Leukaemia
Overview
Leukemia is a common malignancy in children and adults that
occurs when alterations in normal cell regulatory processes cause uncontrolled
proliferation of hematopoietic stem cells in the bone marrow.
Definitions
Leukaemia: Clonal proliferation of hematopoietic stem cells in the bone marrow Acute Leukaemia: Clonal proliferation of hematopoietic stem cells in the bone marrow that develops rapidly, requires immediate treatment and often presents with symptoms. In acute leukaemia the cells in the bone marrow are immature (blasts). Chronic Leukaemia: clonal proliferation of hematopoietic stem cells in the bone marrow that develops slowly, treatment may be delated and often presents asymptomatically. In chronic leukaemia the cells in the bone marrow are still able to mature. Lymphoma: Heterogeneous group of haematological neoplasms, characterised by proliferation of malignantly transformed T or B lymphocytes. The proliferation occur typically in the lymph nodes unlike leukaemia which occir in the bone marrow and result in overcrowding. |
Classification Its important to know that Leukaemia can be divided into
acute and chronic and then further divided into its cell lineage. Remember that
this makes each of them very different diseases.
- Acute leukaemia
- Acute Myeloid leukaemia (adults)
- Acute Lymphoblastic leukaemia (children)
- Chronic Leukaemia
- Chronic Myeloid leukaemia (adults)
- Chronic Lymphoblastic leukaemia (older adults)
- Myelodysplastic syndromes
- Leukemoid reaction
Remember Acute lymphoblastic leukemia occurs more often in
children, whereas the other subtypes are more common in adults
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Clinical
Presentation
- Acute Leukaemia – pancytopaenia
- Acute Lymphoblastic Leukaemia (more common in children)
- Fever
- Lethargy
- Bleeding
- Hepatomegaly
- Splenomegaly
- Lymphadenopathy
- Bone pain
Remember Patients will AML fall ill suddenly and deteriorate
fast, because of Infection, Bleeding (low platelets) and Hyperviscosity
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- Acute Myelogenous Leukaemia
- Constitutional symptoms: Fever, Weight loss, Night sweats
- Anaemia symptoms: Shortness of breath, chest pain
- Thrombocytopaenia symptoms: excessive bruising, nosebleeds, or heavy menstrual periods in women
- Less likely: Bone pain, hepatomegaly and splenomegaly
Causes of
Panytopaenia
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Bone marrow failure – Aplastic
anaemia
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Drugs
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Bone marrow infiltration –
Lymphoma, leukaemia, myeloproliferative disease, myelodysplastic
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Hypersplenism
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SLE
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Sepsis
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Alcohol
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Radiation
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- Chronic Leukaemia – white cell count is high (but nonfunctioning)
- Chronic Lymphoblastic Leukaemia (more common in older adults)
- 50% are asymptomatic
- Hepaosplenomegaly
- Lymphadenopathy
- Chronic Myelogenous Leukaemia
- 20% are asymptomatic
- Splenomegaly
SUMMARY OF
MAJOR LEUKAEMIA
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Subtype
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Description
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Typical Group
affects
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Acute lymphoblastic leukaemia
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Blast cells on peripheral blood
smear or bone marrow aspirate
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Children (53% <20yo)
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Acute Myelogenous leukaemia
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Blast cells on peripheral blood
smear or bone marrow aspirate; Auer rods on peripheral smear
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Adults
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Chronic lymphoblastic leukaemia
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Clonal expansion of at least 5,000
B lymphocytes per μL (5.0 × 109 per L) in the peripheral blood
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Older adults (85% >65yo)
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Chronic Myelogenous leukaemia
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Philadelphia chromosome (BCR-ABL1fusion
gene)
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Adults
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Investigations
for Leukaemia
- Bone marrow aspirate
- Bone marrow biopsy
- Cytogenetic testing
- Flow cytometry with immunophenotyping
- Molecular testing
- Peripheral smear
Treatment
- A patient with suspected leukemia should be referred to a hematologist-oncologist to confirm the diagnosis and initiate treatment.
- Treatment depends on type of leukaemia
Complications
of Leukaemia
- Tumour Lysis Syndrome
- Disseminated Intravascular Coagulopathy – Widespread activation of coagulation, from release of procoagulants into the circulation with consumption of clotting factors and platelets, with ↑risk of bleeding
- Hyperviscosity
- Death
Lê Văn Công
Reference: Armando Hasudungan