Intracranial tumours Flashcards
How are the tumours classified?
WHO Classification 2007 Glioma: Astrocytic tumours Oligodendroglioma Ependymoma
Meningioma
PNET (medulloblastoma)
Nerve Sheath tumours:
Schwannoma, Neurofibroma
What are the microscopical features of astrocytic tumour?
Fine fibrillary and microcystic background
Increased cellular density
Pleomorphism ( variation in size, shape and chromasia)
What 4 markers are most relevant for the diagnosis of gliomas?
MGMT promoter methylation
1p/19q deletion
IDH1/IDH2 mutation
BRAF duplication/fusion
What are the treatment options for brain tumours?
Steroids Anti-epileptics Hormone replacement Surgery Radiotherapy Chemotherapy
What are the sign and symptoms of a brain tumour generally?
Pressure symptoms: headache (50%), Nausea and vomiting, confusion, reduced conscious level, blurred vision
neurological deficit - cognitive, visual, cranial nerve, motor, sensory
Seizures/epilepsy (50%)
Focal symptoms due to location (eg weakness, dysphasia)
In what cases would you do a scan on the brain?
Headache + neuro sign /symptom = Scan
What are the side effects of cranial therapy?
Acute effects (during or for a few weeks after RT)
- Cerebral oedema causing raised ICP & exacerbation of pre-RT neurological symptoms
- Hair loss
- Scalp/ear erythema (superficial reddening of the skin)
Intermediate effects (within a few weeks / few months) 1. Somnolence syndrome (severe tiredness) & exacerbation of existing neurological symptoms
Late effects (several months to years after RT) Damage to sensitive structures (shield these from the radiation as much as possible) e.g. lens (cataracts), pituitary (hypopituitarism), cerebral hemispheres (memory loss)
When is chemotherapy used in brain tumours?
Can be used palliatively
Can also be used to enhance the effectiveness of radiotherapy
What are the two most common types of brain tumours?
Gliomas (males)
meningiomas (females)
What are the microscopical features of glioblastoma tumour?
High cellular density and mitoses
Necrosis
Vascular proliferation
What are the microscopical features of pilocytic astrocytoma tumours?
note: common in children
Well-defined, cystic
Pilocytes
Rosenthal fibres
Vascular proliferation
What are the microscopical features of oligodendroglioma tumours?
Round uniform nuclei with clear cytoplasm (fried-egg appearance)
Arborising capillaries (chicken wire)
Calcifications
What are the microscopical features of ependymoma tumours?
Well-defined tumour, ventricles
Pseudorosettes - tumour cells collected around a blood vessel
Round small uniform cells
What are the microscopical features of ependymoma tumours?
Well-defined extra-axial tumour
Whorls - type of spiral or circular pattern
psammoma bodies - concentric lamellated calcified structures
What are the microscopical features of PNET (medulloblastoma) tumours? Who is it most common in?
Most common in children Very high cellular density Anaplastic hyperchromatic cells Frequent mitoses and apoptosis Rosette formation - red blood cells are arranged around a central cell to form a cluster that looks like a flower
