
B cells
Dendritic cells
List (8) examples of myeloid mature cells
Neutrophils Eosinophils Mast cells/Basophils Megakaryocyte/Platelets!! Monocyte/macrophage/Kupffer cells Dendritic cells Erythrocyte
Define leukaemia
Cancer that starts in blood forming tissue such as the bone marrow and causes large numbers of blood cells to be produced and enter the blood stream
Circulating malignant cells of hematopoietic origin in the blood or bone marrow
Etiology of Leukemias
Unknown in majority
Etiological factors include:
–Previous cytotoxic therapy
–Exposure to ionizing radiation
–Chemical exposure e.g. benzene
–Infections e.g. adult T cell leukemia lymphoma and HTLV-1
–Genetics e.g. trisomy 21 (Down Syndrome) and high risk AML
–Rare familial syndromes e.g. fanconi’s anaemia 52% develop AML or MDS by age 50
(4) Clinical Presentation of Acute Leukemia
–Anemia: Lethargy, dyspnoea, pallor, presyncope
–Neutropenia: Fevers / rigors, infections
–Thrombocytopenia: Bruising, bleeding
–B symptoms: Fevers, sweats, weight loss
–Less commonly: lymphadenopathy, hepatosplenomegaly, symtpoms of hyperleucocytosis
Which leukaemia can occasionally have a mediastinal mass?
Acute lymphocytic leukaemia -> SVC obstruction -> red face, dyspnoea, cough
(5) Key Investigations in Acute Leukemia
- Full blood count and film
- Bone marrow biopsy
- Immunophenotyping
- Cytogenetics
- Molecular studies
Aim of these tests is to determine the type of leukaemia, the prognosis and how best to monitor response to therapy
What (2) do you expect to see on blood film of AML?
Cytopaenia due to suppression of normal haematopoiesis
Blasts (large nucleus, little cytoplasm. Nucleus looks immature; big nucleoli)
Monomorphic. (looks pretty identical)
What % of infiltration by malignant cells is classified as acute leukaemia?
> 20% blasts of nucleated cells
What is Auer rod pathognomic for?
AML
What markers of immunophenotyping do you look for in AML?
- myelodi markers
- immature markers
e.g. CD34, CD33, CD11
What markers of immunophenotyping do you look for in ALL?
- immature T&B cell markers -> determine subtype of ALL
Discuss cytogenetics in AML
It determines the prognosis
- Good risk: t(8;21), inv 16, t(15;17) -> can be cured with standard chemotherapy
- Intermediate risk: (70% pts): mostly normal cytogenetics
- Poor risk: monosomy 7, multiple complex abnormalities, chromosome 3 abnormalities -> must have transplant to have a chance of cure
Discuss molecular testing in AML & its relationship to prognosis
especially important for intermediate risk group by cytogenetics (majority) to help better predict prognosis
molecular testings are more sensitive than cytogenetics (cytogenetics needs a lot of cells)
- FLT3 internal tandem duplication: poor prognosis
- nucleophosmin (NPM1) & CEBPA: good prognosis
How (4) do you monitor response to therapy in acute leukaemia after chemotherapy?
- Marrow aspirate and trephine:
- less than 5% = morphological remission - Cytogenetics:
- CG remission = disappearance of any previous abnormalities - Flow cytometry
- Remission = no detection of cells with aberrant phenotype - Molecular studies
- Remission = no detectable transcript if a quantifiable translocation eg AML1-ETO in t(8;21 ); serial zero levels c/w remission and likely cure but rising levels may impend relapse
What are the principles of treatment in AML?
- determine appropriate treatment according to age, condition, prognosis
- palliative for elderly & poor prognosis
- induction chemotherapy for fit pts (cytarabine & anthracycline)
- determine response after marrow recovery
- if good response, consolidation cycles (x2 in AML) with marrows after each cycle to check disease status
- determine need of allogeneic transplant based on age (usually eligible if younger than 60yo) & prognostic features