Brain Tumours

Question 1

What is the epidemiology of brain tumours in childhood

Answer 1

Leading cause of childhood cancer deaths
Most common solid organ tumour in childhood
Majority are primary
60% infratentorial
Most cerebellum or posterior fossa

Question 2

What are the types of childhood CNS tumours

Answer 2

Astrocytoma (40%)
Medulloblastoma (20%)
Ependymoma (8%)
Brainstem glioma (6%)
Craniopharyngioma (4%)
Atypical teratoid/rhabdoid tumour

Question 3

Describe astrocytomas

Answer 3

Can be benign or highly malignant (glioblastoma multiforme)
Cerebellar
Most common is Pilocytic astrocytoma
- Common in neurofibromatosis (NF1)
- BRAF mutation present in 70% of cases

Question 4

What are the features of pilocytic astrocytoma on investigation

Answer 4

MRI: cerebellar, well-circumscribed, cystic, enhancing
Histopathology:
- Piloid (hairy) cell
- Rosenthal fibres and granular bodies
- Slow growing with low mitotic activity

Question 5

Describe medulloblastomas

Answer 5

Embryonal tumour: originates from neuroepithelial precursors
Arises in the midline of posterior fossa
Cerebellar
May seed through the CNS via the CSF
Up to 20% have spinal metastases at diagnosis

Question 6

Describe ependymomas

Answer 6

Mostly in the posterior fossa where it behaves like a medulloblastoma

Question 7

Describe brainstem gliomas

Answer 7

Malignant tumours associated with a very poor prognosis

Question 8

Describe craniopharyngiomas

Answer 8

Developmental tumour arising from the squamous remnant of Rathke pouch.
It is not truly malignant but is locally invasive
It grows slowly in the suprasellar region

Question 9

Describe Atypical teratoid/rhabdoid tumour

Answer 9

Rare type of aggressive tumour that most commonly occurs in young children

Question 10

What are the symptoms of brain tumours

Answer 10

Varies according to age, but usually:
Persistent or recurrent vomiting
Problems with balance, coordination or walking
Behavioural changes
Abnormal eye movements
Seizures (without fever)
Abnormal head position- wry neck, head tilt or persistent stiff neck

Infants: developmental delay/regression, irritability, lethargy, FTT, increase in head circumference/sutures/fontanelle
Children/adolescents: Persistent/recurrent headache (worse in morning.coughing), lethargy, blurred/double vision, deteriorating school performance, growth failure

Question 11

What are the symptoms of spinal tumours

Answer 11

Back pain
peripheral weakness of arms/legs
Bladder/bowel dysfunction

Question 12

What are the signs of a brain tumour in children

Answer 12

Raised ICP: disc oedema (papilloedema), obscuration of margins, elevation, venous congestion, haemorrhages
Cushing’s triad (late sign - likely to be coning by this time): Hypertension, bradycardia, deep breathing (pressure on the medulla)

Note: Papilloedema may be present but can be a late sign and difficult to detect

Question 13

What is the difference in presentation between intracranial, supratentoral and subtentorial brain tumours

Answer 13

Intracranial HTN: headache, vomiting, changed mental state
Supratentorial: focal neurological deficits, seizures, personality change
Subtentorial: cerebellar ataxia, long tract signs, cranial nerve palsies

Question 14

What investigations should be done for brain tumours in children

Answer 14

MRI
LP: ?CSF mets

Question 15

What is the management for brain tumours in children

Answer 15

MDTI: paediatrician, neurologist, SN, OT, PT, SALT, psychology, radiologist, oncologist, CLIC Sargent (Cancer and leukaemia in Children social worker)

Surgery: maximal safe resection
- Craniotomy (debulking)
- Open biopsies (inoperable but approachable)
- Stereotactic (open biopsy not indicated)

Radiotherapy and chemotherapy

Question 16

What are the complications of brain tumours

Answer 16

Children with brain tumours are at particular risk of:
- Neurological disability
- Growth, endocrine, neurophysiological and educational problems
due to potential site of the tumour, hazards of surgery and radiotherapy treatment given.

Question 17

What is a neuroblastoma

Answer 17

Arises from neural crest tissue in the adrenal medulla and sympathetic nervous system
Spectrum of disease from benign (ganglioneuroma) to highly malignant (neuroblastoma)
Can spontaneously regress in young infants

Question 18

What are the signs and symptoms of neuroblastomas

Answer 18

Pallor
Weight loss
Abdominal mass (or anywhere on the sympathetic chain from neck to pelvis) - Crosses the midline
Hepatomegaly
Bone pain
Limp
Rare symptoms: paraplegia, cervical lymphadenopathy, proptosis, periorbital bruising, skin nodules
Paravertebral tumour → spinal cord compression
>2yo: symptoms usually from mets (bone pain, BM suppression, malaise)

Question 19

What investigations should be done for neuroblastoma

Answer 19

CT/MRI
Urine catecholamine metabolites (VMA and HVA): high
Biopsy
BM sampling
MIBG scan: labelling of neuroblastoma cells with radioactive iodine

Question 20

What is the management for neuroblastoma

Answer 20

Some may resolve spontaneously
Localised primary: Cure with surgery
Metastatic disease: chemotherapy, high-dose therapy with Autologous stem cell rescue, surgery, radiotherapy (high risk of relapse)

Question 21

What is the prognosis for neuroblastoma

Answer 21

Most children presenting > 1 year of age present with advance disease and have a POOR prognosis
Cure rates for children with metastatic disease is around 40%
Amplification of the MYCN oncogene predicts aggressive behaviour