pathology of brain tumours

Question 1

where are the 4 most common sites that a primary tumour can metastasize to the brain from?

Answer 1

lung- 35%
breast- 20%
kidney - 10%
GI tract - 5%

Question 2

how are brain tumours classified?

Answer 2

tissue of origin
location
primary or secondary
grading

Question 3

what is a GX grading for a CNS tumour?

Answer 3

grade cannot be assessed

Question 4

what is a G1 grading for a CNS tumour

Answer 4

well differentiated (low grade)

Question 5

what is a G2 grading for a CNS tumour?

Answer 5

moderately differentiated (intermediate grade)

Question 6

what is a G3 grading for a CNS tumour?

Answer 6

poorly differentiated (high grade)

Question 7

what is a G4 grading for a CNS tumour?

Answer 7

undifferentiated (high grade)

Question 8

what are some common ways that a brain tumour can present?

Answer 8

neurological deficit 68%
motor weakness 45%
mental status changes
seizures 26%
headache 54%

Question 9

what are some general signs and symptoms of brain tumours?

Answer 9

cerebral oedema
increased ICP
focal neuro deficits
obstruction of CSF flow
pituitary dysfunction
papilloedema

Question 10

what are some signs and symptoms that are specific to cerebral tumours?

Answer 10

headache
vomiting NOT related to food intake
changes in visual fields and acuity

hemiparesis or hemiplegia
hypokinesia
decreased tactile discrimination
seizures
changes in personality or behaviour

Question 11

what are som signs and symptoms more specific to brainstem tumours?

Answer 11

hearing loss
facial pain and weakness
dysphagia, decreased gag reflex
nystagmus
hoarseness
ataxia
dysarthria

Question 12

what are some signs and symptoms more specific to cerebellar tumours?

Answer 12

disturbances in coordination and equilibrium

Question 13

what are some signs and symptoms more specific to pituitary tumours?

Answer 13

endocrine dysfunction
visual deficits
headache

Question 14

what are some signs and symptoms more specific to frontal lobe tumours?

Answer 14

inappropriate behaviour
personality changes
inability to concentrate 
impaired judgement
memory loss
headache
expressive aphasia
motor dysfunctions

Question 15

what are some signs and symptoms more specific to parietal lobe tumours?

Answer 15

paraethesia
loss of 2 part discrimination
visual field deficits

Question 16

what are some signs and symptoms more specific to temporal lobe tumours?

Answer 16

psychomotor seizures
hallucinations
loss of consciousness without convulsions

Question 17

what are some signs and symptoms more specific to occipital lobe tumours?

Answer 17

visual disturbances

Question 18

what are some classifications of intra axial tumours?

Answer 18

gliomas
oligodendroglioa
ependymomas
medulloblastoma
CNS lymphoma

Question 19

what are 3 types of glioma?

Answer 19

astrocytoma
anaplastic astrocytoma
glioblastoma multiforme

Question 20

where do ependymomas originate from?

Answer 20

lining of the ventricle

Question 21

what types of patients are CNS lymphomas common in?

Answer 21

immunocompromised patients

Question 22

what are some classifications of extra axial tumours?

Answer 22

meningioma
metastatic
acoustic neuromas
pituitary adenoma
neurofibroma

Question 23

what do meningiomas arise from?

Answer 23

arachnoid cap cell types from the arachnoid membrane

Question 24

are meningiomas usually non invasive?

Answer 24

yes

Question 25

where are some common locations for meningiomas?

Answer 25

parasagittal region sphenoid wing parasellar region

Question 26

how do meningiomas present?

Answer 26

asymptomatic focal or generalized seizure gradually worsening neurological deficit

Question 27

what is a defining characteristic of meningiomas when contrast is increased on MRI and CT?

Answer 27

they become enhanced with contrast

Question 28

do diffuse low grade astrocytomas infiltrate surrounding tissue?

Answer 28

yes, widely

Question 29

where in the brain do diffuse low grade astrocytomas present?

Answer 29

frontal region in the subcortical white matter

Question 30

how do diffuse low grade astrocytomas present?

Answer 30

seizures headaches slowly progressive neurological deficits

Question 31

do diffuse low grade astrocytomas enhance with contrast when imaged?

Answer 31

not usually

Question 32

what is more sensitive when attempting to stage a diffuse low grade astrocytoma - CT or MRI?

Answer 32

MRI

Question 33

how does a glioblastoma infiltrate?

Answer 33

along white matter (can cross the corpus callosum)

Question 34

where do glioblastomas present?

Answer 34

frontal and temporal lobes | basal ganglia

Question 35

how do glioblastomas present?

Answer 35

seizures headache slowly progressive neurologic deficits

Question 36

what are some features of a glioblastoma when viewed on a CT?

Answer 36

hypodense/isodense central hypodense area of necrosis surrounded by thick enhancing rim surrounding oedema

Question 37

how are oligodendrogliomas distinguished from astrocytomas?

Answer 37

"fried egg" appearance

Question 38

what do oligodendrogliomas arise from?

Answer 38

myelin

Question 39

where are oligodendrogliomas located?

Answer 39

superficially in frontal lobes

Question 40

how do oligodendrogliomas present?

Answer 40

seizures most common headache slowly progressive neurologic deficits

Question 41

how do oligodendrogliomas look on a CT?

Answer 41

well circumscribed, hypodense lesions with heavy calcification cystic degeneration of common but haemorrhage and oedema are uncommon

Question 42

what are some features of a CNS lymphoma?

Answer 42

B lymphocytes increased ICP brain destruction

Question 43

what can cause haemorrhagic brain mets?

Answer 43

melanoma renal cell choriocarcinoma

Question 44

what are some imaging modalities that can be used to diagnose brain tumours?

Answer 44

``` CT scan with/without contrast MRI with/without contrast plain films myelography PET scan ```

Question 45

what kind of tumours might a CT scan miss?

Answer 45

small tumours brain stem tumours low grade astrocytomas tumours adjacent to bone

Question 46

what are some post op complications that may arise from removal of a brain tumour?

Answer 46

``` raised ICP hypovolemic shock hydrocephalus atelectasis pulmonary oedema meningitis CSF leak seizures ```