Leukaemia Flashcards
Define Leukaemia
Progressive, malignant disease of the blood-forming organs, characterised by distorted proliferation and development of leukocytes and their precursors in the blood and bone marrow
What is the difference generally between acute and chronic leukaemias
Acute leukaemia = the haemopoietic cells lose their ability to differentiate/mature into the end cells, remaining as precursor cells (blasts >20%)
Chronic leukaemia = the haemopoietic cells proliferate and differentiate but are non-functioning
What is the cell development lineage
Blood stem cell -> myeloid or lymphoid cell
Myeloid: RBCs, platelets, granulocytes (neutrophils, eosinophils, basophils)
Lymphoid: B lymphocytes, T lymphocytes, Natural killer cells, plasma cells
Describe Acute myeloid leukaemia
Most common acute leukaemia in adults
Myeloblasts, arrested at an early stage of development, undergo malignant transformation and proliferation -> replacement of normal bone marrow -> bone marrow failrue
Describe acute lymphoblastic leukaemia
Most common malignancy of childhood
Lymphoblasts (arrested at an early stage of development) undergo malignant transformation and proliferation →subsequent replacement of normal marrow → bone marrow failure and infiltration into other tissues
B lymphoblasts - B-ALL
T lymphoblasts - T-ALL
RF: radiation, viruses, Down’s, Fanconi’s anaemia, siblings with ALL
Symptoms and signs of Acute myeloid leukaemia
Anaemia → pallor, lethargy, SOB
Thrombocytopenia → bleeding, ecchymoses
Neutropenia → opportunistic, recurrent infection
Tissue infiltration:
Gum swelling/hypertrophy
CNS involvement (headaches, nausea, diplopia)
Skin rashes
Rare: deposits of leukaemic blasts in the eye, tongue and bone (fractures)
Symptoms of signs of acute lymphoblastic leukaemia
Bone marrow failure
Anaemia → pallor, lethargy, SOB
Thrombocytopenia → bleeding gums, bruising, menorrhagia
Neutropenia → opportunistic, recurrent infection
Meningeal involvement (headache, visual disturbance, nausea)
Tissue/organ infiltration Testicular swelling Thymic swelling → Mediastinal compression Hepatosplenomegaly Lymphadenopathy Tender bones Cranial nerve palsies Retinal haemorrhage or papilloedema, leukaemic infiltration of the anterior chamber of the eye
Describe Chronic myeloid leukaemia
Chromosomal translation t(9,22) - Philadelphia Chromosome (fusion of genes BCR and ABL) -> malignant proliferation of stem cells
Male more common (4:1)
3 phases
- Relative stable chronic phase of variable duration (4-6 years)
- Accelerated phase (3-9 months)
- Acute leukaemia phase - blast formation
Symptoms and signs of chronic myeloid leukaemia
50% asymptomatic - diagnosed on routine blood count
Systemic: weight loss, sweating
Bone marrow failure
- Anaemia → pallor, lethargy, SOB
- Thrombocytopenia → bleeding gums, bruising, menorrhagia
Abdominal discomfort, early satiety
Gout or hyperviscosity symptoms (headaches, visual disturbance, pruritus, worse after bath)
Blast crisis with symptoms of AML or ALL
Splenomegaly (90%)
Bone marrow failure → cardiac flow murmur
Describe chronic lymphocytic leukaemia
90% are >50, M>F
Cells are unable to apoptose
RF: haemolytic anaemia, thrombocytopenia, Evan’s syndrome
Symptoms and signs of Chronic lymphocytic leukaemia
Asymptomatic (50%): diagnosed on routine blood count
Systemic: fatigue, night sweats
Bone marrow failure:
Recurrent infections, herpes zoster
Easy bruising/bleeding
Late stages: pallor, purpura/ecchymoses, cardiac flow murmur (bone marrow failure)
Lymphadenopathy
Hepatomegaly
Splenomegaly
What are the characteristic findings on investigations for acute myeloid leukaemia
Blood films: Auer rods (large nucleocytoplasmic ratio and cytoplasmic inclusions) | AML blasts may show cytoplasmic granules
Immunohistochemistry: Myeloblast granules +ve for Sudan black staining
FBC: Anaemia | thrombocytopenia
Clotting: ?DIC
Bone marrow aspirate or biopsy: hypercellular >30% blasts
What are the characteristic findings on investigations for acute lymphoblastic leukaemia
Blood film + TdT nuclear staining: Lymphoblasts | Postive TdT staining (positive in lymphoblasts, negative in lymphocytes and myeloblasts)
FBC: Anaemia | thrombocytopenia
CXR: mediastinal lymphadenopathy | thymic enlargement | lytic bone lesions
Bone marrow aspirate or biopsy: hypercellular >30% blasts
What are the characteristic findings on investigations for chronic myeloid leukaemia
Blood film: Left shift | immature granulocytes
Cytogenetics: Philadelphia chromosome (t9:22)
FBC: raised WCC, basophils, neutrophils etc. | anaemia
Bone marrow aspirate or biopsy: hypercellular with raised myeloid: erythroid ratio
What are the characteristic findings on investigations for chronic lymphocytic anaemia
Blood film: smudge/smear cells | small lymphocytes
FBC: raised lymphocytes | anaemia | thrombocytopenia
Bone marrow aspirate/biopsy + immunophenotyping: lymphocytic replacement
