Primary Brain tumours

Question 1

What are the two types of specialised cells in the CNS?

Answer 1

(1. ) Nerve cells or neurons.
- Many types: eg; pyramidal, stellate, basket, Golgi, Purkinje, chandelier etc

(2.) Neuroglia: Astrocytes, Oligodendrocytes, Microglia

Question 2

Aetiology of brain tumours

Answer 2

(1. ) Most primary brain tumours are sporadic
(2. ) Genetic syndromes: neurofibromatosis or tuber sclerosis
(3. ) Secondary brain tumours usually derived from: Lung, breast, colorectal, testicular, renal cell, malignant melanoma

Question 3

How are brain tumours classified?

Answer 3

(1. ) TMN staging is not used. WHO Classification, Grade I-IV.
(2. ) Based on: histology of cells e.g. astrocyte, molecular markers, genetic factors

Question 4

What are Gliomas?

Answer 4

(1. ) Most common primary brain tumour
(2. ) Tumour of glial cells includes: astrocytoma, ependymoma, oligodendrocytoma

(3. ) Low grade gliomas = WHO grade I and II
(4. ) High grade gliomas = WHO grade III and IV

Question 5

Causes of gliomas (4)

Answer 5

• Majority no cause found
• Ionising radiation
• 5% Fx associated with: Neurofibromatosis, tuber sclerosis, Von Hippel-Lindau disease
• Immunosuppression

Question 6

Compare low and high grade glioma

Answer 6

LGG

• Slow growing but will undergo anaplastic (fast growing, abnormal) transformation
• Median age onset 35y
• Average survival 10y
• Signs and Sx = seizures, can be an incidental finding too

HGG

• 85% of malignant primary brain tumour
• Either as primary tumour or from pre-exisiting LGG
• Median age onset 45y (grade III), 60y (IV)
• Survival time: 3-5y (III), 12m (IV)
• Signs and Sx = rapidly progressive neurological deficits. Sx of raised ICP.

Question 7

Sx and Signs of primary brain tumours (6)

Answer 7

Depends on tumour type, grade, site

(1. ) Headache
- Woken by it, worse in morning, worse lysing down, associated with N&V
- Exacerbated by coughing, sneezing, drowsiness
(2. ) Seizures
(3. ) Focal neurological Sx
- Hemiparesis (weakness of one side of body)
- Hemisensory loss
- Visual field defect
- Dysphagia
(4. ) Non-focal Sx
(5. ) Papiloedema
(6. ) Raised ICP

Question 8

Urgent Referral when presented with headache

Answer 8

• Age >50y
• New/changed headache (inc frequency, severity etc)
• Neck stiffness
• Previous Hx of cancer
• Features of raised ICP e.g. papilledema and VIth nerve palsy
• Fever
• Focal neurology

Question 9

Investigations of primary brain tumours

Answer 9

(1. ) Imaging
- CT with contrast
- MRI (is better usually)
- Function MRI: For those with a confirmed cases of brain tumour

(2. ) Brain biopsy/surgery: when Dx is confirmed
- Histology, molecular, genetic markers

Question 10

Tx of primary brain tumours

Answer 10

Non-curative except for grade I. Prognosis for brain cancer 5y survival rate is 12%

LGG

(1. ) Surgery: resection
(2. ) Radiotherapy and early chemo

HGG

(1. ) Steroids: reduce oedema and swelling
(2. ) Surgery: biopsy or resection
- For diagnosis, relief of ICP, prolongation of survival
(3. ) Radiotherapy
- Mainstay of Tx
- Radical vs Palliative
(4. ) Chemo
(5. ) Awake Craniotomy with mapping