Cancer- brain Flashcards
what is brain cancer
- Consist of primary brain tumours which start in the brain; almost never spread
- Secondary; originated from other location and spread to brain
what is cancer?
Disease that results when cells undergo cellular change causing proliferation and uncontrolled growth of abnormal cells
aetiology of brain cancer
- True benign intracranial tumours mainly arise from the meninges (meningiomas), the pituitary gland (pituitary adenomas), and the myelin sheath of cranial nerves (neuromas or schwannomas)
- Primary Brain Tumour: arises from cells native to the Central Nervous System from the brain.
- Secondary Brain Tumour: growth in tissues outside the CNS and the spread to involve the brain
risk factors for brain cancer
- Age (young children and adults 40+)
- Gender (M)
- Environment exposure
- Family history (5%)
- Race and ethnicity (Northern Europe)
- Ionising radiation
- Head trauma
- Previous cancers
- Weak immune system (organ transplant patients, HIV AIDS)
clinical symptoms of brain tumours
- Headaches
- Seizures
- Mental status alterations
- Ataxia (trouble walking), nausea and vomiting
- Change in behaviour and personality
- Altered visual habits
epidemiology of brain tumours
-Secondary, or metastatic tumours are at least 3 times more common than all primary tumours combined.
-Generally common sites that cause secondary brain mets include: the lung, RCC, breast, melanoma and CRC
-Due to the likelihood of mets being found at the grey/white matter interface:
• 80% brain mets localise to cerebral hemispheres
• 15% to the cerebellum
• 5% to the brainstem
pathophysiology of brain tumours
- Within the brain, metastasis or secondary brain tumours are most commonly found in the area beneath the grey/white junction
- There are these areas classed as ‘watershed’, which are the zones on the border of major blood vessels (such as blood vessels of the COW)
- Emboli can get caught at these watershed areas as blood vessels are getting more peripheral and begin to overlap as they are getting smallers: where mets can start to develop
what will happen when investigating brain metastases
- Complete Blood Count
- Chest radiograph
- CT Brain +/- iodinated contrast
- MRI Brain
- PET Scan
- Biopsy (not usually needed if a primary cancer of another origin is known)
why do we do CT imaging for brain cancer and what will show
Often first line of imaging for acute neurological deficits
Post contrast scan will show a hypodense lesion
Easily accessible
Pre contrast scan will show signs of vasogenic oedema. The lesion could be isodense, hypodense or hyperdense
why do we do MRI imaging for brain cancer
Gold standard of imaging in Brain Metastases
Replaced CT in the 1980’s.
T1, T2, FLAIR and DWI
why do we do NM imaging for brain cancer
FDG PET:
- One of the best tools for imaging metastases however can only detect mets up to 1.5cm in size
- Lung, breast, colorectal, head and neck, melanoma and thyroid mets present usually as hypermetabolic
- Any central hypometabolism is suggestive of necrosis.
brain metastases treatment
- corticosteroids
- radiotherapy
- surgical therapy
- chemotherapy
what are gliomas
Glioma is an umbrella term used to describe a group of brain tumours that arise in the glial brain cells. Glioma encompasses: • Astrocytomas • Oligodendrogliomas • Oligoastrocytomas • Glioblastoma
what are glioblastomas
- Most common adult primary intracranial neoplasm. Generally very aggressive and have often poor prognosis (no longer than two years normally)
- Noteworthy feature of a GBM is that they can cross hemispheres using corticospinal tracts in the corpus callosum
- Spreads quickly and invades the brain with tentacle-like projections making it harder for resection
how do people with glioblastomas clinically present?
focal neurological deficit, symptoms of increased intracranial pressure & seizures
