Cancers of the Central Nervous System Flashcards
What % of all cancers are brain tumours?
2-5%
What % of cancer deaths are caused by brain tumours?
2%
What is more common, primary brain tumours or mets to brain?
Mets
Where do mets to the brain commonly arise from?
- Lung
- Breast
- Skin (melanoma)
- Kidney
How can nasopharyngeal cancers spread to the brain?
They can extend directly through the foramina of the skull and involve the brain
What might meningeal metastases occur from?
- Leukaemia
- Lymphoma
- Breast cancer
- Small-cell lung cancer
- Local extension of medulloblastoma and ependymal gliomas
What % of CNS tumours occur in the spinal cord?
Less than 20%
Is the cause of most adult brain tumours known?
No
What can be associated with brain tumours that tend to occur in children or young adults?
Inherited phakomatoses
What inherited phakomatoses are associated with brain tumours in children and young adults?
- Tuberous sclerosis
- Li-Fraumeni syndrome
- Turcot syndrome
- Neurofibromatosis type I
- von Hippel-Lindau disease
- Gorlin’s basal naves syndrome
What specific brain tumours are associat4ed with von Hippel-Lindau disease?
I’m only joking we obvs don’t need to know this lol got u
What can the symptoms of glial tumours be divided into?
- General
- Focal
What causes the general symptoms of glial tumours?
Mass effects
What can mass effects cause in glial tumours?
- Increased ICP
- Oedema
- Midline shift and herniation
What symptoms can be produced by midline shift in glial tumours?
- Progressive altered mental state
- Personality changes
- Headaches
- Seizures
- Papilloedema
What do focal symptoms of glial tumours depend on?
The site of the tumour
What % of primary seizures are due to tumours?
Less than 10%
What % of supratentorial tumours present with seizures?
20%
How do meningiomas present?
- Headache
- Seizures
- Motor and sensory disturbance
- Cranial neuropathies (depending on site)
Where do meningiomas cause characteristic changes?
Plain skull radiographs
What are the characteristic changes on plain skull radiographs associated with meningiomas?
- Bone erosion
- Calcification
- Hyperostosis
Are meningiomas more common in men or women?
Women
What is the frequency of tumour sites in the spinal cord?
- 70% thoracic
- 20% lumbosacral
- 10% cervical
Where do spinal cord metastases most commonly occur from?
- Breast
- Lung
- Prostate
- Sarcoma
- Lymphoma
How do spinal axis tumours present?
- Sensorimotor dysfunction
- Radicular symptoms
- Syringomelia symptoms
What causes sensorimotor dysfunction in spinal axis tumours?
Cord compression
What causes radicular symptoms in spinal axis tumours?
Local extension of a tumour
What causes syringomyelia symptoms in spinal axis tumours?
Intra-medullary tumours causing central destruction
How do olfactory groove tumours present?
- Anosmia
- Visual loss
- Frontal lobe syndrome
- Papilloedema
How do sella turcica tumours present?
Visual field loss
How do posterior fossa tumours present?
- Ataxic gait
- Cranial neuropathies
- Cerebellopontine angle
- Suboccipital pain
- Hydrocephalus
- Ipsilateral arm and leg weakness
How do sphenoid wing tumours present?
- Exophthalmos and visual loss
- Temporal bone swelling
- Skull deformity
- Cavernous sinus syndrome
What can the types of brain tumours be divided into?
- Glial tumours
- Non-gliomas
What are the types of glial tumours?
- Gliomas
- Ependymomas
- Oligodendrogliomas
- Medulloblastomas
What % of brain tumours are gliomas?
50%
What can gliomas be graded as?
I-IV
What are ependyomas?
Cancers arising from ependymal cells lining the fourth ventricle
What are oligodendrogliomas?
Cancers arising from oligodendroglia
Who do medulloblastomas occur in?
Children
Where do medulloblastomas arise from?
Cerebellum
What might medulloblastomas be related to?
Neuroectodermal tumours elsewhere in CNS
Give 4 non-glial brain tumours
- Meningiomas
- Primary cerebral non-Hodgkin’s lymphoma
- Craniopharyngiomas
- Choroid plexus tumours
Give 4 types of primary spinal cord tumours
- Schwannomas
- Extradural meningiomas
- Intramedullary ependymomas
- Astrocytomas
What is the imaging of choice in brain tumours?
MRI with gadolinium enhancement
What might PET be useful for in brain tumours?
To help differentiate tumour recurrence from radiation necrosis
What is required to confirm the diagnosis of brain tumour?
Biopsy
When might a biopsy not be used to confirm the diagnosis of brain tumour?
Diagnosis is sometimes made on clinical evidence is made if biopsy is hazardous
Why is staging not applicable to most primary brain tumours?
As they are locally invasive and do not spread to regional lymph nodes or distant organs
What treatment is required for curing the majority of gliomas?
Surgery, radiotherapy, and chemotherapy
How much of a glioma should be removed at surgery?
Removal should be complete as possible within the constraints of preserving neurological function
What is the role of radiotherapy in glioma management?
Can increase cure rate or prolong disease-free survival in high-grade gliomas
May produce symptomatic improvement in patients with low-grade gliomas who relapse after initial therapy with surgery alone
What is the role of chemotherapy in glioma management?
May prolong disease-free survival in some types
What might limit the use of chemotherapy in gliomas?
Toxicity
What management do meningiomas require?
Surgical resection
What treatment is used for meningiomas that relapse after surgery?
Resect it again lol
What is the role of radiotherapy in meningiomas?
Reduces relapse rate
When should radiotherapy be considered in meningiomas?
- High-grade
- Incompletely resected
What are early complications of radiotherapy for brain tumours due to?
Reversible damage to myelin-producing oligodendrocytes
How long do oligodendrocytes damaged by radiotherapy take to recover?
3-6 months
What can radiotherapy induced damage to oligodendrocytes cause?
- Somnolence
- Exacerbation of existing symptoms in brain
- Lhermitte’s sign
What is Lhermitte’s sign?
Shooting numbness or parenthesis precipitated by neck flexion
When can radiotherapy cause Lhermitte’s sign?
When you’ve zapped the spinal cord
What are the late complications of radiotherapy for brain tumours?
Irreversible radiation necrosis
What causes irreversible radiation necrosis?
Damage to blood vessels
What might radiation necrosis mimic?
Disease recurrence
What does radiation necrosis correlate with?
Radiation dose
What % of patients receiving radiotherapy for brain tumours get radiation necrosis?
15%
How many roentgens gives you radiation necrosis?
- 6… not great, not terrible
p. s. this isn’t a real card
What do the prognostic factors for brain tumours depend on?
- History
- Grade and size of tumour
- Age and performance status of patient
- Duration of symptoms
