Haematology II: Leukaemias and Lymphomas Flashcards
What are leukaemias?
Malignant neoplasms of haemopoietic stem cells which result in diffuse replacement of bone marrow and normal blood precursor cells by neoplastic cells.
What does this bone marrow failure lead to?
Anaemia
neutropenia - low number of white blood cells called neutrophils in your blood.
thrombocytopenia - deficiency of platelets in the blood. This causes bleeding into the tissues, bruising, and slow blood clotting after injury.
Leukaemic cells can then spill over into blood & may infiltrate organs
How are leukaemias classified?
They’re classified on basis of cell type involved and its maturity i.e. for cell type:
-Myeloid cell line
-Lymphoid cell line
And for maturity:
-Acute leukaemia (>50% of cells present are myeloblasts or lymphoblasts in bone marrow at clinical presentation)
-Chronic leukaemia (cells are more differentiated)
What is the diagnosis of leukaemias based on?
Blood film
Diagnosis suggested due to abnormal WCC, as well as presence of immature blast cells which are not normally present in the peripheral blood,
How is a leukaemia diagnosis confirmed?
Bone marrow aspirate (if it’s hypercellular and there are numerous blast cells, this is considered an indicator)
What important prognostic indicators can be ascertained from doing a blood film and bone marrow biopsy?
Leukaemia type
Cell phenotype
Chromosomal abnormalities
What are the possible causes of leukaemia?
Ionising radiation
Chemicals including benzene and alkylating agents
Viruses (e.g.. HTLV - human T-cell leukaemic virus)
Genetic factors (e.g.. Down’s syndrome)
Acquired haematological disorders such as aplastic anaemia
What does the neoplastic cell infiltration in the bone marrow result in?
Anaemia
pallor
malaise - a general feeling of discomfort, illness, or unease whose exact cause is difficult to identify.
fever & infections
bleeding
bruising/petechiae
What can tissue infiltration of the neoplastic cells look like?
slide 13
Who does acute lymphoblastic leukaemias (ALL) typically affect?
Children: peak incidence of 4-5 years old
How is ALL managed?
Remission induced with non-myelosuppressive chemotherapy
2-12 years >60% cure rate with chemotherapy
Adults 20% cure rate
Combination chemotherapy to induce remission
CNS treatment performed prophylactically
Maintenance therapy for up to 2 years increases disease-free survival
Who is typically affected by acute myeloid leukaemia (AML)?
It’s the most common leukaemia in adults but the incidence increases with age
There are also genetic factors at play: children with Down’s syndrome are 400x more likely to develop AML than the general population
How is AML managed?
> 80% cure rate with intensive chemotherapy in young patients
15% resistant disease
4-5 courses of intensive
chemotherapy (each lasting 5-10 days)
No maintenance therapy
Autologous and allogenic stem cell transplant
How common is chronic lymphocytic leukaemia (CLL) and who is typically affected?
Accounts for 25% of all leukaemias and typically more prevalent in elderly population (>60yrs) and tends to be more common in men than women, with a 2:1 ratio.
What are the clinical features of CLL?
-Constitutional symptoms
-Lymphadenopathy
-Splenomegaly
-Recurrent infections
-Abnormal FBC (anaemia, thrombocytopenia)
-Hypogammaglobinaemia
How is CLL treated?
Asymptomatic patients do not require treatment (monitoring only)
30% of patients with early stage disease die of unrelated cause
Chemotherapy typically effective
Median survival 10-12 years
Mortality usually due to infection or bone marrow failure
Bone marrow transplantation occasionally attempted in younger patients with poor prognostic disease
How prevalent is chronic myeloid leukaemia (CML) and who is typically affected by it?
Accounts for <20% of all leukaemias
Median age of onset is 40-50yrs & there is a slight male predominance.
How is CML treated?
The initial chronic phase may last for years and needs no treatment and simple monitoring
It may develop into an accelerated phase before developing a blast crisis at which point treatment is initiated