Neuro Oncology

Question 1

Are brain cancers common?

Answer 1

No, still one of the rarer cancers

17 out of 100,000

Question 2

What percentage of brain cancers are malignant?

Answer 2

55%

Question 3

How many types of brain cancers are there?

Answer 3

Over 150

Question 4

What are some examples of more common brain cancers

Answer 4

Meninges - meningiomas
Germ cells tumours - children
If of the brain substance itself - gliomas
Ependymal cells - ependymalomas
Tumour of cranial nerve VIII - acoustic neuroma
Lymphoma - primary CNS

Question 5

What are the 2 most likely areas that brain cancers are metastases from?

Answer 5

Lung

Breast

Question 6

How are brain tumours classified?

Answer 6

WHO classification:

Grade morphology 1-4 based on level of malignancy

Question 7

What is the prognosis for grade 1 tumours?

Answer 7

most of the time dont limit life

Question 8

What is the prognosis for grade 2 tumours?

Answer 8

oligodemdrogliomas - on average 7-10 year

Astrogliomas - on average 3-5 years

Question 9

What markers of low grade tumours indicate worse prognosis?

Answer 9

Weakness presentation rather than seizures
Fast growing tumours
Large tumours

Question 10

What is the prognosis for grade 3 tumours?

Answer 10

3.5 years

Question 11

What is the prognosis for grade 4 tumours

Answer 11

About 1 year

Question 12

What factors are taking into account during histological characterisation of tumours?

Answer 12

Cellularity/ mitotic activity/vascular proliferation/ necrosis

Question 13

What is the significance of molecular genetics in classification of tumours recently?

Answer 13

Were finding that sometimes grade 2 gliomas (classified by microscopy) would act like grade 4 in growth
Found that isocitrate dehydrogenase (IDH) gene can have mutations that cause the grade 2 tumour to act like a grade 4 and do a lot worse

Question 14

What causes brain tumours?

Answer 14

In the majority of cases no cause found
Ionising radiation - e.g. leukaemia 
Rare familial autosomal dominant genes:
Neurofibromatosis, tuberose sclerosis, Von HIppel-Lindau
Immunosuppression (HIV)

Question 15

What are some potential symptoms of brain cancers?

Answer 15

headaches
seizures
focal neurological symptoms
Other non-focal neurological symptoms

Question 16

What red flags with headache would suggest brain cancer?

Answer 16

Worse in morning, lying down, nausea, exacerbated by cough and sneeze

With focal neurological deficit

Question 17

How many people with a headache at GP have a brain tumour

Answer 17

1:1000

Question 18

How many people at GP have seizures as their symptom of brain tumour?

Answer 18

1:100

Question 19

Is focal neurological symptoms of brain tumours normally sudden or progressive?

Answer 19

progressive over days/weeks/months

Question 20

What is an example of a non-focal symptom?

Answer 20

Confusion

Question 21

What are the signs of brain cancer?

Answer 21

Papilloedema:
Optic nerve - should be crisp half moon shape, if blurred suggests high pressure in brain & needs urgent brain scan
Focal neurological deficit (likely high grade tumours):
Hemi-paresis
Hemisensory loss
Visual field defect
dysphasia

Question 22

What are the red flags for cancer?

Answer 22

Headache:
Raised intracranial oedema e.g. waking up in night, papilloedema
With focal neurological deficit
New onset focal seizure
Rapidly progressing focal neurology (wo headache)
Past history of cancer

Question 23

What are the main presentations for low and high grade cancers?

Answer 23

Low grade - typically present with seizures as pathways work around the tumour (can be incidental findings)

High grade - rapidly progressive neurological deficit. Symptoms of raised intracranial pressure

Question 24

What investigations would be warranted if brain cancer is suspected?

Answer 24

Imaging: ideally MRI (maybe CT with contrast)

Biopsy

Question 25

What is the low grade glioma scanning protocol?

Answer 25

Cerebral blood flow (if blue not much blood flow through tumour which is good) MR Spectroscopy (chemical composition - if similar to rest of brain that is good) Rate of growth Enhancement

Question 26

What is the reason for doing a biopsy?

Answer 26

to come up with diagnosis

Question 27

What are 2 key molecular markers checked for with brain cancer?

Answer 27

IDH | 1p19q co-deletion §

Question 28

What is the treatment for high grade tumours?

Answer 28

``` Steroids Reduce swelling Surgery Biopsy for diagnosis Resection to relieve intracranial pressure and prolong survival Radiotherapy Mainstay Chemotherapy Temozolamide - tablet that is relatively well tolerated PCV - bit more toxic ```

Question 29

What is the treatment for low grade tumours?

Answer 29

Surgery Early resection - mostly leaves cells behind and it will come back but prolongs survival Biopsy for diagnosis Radiotherapy alone Delays disease transformation not overall survival Radiotherapy and chemotherapy Evidence improves long-term survival Now give almost all low grade cancers PCV and radiotherapy Increases median overall survival time from 7.8 to 13.3 years - significant benefit

Question 30

What is the use of fMRI for cancer patients?

Answer 30

To help decide whether able to operate Get patient to do tasks and the areas with increased O2 flow will light up Often they have morphed around the tumour meaning you will be able to take the tumour out without causing too much damage

Question 31

Describe an awake craniotomy

Answer 31

Patient put to sleep, area of skull removed Wake patient back up and get to do functional tests, talking, moving, reading etc. Map out the brain until you get to the point where they stop, this is the limits for surgery This is useful as pathways move around due to tumours

Question 32

What is the difference in surgery results between awake craniotomy and surgery without mapping

Answer 32

Without mapping: 40% subtotal resection, 17% permanent deficits With mapping: 80% subtotal resection, 0.5% permanent deficits

Question 33

Are pituitary tumours benign or malignant normally?

Answer 33

Benign

Question 34

What are the symptoms of pituitary tumours?

Answer 34

Excessive or inadequate hormone production Local effects of tumour - vision (optic chiasm is above) Inadequate hormone production by the remaining pituitary gland