Intracranial Neoplasms Flashcards
what is an extra-axial tumour
lesions that are external to the brain parenchyma
what is the most common type of extra-axial tumour
meningioma
what are features of meningioma tumours
usually benign tumors that arise from residual mesenchymal cells in the meninges
what are other extra-axial tumours
pituitary adenoma
craniopharyngioma
choroid plexis papilloma
acoustic neuroma (vestibular schwannoma)
what is a key fact about epidemiology of primary brain tumours
2nd most common seen in children
what are common Sx of a presentation of tumour
progressive neurological deficit motor weakness headache seizure vomiting mental changes papilloedema
what is headaches, vomiting, mental changes and seizures a sign of
increased ICP
what does blockage of CSF flow lead to
hydrocephalus
headache can only occur with raised ICP - true or false
false
can occur without raised ICP
what are worrying features of a headache
worse in morning; wakes them up worse on lying down worse with coughing/leaning forward worse on walking associated with vomiting gets better with vomiting
what do neurological signs depend on
tumour location
what is the frontal lobe responsible for
thought
reasoning
behaviour
memory
what is pre central gyrus responsible for
movement
what is post central gyrus responsible for
sensory
what is the temporal love responsible for
behaviour
memory
hearing & vision pathways
emotion
what is the parietal lobe responsible for
intellect
thought
reasoning
memory
what are the types of neuroepithelial tissue
Astrocytes Oligodendroglial cells Ependymal cells/ choroid plexus Neuronal cells Pineal cells Embryonic
what are the 4 gradings of astrocytic tumours
I - Pilocytic astrocytoma
II - Diffuse/Low grade astrocytoma
III - Anaplastic astrocytoma
IV- Glioblastoma
what are features of grade I astrocytomas
truly benign
slow growing
who commonly gets a grade I astrocytoma
children
young adults
what is the most common type of a grade I astrocytoma
pilocytic astrocytoma
what areas of the brain are pilocytic astrocytomas seen
optic nerve
hypothalamic gliomas
cerebellum
brainstem
Tx option for pilocytic astrocytoma
surgery
what are the sub types of Grade II astrocytomas (low grade)
fibrillary astrocytoma (most common) protoplasmic astrocytoma, gemistrocytic astrocytoma.
where do low grade astrocytomas often affect
temporal lobe
posterior frontal lobe anterior parietal lobe
where are the peak incidence for grade II astrocytomas
20-45y/o and 6-12y/o
what is the common presentation of grade II astrocytomas
seizures
headaches
what are poor prognostic factors for grade II astrocytomas
- age >50
- focal deficit (e.g. seizures)
- short duration of symptoms
- raised ICP
- altered consciousness
- enhancement on contrast studies
Tx for grade II astrocytoma
surgery +/- radiation
what is the median survival for anaplastic astrocytomas/grade III
2 years
when do grade III tumours commonly occur
40-50 y.o
older than low grade astrocytoma and younger than glioblastoma
anaplastic astrocytomas can progress into glioblastoma - true or false
true
what is the most common adult primary intracranial tumour
Glioblastoma multiforme
when is the peak age for a grade IV/glioblastoma
65-75 y/o
what is Glioblastoma multiforme associated with
NF type I
Turcot Syndrome
how does Glioblastoma multiforme spread
via white matter tracking/CSF pathways
particularly the corticospinal tract and corpus callosum
what is the corpus callosum
links the cerebral cortex of the left and right cerebral hemisphere
what is a glioma spreading to the callosum sometimes called
butterfly glioma”
1st line treatment of grade IV
surgery +/- chemo or radiotherapy
what are the 2 most common forms of glial tumours
Astrocytomas
Oligodendroglial tumours
what is the epidemiology of oligodendroglial tumours
- another type of glial tumour
- less common and account for 20% of glial tumours
- seen at age 25-45y/o and 6-12y/o
where do oligodendroglial tumours commonly affect
the frontal lobe
how to oligodendroglial tumours appear
greyish-pink
how are subarachnoid accumulations in oligodendroglial tumours described as looking
toothpaste morphology
what can help pathologist distinguish oligodendroglial tumours from astrocytomas
oligodendroglial tumours have:
- cysts
- peripheral calcification
- peritumoural haemorrhage
what are collision tumours
mix of oligodendroglial cells and astrocytic cells
what is the first line treatment for oligodendroglial tumours
Chemotherapy
are very chemosensitive
what can meningiomas originate from
arachnoid cap cells of the meninges
what are features of meningiomas
- most common extra-axial tumour
- usually benign
- rarely malignant or invade brain tissue
- produce Sx by compressing underling brain
what are meningiomas associated with
breast cancer
NF II
what are the 2 macroscopic forms of meningioma
globuse
meningioma en plaque
how do globuse meningioma apprear
rounded, well defined dural masses, looks like a fried egg (most common presentation)
how do meningioma en plaque appear
carpet or sheet-like lesions that infiltrate the dura and invade the bone with extensive regions of dural thickening.
where are common locations for meningiomas
parasagittal, convexity, sphenoid, intra-ventricular
what Sx might be seen in meningiomas
headaches
cranial nerve neuropathies
paresis
change in mental status
majority are asymptomatic
what is 1st Ix for meningioma
MRI head
what are the types of nerve sheath tumours
Vestibular Schwannomas
Neurofibromas
Malignant peripheral nerve sheath tumours (MPST)
where are Vestibular Schwannomas commonly seen
Cerebellopontine angle.
what causes Vestibular Schwannomas/acoustic neuromas
benign tumour of schwann cells in the vestibular portion of CN VII
what should be suspected in bilateral Vestibular Schwannomas/acoustic neuromas
NF type II
what reflex is loss in Vestibular Schwannomas/acoustic neuromas
corneal reflex
Sx of Vestibular Schwannomas/acoustic neuromas
hearing loss; asymmetrical commonly; (SNHL) dizziness facial numbness tinnitus loss of equilibrium
Ix of Vestibular Schwannomas/acoustic neuromas
1st - audiogram
2nd - contrast MRI
Tx of Vestibular Schwannomas/acoustic neuromas
1 - focused radiation or surgery
what is the most common germ cell tumour
germinomas
