CNS tumours

Question 1

Define

Answer 1

• Tumours of the central nervous system.
• NOTE: brain tumours cannot be truly differentiated into benign and malignant because supposedly ‘benign’ tumours can cause significant morbidity and mortality

Question 2

What are the types of high grade tumours?

Answer 2

o High-Grade = a tumour that grows rapidly and aggressively
• Glioma and glioblastoma multiforme
• Primary cerebral lymphoma
• Medulloblastoma

Question 3

What are the types of low grade tumours?

Answer 3

o	Low-Grade = a tumour that grows slowly and may or may not be successfully treated 
•	Meningioma
•	Acoustic neuroma 
•	Neurofibroma
•	Pituitary tumour
•	Craniopharyngioma
•	Pineal tumour

Question 4

Where do brain metastases commonly arise from?

Answer 4

• Lung
• Breast
• Stomach
• Prostate
• Thyroid
• Colorectal

Question 5

What are the risk factors?

Answer 5

o Ionising radiation
o Immunosuppression (e.g. HIV)
o Inherited syndromes (e.g. neurofibromatosis, tuberous sclerosis)

Question 6

Epidemiology

Answer 6

• Primary brain tumours = 2% of tumours diagnosed in the UK
• AIDS patients have an increased risk of developing CNS tumours
• Can develop at any age but are more common between 50-70 yrs

Question 7

What are the presenting symptoms?

Answer 7

• Presentation depends on the size and location of the tumour
• Headache (worse in the morning and when lying down)
• Nausea and vomiting
• Seizures
• Progressive focal neurological deficits
• Cognitive and behavioural symptoms
• Papilloedema

Question 8

What are the appropriate investigations?

Answer 8

• Bloods - check CRP/ESR to eliminate other causes (e.g. temporal arteritis)
• CT/MRI
• Biopsy and tumour removal
• Magnetic resonance angiography - define changing size and blood supply of the tumour
• PET
• NOTE: distant metastases are RARE with primary CNS tumours