L11. Blood cancers Flashcards
What are the 4 types of blood cancers and give example/ classification
- Leukaemia : acute and chronic
- Myeloproliferative neoplasms- eg. polycythaemia vera (Hb), essential thrombocythemia (platelets)
- Lymphoma: hodgkin (yo adults + 60yrs+) vs non-hodgkin. Tumours of the lymphoid system
- Myeloma
What are the features of myeloproliferative neoplasm and the pathology
- High Hb, WBC, RBC, platelets
- enlargement of liver and spleen
- Chronic disorder
Normal differentiation of blood cells but clonal proliferation due to DNA abnormality. eg. jak2 mutation for constitutive activation of TPO receptor
What are the features and pathology of Myeloma
- Malignant proliferation of plasma cells in the bone marrow, infiltrating the bone marrow
- Patients often have lytic bone lesions anywhere in the body
- Associated with monoclonal paraprotein (IgG, IgA) all the same antibody produced because its clonal
What are the features of presentation and general cause of Leukaemia
Clonal proliferation of immature bone marrow cells (progenitor cells/blast cells), expand in the bone marrow, replace normal cells (impaired production) and spill into the blood.
What are the two types of chronic leukaemia - which is most common over 70yr+. What is CML caused by and what is the presentation of CLL
Chronic myeloid leukaemia –> kind of like myeloproliferative , due to having philadelphia chromosome: translocation of 9;22, leads to BCR-ABL fusion gene-> tyrosine kinase which drives leukaemic cell proliferation.
Chronic lymphocytic leukaemia –> most common 70yrs+
Can show with enlarged lymph nodes, splenomegaly,, lymphocytosis with presence of smear cells
What are the 2 types of acute leukaemia and which is common in adults; children: compare the remission/long term remission rate
Occurs at all ages. 2-3 cases per 100 000
Acute myeloid leukaemia: 85% of adults - worse remission and long term remission than below
Acute lymphoblastic leukaemia: 85% of children
What are the risk factors for acute leukaemia (4)
- Though Most causes cannot identify environmental or congenital risk factor
- Congenital/inherited risk factors eg. Trisomy 21= 200x risk
- Viral infections (eg. DHTLV in T cell leukaemia (rare))
- Radiation exposure
-Chemical/DNA damaging drugs -eg. chemotherapy.
This + radiotherapy can lead to therapy related leukaemia
How is molecular testing used in leukaemia (3) and give an example of its use in treatment of acute leukaemia/ chronic myeloid leukaemia
- Used to identify the driver mutations for the acute leukaemia (pathogenesis)
- Genetic changes are stratified into risk groups leading to prognostic predictions - even though its the same leukaemia, eg. AML
- Allows identification of targets for treatment (expensive)
eg. In CML Philadelphia chromosome - translocation of 9;22, leads to BCR-ABL fusion gene-> tyrosine kinase which drives leukaemic cell proliferation.
Its ATP binding site can be blocked with imatinibs
What are the signs of acute leukaemia (5) - due to bone marrow failure - one in ALL
- Pancytopenia
- hypercellular marrow - increased leukaemia cells
- Anaemia: fatigue, dyspnoea on exertion or rest, chest pain, pallor
- Neutropenia: (low neutrophils) recurrent skin/resp infections, slow healing wounds
- Thrombocytopenia: bruising, bleeding, petechiae
- Enlarged 2ndary lymphoid organs- in ALL: liver, spleen, lymph nodes, gums
How is the diagnosis of leukaemia ALL vs AML made on blood count and bone marrow biopsy- diagnostic test
- Blood count
- Low Hb/anaemia- low haematocrit
- White cell normal/increased due to circulating blasts - high buffy coat, but neutrophils low
- Severe thrombocytopenia (<20) - Bone marrow aspirate, trephine
>20% blasts: myeloid or lymphoid lineage
Immunophenotype determines ALL vs AML using fluorescent labelled antibodies for proteins
(+ Chromosome and molecular testing done also)
What is the Supportive care/therapy for Acute leukaemia
Done at AKL hospital which covers northland
- Intensive transfusion support, with RBCs and platelets.
- Management of infection- ID and lab support, antibiotic therapy
- Vascular access using tunneled venous catheters - into the jugular vein. allowing easy administration for drugs, stem cells, taking blood samples
- Patient and family support
What is the timeline of chemotherapy for acute leukaemia : intent to cure
- Induction to induce remission
- this may include haematopoietic stem cell transplant - consolidation to mop up residual leukaemia cells undetected
- 2ys of tablet based maintenance therapy *only in ALL to keep patient in remission
