Oncology & Haematology Flashcards
What are the age incidences in cancers?
ALL - 2-6yo
Non-Hodgkin lymphoma - childhood
Hodgkin lymphoma - adolescence
What is acute lymphoblastic leukaemia?
Excessive proliferation of lymphocytes –> many immature lymphocytes
Presents in 2-6yo
Presents insidiously over several weeks
How does ALL present?
Malaise and anorexia Bone marrow infiltration - anaemia (lethargy) - neutropenia (infection) - thrombocytopenia (bruising, petechiae, nose bleeds) - bone pain Reticule-endothelial infiltration - hepatosplenomegaly - lymphadenopathy Other organs - CNS (nerve pansies, headache, vomiting) - testes (enlargement)
How is ALL investigated?
FBC - low haemolytic, thrombocytopenia, circulating leukaemic blast cells
Bone marrow - indicates prognosis
CXR - mediastinal mass
How is ALL treated?
0-4 weeks - induction
- steroids
- IV vincristine
- IT methotrexate
- L-asparaginase
5-8 weeks - consolidation
- steroid
- vincristine
- IT methotrexate
- thiopurine
Maintenance treatment (2yrs girls, 3yrs boys)
- methotrexate (oral and IT)
- prophylactic co-trimoxazole (prevent pneumonia)
- vincristine
Blood transfusions (platelets and whole red cells) - reduce symptoms
What is tumour lysis syndrome?
Systemic and rapid release of intracellular contents as chemotherapy destroys blast cells
- Increased urea
- Increased phosphate
- Increased potassium
- Decreased calcium
Can give allopurinol
What are negative prognostic factors for ALL?
10yo
>50 WBC
Male gender
CNS involvement
What is lymphoma?
Proliferation of cells in lymphatic system (nodes, spleen and liver)
How does non-Hodgkin’s lymphoma present, how is it investigated and treated?
Affects lymph nodes and younger children
Lymphoblastic (mainly T-cell)
- anterior mediastinal mass
- bone marrow, bone, skin, CNS, liver, kidneys, spleen
B cell malignancy (Burkitt)
- lymph nodes in head, neck or abdomen –> pain, intussusception
Ix: bone marrow aspirate, LP, CT, PET scan
Tx: chemotherapy
Px: >80%
How does Hodgkin’s lymphoma present, how is it investigated and treated?
Previous EBV infection, adolescents
Reed-Sternberg cells
Painless lymphadenopathy (neck or mediastinal)
Ix: CT neck, chest, abdo and pelvis, PET scan, bone marrow aspirate, EBV serology
Tx: radiotherapy +/- chemo
Px: >90%
How does NHL and HL differ?
HL
- Reed-Sternburg cells
- upper body
- spreads slowly and receptive to Tx
What are the side effects of chemotherapy?
Hair loss Anaemia Infection Bruising Sore mouth N+V Weight gain Delayed puberty Reduced fertility and growth
What is neuroblastoma?
Arise from neural crest tissue in adrenal medulla and sympathetic nervous tissue
What are the most common cancers in children?
Leukaemia CNS tumours Lymphoma Neuroblastoma Soft tissue sarcoma Wilms tumour Bone tumour Retinoblastoma
Where does haemopoiesis occur?
Fetal - liver
Postnatal - bone marrow
What are the physiological changes in blood count from neonate to adolescence?
Hb - starts high, falls due to increased RBC production and then levels off at adult levels
WBC - starts high and decreases
Platelet - similar to adult
How does iron deficiency arise and how does it present?
Common - sourced from breast milk, formula, cow’s milk or solids
May be due to delay in weaning
Child will tire easily and feed slowly
What does folate deficiency cause?
Body can’t make enough RBC so macrocytic megaloblastic anaemia
What is thrombocytopenia and what does it cause?
Platelet count bruising, petechiae, purpura, mucosal bleeding
What is immune thrombocytopenia?
Destruction of platelets by anti-platelet IgG autoantibodies
Usually post URTI
How does ITP present?
1-2 weeks post URTI
Petechiae, purpura or superficial bruising
Epistaxis, profuse and intracranial bleeding is rare
Mostly acute and self-limiting
How is ITP treated?
Oral prednisolone, IV anti-D or IVIG
What is Von Willebrand disease?
Deficiency in factor responsible for platelet adhesion and carrying factor VIII
How does pattern of bleeding help differentiate cause?
Into mucous membranes and skin - platelet disorder or vWD
Into muscles or joints - haemophilia
Scarring and delayed haemorrhage - disorders of connective tissue
What is haemolytic anaemia?
Reduced RBC lifespan due to increased intra and extravacular destruction
Leads to hepatosplenomegaly, increased unconjugated bilirubin and urinary urobilinogen
What are the causes of haemolysis?
Neonates - autoimmune
Childhood - hereditary spherocytosis, G6PD deficiency, PK deficiency, thalessaemia, sickle cell disease
What is hereditary spherocytosis?
Mutation in gene encoding RBC skeletal protein
RBC loses some of membrane going through spleen –> spheroidal and is destroyed
How does hereditary spherocytosis present and how is it treated?
Around birth
Jaundice, anaemia, splenomegaly, gallstones
Folate supplementation or splenectomy
What is G6PD deficiency?
Commonest RBC problem worldwide esp. central Aftrica
X-linked but female carriers are clinically normal
How does G6PD deficiency present?
Neonatal jaundice
Acute haemolysis precipitated by infection, drugs, ?broad beans
What is pyruvate kinase deficiency?
Lack of enzyme which decreases ATP
Cell becomes rigid and is destroyed in spleen
What is haemophilia A?
Factor VIII deficiency
More common
What is haemophilia B?
Factor IX deficiency
How does haemophilia present?
Most present by 1yo when walking starts
Recurrent spontaneous bleeding into joints and muscles –> arthritis
In neonates - intracranial haemorrahge, oozing from heel prick or post circumcision
What do neuroblastoma arise from?
Neural crest tissue in adrenal medulla ad sympathetic nervous tissue
What is sickle cell disease?
Haemoglobinopathies in which HbS mutations are inherited
Change in amino acid from glutamine to valine
What is sickle cell anaemia?
HbSS (homozygous)
All Hb is HbS (small amount of fetal Hb)
What is sickle-cell haemoglobin C disease?
HbS and HbC from each parent
HbC is different mutation in B-globlin, glutamine to lysine
Not as severe as sickle cell anaemia (HbC doesn’t polymerise as quickly)
What is sickle B-thalassaemia?
HbS and B-thalassaemia
No HbA so similar symptoms to sickle cell anaemia
What is sickle trait?
Inherit HbS and normal B-globin gene
Carriers and asymptomatic
What does HbS do?
Polymerises within RBC to form rigid tubular spiral bodies which deform cells into sickle cells
Reduced life span and may be trapped in micro-circulation –> blood vessel occlusion and ischaemia
Exacerbated by low oxygen tension, dehydration and cold
How does sickle cell disease present?
Anaemia - clinically detectable jaundice
Infection - increased susceptibility to pneumococci and H. influenzae (hyposplenism secondary to microinfarction)
Painful crises - vaso-occlusion in hands and feet, chest
Splenomegaly
Priapism (erectile dysfunction)
What are the long term complications of sickle cell disease?
Short stature and delayed puberty Stroke and cognitive problems Adeno-tonsillar hypertrophy Cardiac enlargement and heart failure - chronic anaemia Renal dysfunction Pigmented gallstones
How is sickle cell disease managed?
Prophylaxis - full immunisation and daily oral penicillin
Daily folic acid
Avoid vaso-occlusive crises - analgesia and hydration if occur
How is sickle cell disease screened for?
Guthrie test
Chorionic villus sampling
What is B-thalassaemia and what are the different types?
Occur in people from Indian subcontinent, Mediterranean and Middle East
Reduction of production of B-globin –> reduction in HbA
B-thalassaemia major - most severe, HbA cannot be produced
B-thalassaemia intermedia - milder, B-globin mutations allow small amount of HbA to be produced
How does B-thalassaemia present?
Severe anaemia and jaundice
Failure to thrive
Extramedullary haemopoiesis –> hepatosplenomegaly and bone marrow expansion (maxillary overgrowth and skull bossing)
What haematological disorder causes a change in facial structure?
B-thalassaemia
Bone marrow expansion in maxillary
How is B-thalassaemia managed?
Lifelong monthly blood transfusions - keep Hb above 100g/l to reduce growth failure and bone deformation
This can cause chronic iron overload –> cardiac failure, liver cirrhosis, diabetes, infertility, growth failure
Treated with iron chelation from 2 years old
Bone marrow transplant will cure
What is the B-thalassaemia trait?
Heterozygotes are asymptomatic
RBC are hypochromic and microcytic
What is alpha-thalassaemia?
Healthy people have 4 alpha-globin genes
No alpha-globin = alpha-thalassaemia major, fetal hydrops
1 alpha-globin = mild to moderate anaemia
2 or 3 alpha-globin = asymptomatic
What is a Wilm’s tumour?
Nephroblastoma - originates from embryonic renal tissue
Most present before 5 years old and it’s very rare after 10
Associated with trisomy 18
How does a Wilm’s tumour present?
Large abdominal mass in otherwise well child
Usually metastasises to lung
How is Wilm’s tumour treated?
Chemo plus delayed nephrectomy
Prognosis is good >80% but recurrence has poor prognosis
What is rhabdomyosarcoma?
Soft tissue sarcoma
Originates from primitive mesenchymal tissue - head and neck, GU
How does rhabdomyosarcoma present?
Head and neck - proptosis, nasal obstruction or bloody nasal discharge
GU (bladder, paratesticular or urethra) - dysuria, urinary obstruction, blood stained vaginal discharge
What is the prognosis for rhabdomyosarcoma?
Metastasis is present in 15% and associated with poor prognosis
When and how do bone tumours present?
Uncommon before puberty
Osteosarcomas are more common
Ewings seen more often in younger children
Persistant bone pain in otherwise well patient
How are bone tumours diagnosed and treated?
X-ray - destruction and new bone formation, Ewing’s has soft tissue mass
Chest CT - lung metastases
Bone marrow sample - exclude marrow involvement
What is disseminated intravascular coagulation?
Disorder of coag pathway –> diffuse fibrin deposition in microvasculature and consumption of coag factors and platelets
Tiny clots and severe bleeding
What are the causes of DIC and how does it present?
SEPSIS or SHOCK
Meningococcal septicaemia
Trauma and burns
Bruising, purpura, haemorrhage
Thrombocytopenia, prolonged prothrombin or APTT, low fibrinogen
How do retinoblastoma present?
Malignant tumour of retinal cells, may affect one or both (hereditary) eyes
Most present within 3 years
White pupillary reflex replaces red one
How are retinoblastomas treated?
Cure but preserve vision if possible
Chemotherapy to shrink tumour and then local laser treatment
What are the indications for splenectomy?
Hereditary spherocytosis, lymphoma, ITP
Trauma
What are the complications of splenectomy?
Low dose Abx needed for life
Malaria
What are side effects of chemotherapy?
Bone marrow suppression - anaemia, thrombocytopenia, bleeding
Immunosuppression - infection
Gut mucosal damage - infection and undernutrition
N+V, anorexia - undernutrition
Alopecia
