Week 4- brain tumours Flashcards
How do brain tumours present (generally)?
Pressure on the brain causing
- progressive neurological deficit
- motor weakness
- headache
- seizures
What are the signs of increased intracranial pressure?
Headache Vomiting Mental changes Seizures (not mentioned in ppt but also papilloedema)
Masses can cause which types of herniation?
Subfulx- underneath the flax cerebri
Subtentorial- underneath the tentorium cerebelli
Uncul-
Tonsillar- herniation through the foramen magnum. Terminal.
What do uncal herniations cause?
Pre-terminal sign.
The parasympathetic fibres stop working and the oculomotor nerve becomes damaged. This causes an ipsilateral dilated pupil.
What are worrying signs of headaches?
Worse in the morning (CSF doesn’t drain as well lying down so the pressure in the head will already be more, if there is a mass it will be much more).
Worse on coughing/leaning forward.
May be associated and decreased with vomiting.
Why can compression of cranial nerve 6 be a sign of a space occupying lesion?
The abducent nerve has a long course through the brain and is therefore sensitive to shifts/changes. Anything that pushes on the brain from one side can cause this palsy. (presents as diplopia)
When should you worry for a brain tumour (three things in GP guidelines)
Headaches that wake you up at night.
Change in behaviour.
CHECK FOR PAPILLOEDEMA
Which tissues are most common causes of primary tumour in the brain
Astocytes
Oligodendroglial cells
Other less common- Ependymal cells/choroid plexus, neuronal cells, pineal cells, embryonic
Astrocytomas can be graded from I to IV. Give examples of each?
Grade I- Pilocytic, pleomorphic xanthoastrocytoma, subepydymal giant cell
Grade II- Low grade astrocytoma
Grade III-Anaplastic astrocytoma
Grade IV- Glioblastoma multiforme.
Describe the character and who is affected by grade I astrocytomas?
They are benign and slow growing. Mainly affects children and young adults.
Where do pilocyric astrocytomas arise?
Optic nerve, cerebellum, brainstem.
Hypothalmic gliomas
Treatment of choice for grade 1 astrocytomas?
Surgery- curative.
What signs might children with grade 1 astrocytomas start with?
Walking on their tip toes and vomiting. Then check for papilloedema
Examples of low grade astrocytomas?
Fibrillary, germinocystic, protoplasmic.
Where are you likely to get low grade astrocytomas?
Temporal lobe
Posterior frontal lobe
Anterior parietal lobe
How do low grade astrocytomas often present?
Seizures
Name some poor prognostic factors in low grade astrocytomas?
Age of over 50 Focal defecit Short duration of symptoms Raised ICP Altered consciousness Enhancement on contrast studies
Treatment of grade II astrocytomas?
Surgery +/- chemo, radio, combined.
What type of astrocytoma is a glioblastoma and how is it treated?
Grade IV
Needs surgery.
Which grades of astrocytomas are considered malignant?
Grades III-IV.
Name some examples of malignant astrocytomas?
Anaplastic astrocytomas (grade III) Glioblastoma multiforme
Prognosis of anaplastic astrocytomas?
2 years.
Describe a glioblastoma multiforme?
Most common primary brain tumour
Its spread is via CSF pathways and white matter tracking.
Prognosis is very poor (12-14months)
Treatment of malignant astrocytomas?
Non-curative surgery- only if it can increase survival quality.
Surgery- cytoreduction and reducing mass effect.
Post op radiotherapy
NOTE- astrocytomas are 80% of primary tumours.
Oligodendroglial tumours make up the other 20%.
:)
Where do oligodendroglial tumours likely arise?
Frontal lobes
Who do oligodendroglial tumours affect and how do they present?
25-45 year olds
Present with seizures.
Describe the gross appearance of oligodendroglial tumours?
Peripheral calcification
Cysts
Peritumoral haemorrhage
Oligodendroglial cells are low grade, true or false?
True however they are able to convert to malignancy.
How would you treat oligodendroglial tumours?
They are very chemosensitive- use procarbazine, lomustine and vincristine
Or you could do surgery with chemo. Surgery isn’t recommended in high grade ones.
A meningiomas is an example of a …. type of tumour.
Extra-axial- arising from outside of the brain parenchyma.
Which cells do meningiomas arise from?
Arachnoid cap cells. These are the cells that absorb CSF.
Majority of meningiomas are asymptomatic. T or F
True.
What other form of cancer can meningiomas be associated with?
Breast cancer
NF II
What is a meningioma en plaque?
The meningioma turns weird and can grow into bone.
Symptoms of meningiomas?
Headaches
Cranial nerve neuropathies (if on the skull base)
Regional anatomical disturbance
Describe the characteristics of meningiomas (how they grow, benign/malignant etc)?
Slow growing tumours (however tend to grow during pregnancy due to oestrogen surplus)
Benign in character
How are meningiomas classified?
Classic- meningiotheliomatous, fibrous, transitional)
Angioblastic
Atypical
Malignant
Which meningiomas are the aggressors?
CCRP (crap)
clear cell, chordoid, rhabdoid, papillary.
How would you treat meningiomas?
If they are small- leave them alone because the op isn’t worth the risk.
If not- consider surgery, radiotherapy and chemotherapy.
Three types of nerve sheath tumours?
Schwannomas (also known as neuromas)
Neurofibromas
Malignant peripheral nerve sheath tumours (MPST)
What are acoustic neuromas?
Vestibular schwannomas (8th cranial nerve)
How do vestibular shcwannomas present?
Hearing loss
Tinitus
Dysequilibrium
If they get really big they press on the 4th ventricle and can lead to hydrocephalus.
Treatment of acoustic neuromas?
If the patient has hearing- don’t do anything
Hydrocephalus management
Radiation treatment of choice- then surgery if unsuccessful.
What is the commonest problem after vestibular schwannoma surgery?
Facial nerve palsy (runs very close to the vestibular nerve)
Have to also check the corneal reflex. If the patient can’t blink they’ll develop corneal ulcers and may go blind.
What is the function of the pineal gland?
Diurnal regulation
Production of hormones
Who gets pineal gland tumours?
Tends to be children.
If you suspect a germ cell tumour, what blood tests would you do?
Alpha-feto protein- present in yolk sac tumours.
Beta HCG- present in choriocarcinoma and germinoma
Placental alkaline phosphatase (PFLAP)- present in germinoma
What is the function of a VP shunt?
Treats hydrocephalus
What test should you do in a suspected pituitary tumour?
Check the prolactin levels.