NEURO - Brain tumours & raised ICP Flashcards Preview

► Med Misc 43 > NEURO - Brain tumours & raised ICP > Flashcards

Flashcards in NEURO - Brain tumours & raised ICP Deck (21):
1

Bimodal peaks of brain tumour epidemiology

–Peak in infancy and childhood
–Peak in 7th decade of life

2

Types of common brain tumours

•Neuroepithelial tumours (gliomas) 52%
-Astrocytoma (all grades) 44%
-Ependymoma 3%
-Oligodendroglioma 2%
-Medulloblastoma 3%

•Metastatic tumours 15%
•Meningioma 15%
•Pituitary adenoma 8%
•Acoustic neuroma 8%

3

Etiology of brain tumours

Environmental (ionising radiation, radiotherapy, nuclear explosions)

Genetic (Neurofibromatosis 1 & 2, Li Fraumeni syndrome)

4

(4) DDx of raised intracranial pressure with focal neurological deficits suggesting an intracranial mass enlarging over a few weeks

–Primary brain tumour
–Metastatic brain tumour
–Brain abscess
–Chronic subdural haematoma

5

Features of glioblastoma multiforme

Heterogeneous deep temporal mass with patchy contrast enhancement and areas of necrosis. (pallisading necrosis)

The optic radiation and internal capsule are compressed or invaded by the tumour

6

Describe malignant astrocytoma

•Gliomas comprise 50% of all brain tumours
•50% gliomas are malignant astrocytomas
–Glioblastoma multiforme (WHO grade 4)
–Anaplastic astrocytoma (WHO grade 3)

•6th-8th decade of life
•Eighth most common cause of cancer death
•Prognosis is dismal – median survival 7-14 months for glioblastoma multiforme

7

Features of malignant cells by pathology

—Hypercellularity
Cellular atypia/pleiomorphism
Nuclear atypia/pleiomorphism
Mitoses
Endothelial hyperplasia
Necrosis / pallisading necrosis

8

Px of intracranial mass

•Symptoms of raised intracranial pressure
•Seizures (40-80%)
•Focal neurological deficit: Depends on location of mass
•Duration of symptoms depends on rate of growth of mass
-Growth rate depends on grade of tumour
-Weeks to years

Increased ICP
–Headache
–Nausea and vomiting
–Drowsiness

9

What may cause increased ICP?

–Tumour mass
–Surrounding oedema
–Hydrocephalus if CSF pathways are blocked
–other extra volumes (bleeding)

10

Which lobe must be affected for dysphasia?

Dominant frontal or temporal lobe

11

Rx of malignant astrocytoma

•Commence steroids (dexamathasone)
–Reduction of cerebral oedema and ICP

•Resection of as much of the tumour as is safely possible
–If resection not possible then biopsy only

•Adjuvant therapy
–Radiotherapy and chemotherapy
–May be given in various combinations depending on the tumour grade

12

Features of a low grade glioma

Homogeneous mass best seen on FLAIR/T2-weighted MRI with no contrast enhancement and minimal mass effect

(c.f. heterogenous mass with patchy contrast enhancement in GBM; high grade glioma)

13

Describe a low grade glioma

•Includes oligodendroglioma, astrocytomas- and mixed forms
–WHO Grade 1 (usually children) and 2 (adults)

•Patients are young (25-45), neurologically intact, often only with seizures

•Survival is prolonged (years to decades)
–But eventual growth of low grade tumour or progression to a higher grade will occur

14

Rx of low grade glioma

–Removal of as much tumour as safely possible
–Often only a biopsy to avoid deficit
–Tissue diagnosis essential
–Defer radiotherapy and chemotherapy until tumour progression

Avoid SE as much as possible

15

What often causes intense cerebral oedema that causes more symptoms than the actual mass itself?

Metastatic brain tumour

Comprise approximately 15% of brain tumours in clinical series

Interval between diagnosis of primary tumour and brain metastases is highly variable

Common in cerebellum – may cause obstructive hydrocephalus

16

Commonest primary tumours that metastasise to the brain

Lung, breast, melanoma, kidney, GI (bowel)

17

Rx of brain metastases

•Commence steroids (dexamathasone)
–Reduction of cerebral oedema and ICP

•Surgery to remove the metastasis is indicated
–If the metastasis is solitary
–If the primary disease is stable and the patient has a reasonable life expectancy

•If the primary cancer is unknown the metastasis should be removed to confirm the diagnosis

•Occasionally one of multiple metastases will be removed for palliation
–If it is causing disabling symptoms, such as a hemiparesis, that can be improved by removal, even if the patient may only live a few months

•Whole brain radiotherapy (45 Gy)
–For multiple metastases
–After removal of a single metastasis (controversial)

•Stereotactic radiotherapy
–Single high dose focused radiation for 1 – 3 metastases

•Chemotherapy and targeted agents generally have poor penetration into the brain

18

Describe meningioma
- how common
- epidemiology
- origin of cells
- Px

•Most common benign brain tumour
•Most common in middle age
•More common in women than men
•Arise from arachnoid cells in the meninges
Slow-growing, therefore may reach a very large size
•Symptoms may be present for years
•May be asymptomatic and discovered incidentally

19

Characteristic locations of meningioma

on the dura
•Most common is falx, convexity and sphenoid wing
•Each location has a characteristic clinical syndrome
•Often associated with intense oedema

20

Pathology of meningioma

—“Whorls” are a common feature

Subtypes generally have no prognostic significance
—
A few subtypes portend a poorer prognosis
—
Malignancy is infrequent

21

Rx of meningioma

•Total surgical excision and obliteration of the dural attachment is the most effective treatment
•Subtotal excision and diathermy of the dural attachment if complete excision not possible
•Radiosurgery or radiotherapy for small, residual, recurrent or malignant tumours
•Extent of resection is related to risk of recurrence

Decks in ► Med Misc 43 Class (80):