neuro-oncology Flashcards
What are the risk factors of neuro-oncology?
- ionising radiation
- hereditary mutations e.g. li-fraumeni syndrome, NF type 1
What is the clinical picture of neuro-oncology?
- focal neurological deficits e.g. hemiparesis, hemiplegia
- gait disturbances if cerebellar involvement
- headaches
- clinical signs of increased ICP e.g. dilated pupils, bradycardia, vomiting
- possible seizures or personality changes (Depends on location)
- MRI or CT is a common diagnostic tool
What is a primary brain tumour?
- Primary brain tumors arise within the CNS - Are classified based on the growth characteristics and cell type from which the tumor arises
What is the growth characteristic classification of PBT?
Low grade : WHO grade I-II
Borders: well defined
Spreading potential: low
Recurrence: low
High grade: WHO grade III-IV
Borders: poorly defined
Spreading potential: high
Recurrence: high
What is the cell types PBT may arise from?
- glioma e.g. astrocytoma
- meningioma
- embryonal neuroectodermal e.g. medulloblastoma
- oligodendroglioma
What are the genetic characteristics of brain tumours?
- IDH mutation
- MGMT promotor methylation
- 1p/19q co-deletion
- TP53
What are the low grade gliomas?
- polycytic astrocytoma (grade 1)
- diffuse astrocytoma (grade 2)
Low grade gliomas mostly carries
IDH mutation or 1p/19q co-deletion
which carries better outcome
What are the high grade gliomas?
- Anaplastic astrocytoma (grade 3)
- Glioblastoma multiforme (grade 4)
What is a glioblastoma multiforme? mention also gliosarcoma
- GBM is a WHO grade 4
- most malignant CNS tumour with rapid growth
- affects elderly patients
- median survival 15 months
*gliosarcoma most highest degree of malignancy and aggressiveness in high grade gliomas with the worst prognosis
What is a polycytic astrocytoma?
- PA is WHO grade 1
- mostly in younger children < 20
- often associated with NF type 1
- slow growing a localised tumour
- found in cerebellum
- favourable long term survival
What mode of surgery is used for polycytic astrocytoma?
- fluorescein 5-ALA guided neurosurgery resection
ESMO guideline for high grade gliomas
Grade 3: anaplastic astrocytoma
Grade 4: Glioblastoma Multiforme
- Achieve maximal debulking resection
*assess molecular markers e.g. IDH mutation or 1p/19q co-deletion or MGMT methylation/non-methylation
- treat with temozolomide and RT for GBM
- RT or chemo for anaplastic astrocytoma
What is oligodendroglioma?
-low grade arising from oligodendrocytes
- anaplastic with IDH mutation 1p/19q mutation
- classic “fried egg” sign on biopsy
- Treated with resection and RT and chemo
What is an ependymoma?
- arises from ependymal cells
- affect younger population
- 4th ventricle is most common location in children
- biopsy shows classica “pseudorosettes”
- mostly supratentorial
- Tx with resection and RT
- usually poor prognosis
What is a medullablastoma?
- highly malignant tumour, primitive
neuroectodermal tissue - most common malignant pediatric tumour
- mostly in infratentorial, cerebellum, 4th ventricle
- Dropping metastasis along cranio-spinal axis
- Tx is resection, RT and chemo
- Tumour is highly radio and chemo sensitive