Intracranial & CNS Tumours Flashcards
What are symptoms of raised intracranial pressure?
- Headaches (early morning)
- Vomiting
- Blurred vision
What are the causes of raised intracranial pressure?
- Tumours
- Surrounding oedema
- Obstructive hydrocephalus
What neurological deficits are there?
- Motor
- Sensory
- Cranial nerve
- Visual
- Cognitive
What neuro causes are there for seizures?
- Supratentorial tumours
- Partial/complex partial/secondary generlaized
What investigations are used for suspected intracranial tumours?
- Haematological
- Tumour markers (PSA, Bhcg, aFP)
- Hormonal assay
- Visual fields
- CXR
What can an fMRI identify?
- Measures brain activity by detecting changes associated with blood flow
- Speech lateralised to left hemisphere
- Bilateral hand movements by bilateral motor cortex
How are intracranial tumours managed?
- Medical: steroids, anti-convulsants, hormonal replacement, anti-epileptics, radio/chemo
- Surgical: remove mass effect, biopsy (free hand, endoscopic, neuro-navigation, stereotactic), excision (total/partial)
- Adjuvant therapy
What is a frozen section?
- Confirm abnormal tissue
- Difficult to establish for some intrinsic tumours
- Oedema surrounding tumour may look abnormal
- Tumour resection can proceed
What are complications of surgery?
-Hydrocephalus- third ventriculostomy, ventricle-peritoneal shunt
What CNS tumours are most common in males & females?
M= gliomas
F=meningioma
What are the types of glial cells and what are their functions?
- Astrocytes (support & protect)
- Oligodendrocytes (myelin)
- Ependymal cells & choroid plexus cells (CSF)
- Microglia (defence)
What tumours can arise from nervous tissue?
- Glioma
- Meningioma
- Neurocytoma
- PNET
- Schwannoma
What is the histological criteria for malignancy in brain tumours?
- Cellular density & atypia
- Mitotic activity
- Necrosis
- Vascular proliferation
What are microscopic features of astrocytic tumours?
- Fine fibrillary & microcystic background
- Inc cellular density
- Pleomorphism
Describe the features of a diffuse astrocytoma and its grade
- 2
- Infiltrative, microcystic, fibrillary
- Low cellular density
- Mild atypia
- No mitotic activity
Describe the features of a anaplastic astrocytoma and its grade
- 3
- Moderate pleomorphism
- Mitoses
- Moderate cellular density
Describe the features of a glioblastoma and its grade
- 4
- Necrosis
- Vascular proliferation
- High cellular density & mitoses
Describe the features of pilocytic astrocytoma and its grade
- 1
- Well defined cystic
- Children
- Cerebellum
- Pilocytes
- Rosenthal fibres
- Vascular proliferation
Describe the features and grade of an oligodendroglioma
- 2/3
- Round uniform nuclei with clear cytoplasm (fried egg)
- Calcifications
- Arborising capillaries (chicken wire)
Describe the features and grade of an ependymoma
- 2/3
- Well defined
- Ventricles
- Pseudorosettes
- Round, small uniform cells
Describe the features and grade of a meningioma
- 1
- Adult females
- dura
- Well defined extra axial
- Whorls
- Psammoma bodies
Describe the features and grade of a PNET
- AKA medulloblastoma
- 4
- Children
- Cerebellum
- Very high cellular density
- Anaplastic hyperchromatic cells
- Rosette formation
- Frequent mitoses & apoptosis
Name some nerve sheath tumours
- Spindle-cell tumours
- Schwannoma (CN8, reticulin, biphasic pattern)
- Neurofibroma (spinal nerves rich in collagen)
What are the causes of:
- Meningioma
- Lymphoma
- NF1/2
- M=radiotherapy
- L=Immunosuppression
- NF1/2= Familial syndromes
What 4 markers are relevant for molecular diagnosis of gliomas?
- MGMT promoter methylation
- BRAF duplication/fusion
- 1p/19q deletion
- IDH1/IDH2 mutation
What are side effects of cranial radiotherapy?
- Acute= hair loss, scalp/ear erythema, cerebral oedema-raised ICP & exacerbation of neuro symptoms
- Intermediate= somnolence syndrome-severe tiredness & exacerbation of neuro symptoms
- Late= damage to sensitive structures-lens/cataracts, pituitary (hypopituitarism), cerebral hemispheres (memory loss)
In which tumour types can treatment be curative?
- Germ cell tumours
- Medulloblastomas
- Using chemo/radiotherapy, surgery or combination
