Lecture 6: CNS Tumors COPY Flashcards
What 2 CNs do NOT originate in the brainstem?
CN1 and CN2
Smell and Sight
What are the symptoms of a CNS tumor based on? (3 processes)
- Functional areas of the brain involved
- Compression of adjacent structures
- Increased ICP
If a patient has a generalized symptomatic presentation due to CNS tumor, what is the most likley underlying pathological process?
Increased ICP
What is the MC manifestation of brain tumors?
Headache
Describe the HA that typically presents with CNS tumor.
- Non-specific
- Resembles tension or migraines
- Bifrontal, but increased pain on ipsilateral side
- Worsens with body position change or valsalva/coughing
- Pain at night or waking from sleep
Pain at night is due to the hypoventilation that occurs during sleep, causing increased CO2 and increased vasodilation.
What are the red flag symptoms regarding HAs?
- New onset in middle/old
- Change in prior HA
- Associated N/V
- Abnormal neuro exam
- Worsening with body position change
What suggests that emesis is neurologic in etiology?
- Triggered by body position change
- Presence of other things like HA or neuro deficits.
What kind of seizure is MC in primary tumors and mets?
Focal seizures
Specific symptoms are related to the lobe it affects.
What might occur to CPP with significant rises in ICP?
Decreased cerebral perfusion, leading to ALOC or syncope.
CPP = MAP - ICP
A tumor in what location of the brain might result in personality changes?
Frontal lobe
What clinical presentations might suggest a frontal lobe tumor?
- Personality changes
- Intellectual decline
- Difficulty focusing
- Expressive aphasia (Broca’s)
- Anosmia (Smell)
- Weakness
What clinical presentations might suggest a parietal lobe tumor?
- Sensory seizures
- Contralateral disturbances of sensation
- Written language interpretation
- Visuospatial deficit
What clinical presentations might suggest an occipital lobe tumor?
- Homoymous hemianopsia (loss of same side visual field in both eyes)
- Loss of color perception
- Prosopagnosia (can’t recognize familiar faces)
- Visual simultagnosia (can’t integrate a composite scene)
What clinical presentation might suggest a temporal lobe tumor?
- Seizures with olfactor or gustatory hallucinations
- Motor phenomena like lip licking
- Depersonalization, emotional changes, or behavioral disturbances
- Deja vu
- Auditory illusions or hallucinations
- Long-term memory impairment
- Lack of language comprehension (Wernicke’s)
Random words coming out the mouth in Wernicke’s aphasia
How do brainstem lesions typically present?
- CN palsies from 3-12
- Ataxic gait
- Nystagmus
- Altered reflexes
How does a brain tumor cause increased ICP?
- Large mass
- Restriction of CSF outflow, esp if close to 3rd and 4th ventricles
- Disruption of BBB causing angiogenesis and edema
What is the classic triad of increased ICP?
- HA
- N/V
- Papilledema
What are the 3 types of herniation?
- Subfalcial: occlusion of anterior cerebral artery causing frontal lobe infarction
- Transtentorial/uncal: compresses CN3, midbrain, and posterior cerebral artery.
- Cerebellar-foramen magnum/tonsillar: compresses medulla, causing apnea, circulatory collapse, and death
3 is the most dangerous herniation that could occur in someone with increased ICP
What is the preferred imaging modality for a CNS tumor?
MRI brain with contrast (gadolinium)
2nd is CT w/ con
What are the CIs to MRI?
- Metal implants
- Embedded devices
- Claustrophobic
It is a giant metal donut that your head sits in
What is MR spectroscopy used for?
Measures biochemical changes for tumors that aren’t enhanced on MRI w/ con
What is the first-line therapy for brain tumors?
- Dexamethasone to reduce cerebral edema
- Anticonvulsants only if hx of seizure
- If impending herniation, secure airway asap.
Preferred anticonvulsants:
levetiracetam, topiramate, lamotrigine, VPA, and lacosamide
What are the 4 types of CNS glial cells?
- Astrocyte: link neurons to blood supply (starlink)
- Oligodendrocytes: create myelin
- Ependymal cells: secrete CSF and beat their cilia to circulate the CSF
- Microglia: clear debris and dead neurons
What are glial cells?
Supportive cells around axons that DO NOT transmit any electrical impulse
What are the 3 types of malignant CNS tumors?
- Gliomas
- Medulloblastomas
- Primary CNS lymphomas
What is the benign CNS tumor?
Meningioma
Where do brain tumors usually appear from?
Mets.
- Lung cancer
- Breast
- Melanoma
- Renal
- Colorectal
What is the only risk factor for CNS tumors?
Ionizing radiation (not diagnostic radiation)
Immunosuppression for CNS lymphoma
How do you remember stage 3 and 4 WHO for primary CNS tumors?
- Grade 3: all the anaplastics
- Grade 4: all the blastomas
3 and 4 are treated identically.
What are the two types of PNS glial cells?
- Schwann cells: myelination and phagocytic
- Satellite cells: Surround and protect neuron cell bodies, regulate external environment, and provide nutrients.
Satellite cells are very vulnerable to inflammation and injury
What are the 3 types of gliomas?
- Astrocytoma (most aggressive: glioblastoma)
- Oligodendroglioma
- Ependymomas (MC in young children)
What are the 3 steps of treatment for Low grade gliomas (1-2)?
- Resect if possible; biopsy to confirm
- Determine risk factors: age > 40 or subtotal resection
- Monitor for relapse
1+ risk factor: radiation followed by chemo
0 risk factor: observe
For high grade gliomas, what is the management?
Grades 3-4
- Maximal safe resection with concurrent chemoradiotherapy
- Multidisciplinary approach
What is the main thing a CT CANNOT see that a MRI can for the brain?
Posterior fossa or small tumors
Posterior fossa includes cerebellum and brainstem
What is the MC malignant brain tumor in children?
Medulloblastoma, which originates in the posterior fossa
Cerebellar primitive neuroectodermal tumor (PNET)
How do you treat medulloblastomas?
- Resect
- Chemo
- Radiation therapy
What kind of lymphoma is primary CNS lymphoma?
Non-hodgkin’s
Associated with immunocompromised people.
What should we make sure to r/o in someone with suspected primary CNS lymphoma?
Toxoplasmosis via CSF
How do we manage a primary CNS lymphoma?
- Glucocorticoids once biopsy is obtained.
- Chemo
- Radiation therapy
What is the 2nd MC primary CNS tumor?
Meningiomas
Dura mater or arachnoid mater
What WHO grading is considered malignant for meningiomas?
Grade 3
What is the treatment for a small meningioma?
If < 2cm, conservative management with repeat MRI after 3-6 months.
What is the treatment for a grade 2 or 3 meningioma?
Wide resection
What are the MRI features that suggest metastatic CNS tumors?
- Multiple lesions
- Localization at the junction of the gray and white matter
- Circumscribed margins
- Large amounts of vasogenic edema compared to lesion size
You do NOT need to biopsy if lesion is metastatic appearing and pt has a primary cancer that is known to metastasize
What are the management steps for metastatic CNS tumors?
- Glucocorticoids
- Radiotherapy
- Chemo
- Palliative surgery
What are the 3 types of spinal cord tumors?
- Intramedullary: glioma (MC, specifically ependymomas)
- Intradural-extramedullary: meningiomas, nerve sheath tumors (schwannoma or neurofibroma)
- Extradural: probably metastatic
What S/S may suggest a spinal cord tumor?
- Localized pain that wakes nocturnally
- Sensory dysthesias and muscular weakness
- Bladder, bowel, and sexual dysfunction
- Progressive difficulty in ambulation
How do we locate a spinal cord tumor?
MRI spine w/ con
How do we manage a spinal cord tumor?
- Glucocorticoids
- Surgical decompression/removal
- Radiotherapy
What is the SPIKES protocol?
- Setup the interview
- Perception
- Invitation
- Knowledge
- Emotions
- Set goals
What are the 4 goals to keep in mind when delivering bad news to a patient?
- Discover what they already know
- Provide clear information that is within the boundary of what they know
- Support them emotionally
- Develop a treatment plan with their help
What are the MC cancers that metastasize to the spinal cord?
- Prostate
- Breast
- Lung
