Haematology/Oncology Flashcards
What is the most common cause of microcytic and hypochromic anaemia?
Iron deficiency
How do red cells appear if they are microcytic and hypochromic?
Small and pale (not enough stuff for the pillowcases)
How is anaemia defined in children aged 12-14 years?
Hb below 120g/L
What does the serum ferritin level need to be less than, to confirm iron deficiency?
15 micrograms/L
What are the causes of iron deficiency anaemia?
- Dietary deficiency (poverty, fad diets, exclusive breast feeding >6 months)
- Malabsorption
- Increased loss
What are the possible causes for malabsorption in children? (3)
- Coeliac disease
- IBD
- High cows milk intake - blocks iron absorption (protein enteropathy)
What are the causes of increased blood loss in children that can lead to iron deficiency anaemia? (5)
- Meckel’s diverticulum
- Angiodysplasia
- Oesophagitis
- Adolescent girls starting puberty
- NSAIDs
What are the symptoms of iron deficiency anaemia? (5)
- Pale skin
- Lack of energy
- Breathlessness
- Reduced cognitive and psychomotor performance
- Pica (rare)
Why is iron deficiency anaemia a sign, not a diagnosis?
Because there is an underlying cause that will require treatment or modifying e.g. diet
What is the treatment for iron deficiency anaemia?
1.5-2mg/kg iron per day (oral ferrous salt)
How long do the ferrous salts need to be taken for and why?
3 months after Hb normalises to replenish body stores
What are the iron-containing foods that should be encouraged as part of a healthy diet, particularly if someone has iron-deficiency anaemia? (9)
- Iron fortified formulas and breakfast cereals
- Meat
- Green vegetables
- Beans
- Egg yolk
- Foods rich in vitamin C (increase absorption of iron)
- Fish
- Apricots, prunes, raisins
- Oatmeal
What is important to tell parents when they are giving their children iron supplements?
It is normal for their stools to be black
What is the main cause of macrocytic anaemia?
B12 or folate deficiency
What is the other name for vitamin B12?
Cobalamin
What are the causes of B12 and folate deficiency? (5)
- Not enough B12 in the diet
- Intrinsic factor deficiency
- Folate deficiency
- Malabsorption e.g. coeliac disease, IBD
- Drugs e.g. phenytoin, valproate, trimethoprim
How may folate or B12 deficiency present? (7)
- Pallor
- Fatigue
- Anorexia
- Glossitis
- Developmental delay
- Hypotonia
- Severe cases: subacute combined degeneration of the cord with paraethesia of hands/feet
Where is the most common site of solid tumours in children?
Brain
70-80% of childhood brain tumours occur where? (2)
- Infratentorial (region containing the cerebellum)
2. Midline
What are the common types of brain tumours that occur in children? (4)
- Glial tumours
- Medulloblastoma
- Germ cell tumours
- Craniopharyngioma
What % of all childhood malignancies are brain tumours?
25%
How do infratentorial tumours present? (4)
- Raised ICP
- Headaches
- Vomiting
- Cerebellar ataxia
How does supratentorial tumours present? (4)
- Raised ICP
- Focal neurology
- Hypothalamic/pituitary dysfunction
- Visual impairment
Which age range is the most common for children to develop a brain tumour?
0-9 years
Which is the largest subgroup of brain tumours, accounting for 43% of all brain/CNS tumours?
Astrocytoma (a subgroup of the gliomas)
What % of astrocytomas are diagnosed as low grade?
76%
What is the name for a grade 1 astrocytoma? (also known as a low grade glioma)
Pilocytic astrocytoma
Why are they called pilocytic?
Because the cells are elongated and hair like
What are the characteristics of the grade 1 pilocytic astrocytomas?
They are slow growing, unlikely to spread and unlikely to return after being surgically removed
Where do pilocytic astrocytomas tend to grow?
In the cerebellum (but can also occur in the optic pathways)
Which condition is associated with pilocytic astrocytomas? - and what % of people with this condition will have one?
Neurofibromatosis type 1 (NF1) - affects 10%
In which location are the pilocytic astrocytomas associated with a higher mortality rate?
If they are located in the optic pathways - they are far less accessible, so harder to remove
What diagnostic imaging can be used to investigate brain tumours?
- CT (is quick and can be used in emergency situation)
2. MRI (better tumour definition)
What can be done to treat raised intracranial pressure? (3)
- Refer to paediatric neurosurgical unit
- Control tumour swelling with high dose steroids (usually dexamethasone)
- CSF drainage
Where are high grade gliomas typically located?
Supratentorial sites
In which age range are high grade gliomas more common?
Older children/teenagers
What is the median survival for a brainstem glioma?
<1 year
What is the name for the tumours that are high grade embyronal tumours, they are the most common malignant tumours, accounting for 15-20% of all childhood brain tumours?
Medulloblastoma
What is the age range most common for medulloblastomas to occur, and in which gender are they more common?
Ages 3 - 8, higher occurrence in males
What are the symptoms of a medulloblastoma? (6)
- Abrupt onset of headaches, especially in the morning
- Nausea/vomiting
- Feeling extremely tired
- Loss of balance and coordination
- Abnormal eye movements
- Blurry vision caused by swelling of the optic disc (papilloedema)
Where do medulloblastomas occur?
Cerebellum
Which genes are linked to brain tumours? (3)
- RB1 (retinoblastoma gene)
- NF1 and NF2
- TSC1 (tuberous sclerosis)
Which brain tumour is detected by finding an absent or abnormal light reflex?
Retinoblastoma
In addition to an absent light reflex, how else may a retinoblastoma present in terms of eye pathology? (2)
- Squint
2. Visual deterioration
When taking a paediatric history, what red flag questions are important to ask if suspecting cancer? (7)
- Fevers
- Night sweats
- Anorexia
- Weight loss
- Pallor
- Bruising
- Abnormal bleeding
What is the most common malignancy in childhood?
Acute lymphoblastic leukaemia (ALL)
Where does ALL arise from?
Malignant proliferation of ‘pre-B’ (B cell origin) most commonly, but can also arise from T-cell precursors.
What % of all childhood malignancies does ALL account for?
25%
What is the common age range that ALL presents in?
2-6 years
What are the signs that may be present in children with ALL? (9)
Normally a relatively quick onset of:
- Bone marrow expansion/lymphadenopathy
- Petechiae
- Testicular enlargement
- Gum hypertrophy
- Pallor
- Abdominal distension due to hepatomegaly/splenomegaly
- Tachycardia and flow murmur
- Airway obstruction
- Pleural effusion
What are the specific diagnostic tests for ALL?
- Bone marrow: morphology, immunophenotype, cytogenetics
- CSF : for cytospin
- Clinical examination: inappropriate swelling of testes in males
- CXR for mediastinal mass
What are the risk factors/genetic factors that can predispose a child to developing ALL?
- Dizygotic twins have a four-fold increase in risk of leukaemia compared with the general population
- Children with trisomy 21 have a 10/20 fold risk of developing ALL
- Other chromosomal disorders e.g. Fanconi’s anaemia
- ALL is concordant in 25% of monozygotic twins within a year of the diagnosis of the first twin
What is the link between infections and ALL in early childhood?
There is a protective factors in young children being exposed to infections from a young age - if they are insulated from common infections the immune system may respond in an abnormal way when they encounter them at an older age - babies who attend daycare appear to have a decreased risk of developing ALL
What are the symptoms of ALL? (11)
- Fatigue/dizziness/palpitations
- Severe and unusual joint/bone pain - limp
- Recurrent, severe infections
- High temperatures
- Left upper quadrant fullness
- Dyspnoea
- Headache, irritability, altered mental status, neck stiffness
- Frequent nosebleeds, spontaneous bleeding
- Unexplained weight loss
- Night sweats
- Pale skin
What are the differentials for ALL? (6)
- Infections - EBV, parvovirus B19
- Aplastic anaemia
- Lymphoma
- Metastatic cancer
- Osteomyelitis
- Juvenile idiopathic arthritis
What happens in ALL?
The bone marrow produces immature WBCs known as blast cells. As the number of blast cells increase, the number of RBCs and platelets decrease, causing symptoms of anaemia.
The blast cells are also less effective compared to mature WBCs, so more vulnerable to infections.
What is the four week induction treatment for ALL? (5)
- Steroids (dexamethasone) throughout induction
- Weekly IV vincristine
- IV L-asparaginase
- IV daunorubicin
- Intrathecal cytarabine and methotrexate
- aim is to kill the leukaemia cells in the bone marrow, restore the balance of cells in the blood and resolve symptoms
What is the second stage of the standard treatment for ALL?
Consolidation CNS-directed therapy - aim is to kill any remaining leukaemia cells in the CNS
What is the maintenance medication used to prevent the leukaemia returning?
- Daily 6-mercaptopruine (6MP), weekly oral methotrexate
- 4-weekly vincristine IV bolus and oral methotrexate
- 12 weekly IT methotrexate
-lasts for 2 - 3 years
What factors contribute to an adverse prognosis in ALL? (6)
- Male gender
- Age <2 years or >10 years
- High WCC at diagnosis
- Unfavourable cytogenetics e.g. philadelphia chromosome (t 9,22), AML1 amplification
- Poor response to induction and failure to remit by day 28
- High level of minimal residual disease
What is Burkitt’s type lymphoma?
Mature B-cell ALL
What is the overall survival of ALL with current treatment?
80%
What is leukaemia?
A malignant proliferation of white cell precursors which occupy the bone marrow. These blast cells can also circulate in the blood and deposit in various tissues.
What will a blood test of a child with ALL show?
Markedly raised WCC, anaemia, thrombocytopenia
What will testing of the bone marrow show in someone with ALL?
The bone marrow will be replaced with leukaemic lymphoblasts