CNS Tumours Flashcards
CNS tumours originating from glial cells?
- Astrocytoma
- oligodendroglioma
- ependymoma
- glioblastoma
CNS tumours originating from Primitive neuroectodermal cells?
- Medulloblastoma
- neuroblastoma
CNS tumours originating from Arachnoidal cells?
meningioma
CNS tumours originating from nerve sheath cells?
Schwannoma
neurofibroma
CNS tumours originating from lymphoreticular cells?
lymphoma
CNS tumours in children?
- astrocytoma
- medulloblastoma
- ependymoma
- others
CNS tumours in adults?
- glioblastoma
- meningioma
- astrocytoma
- schwannoma
- others
Epidemiology of CNS tumours?
Second commonest tumours in children and the sixth commonest in adults
Symptoms of CNS tumours?
Present with localising signs due to:
1. tissue destruction
2. non-specific effects of raised intracranial pressure
Locations for CNS tumours?
Adults?
Children?
- In children
- 70% are sited in the posterior fossa
- most are intrinsic tumors - In adults
- 70% are sited supratentorially
- intrinsic and extrinsic tumors both occur frequently
Metastatic tumours?
Metastatic tumors occur more frequently with increasing age: most are carcinomas
- which may form solid deposits in the CNS or spread by seeding in the CSF
Note: Survival depends on the age of the patient and the site, size and histology of the neoplasm
Pathogenesis of CNS tumours?
- Genetic
- Chemical & viral
- Radiation - ? Mobile phones
- Immunosuppression – primary cns lymphomas
- Trauma – role unproven
Brain tumors clinically present in what two main ways?
- Local effects – focal neurological signs
e.g. epilepsy or paraplegia - Mass effects – non specific signs & symptoms of space occupying lesion
> herniation being the common cause of death
Name intrinsic tumours?
- Astrocytoma
- Glioblastomas
- Oligodendroglioma
- Ependymomas
- Choroid plexus papillomas
- Hemangioblastomas
- Lymphomas
- Primitive neuroectodermal tumors
- Medulloblastoma
Epidemiology of astrocytoma?
10% of all primary adult CNS tumors, relatively more frequent.
Sites for astrocytoma?
Adults?
Children?
- cerebellum in children
- cerebral hemisphere in adults
Astrocytoma is classified according to?
- predominant cell type
- degree of differentiation
Prognosis for astrocytomas involve?
- degree of differentiation
- age of patient
- site & size
Microscopy of astrocytoma?
Epidemiology of glioblastoma?
30 % of all primary CNS tumors, rare in children
Location of glioblastoma?
Arise in white matter of cerebral hemispheres
- Dedifferentiate from pre-existing astrocytomas
Prognosis of glioblastomas depends on?
- degree of differentiation
- age of pt
- site & size
Microscopy of glioblastoma?
Epidemiology of medulloblastomas?
Commonest primitive neuroectodermal tumor
Location of medulloblastomas?
Arises in cerebellum of children
Pathology of medulloblastomas?
Rapid growth with extensive infiltration
resulting in obstructive hydrocephalus
CSF seeding common
Prognosis of medulloblastomas depends on?
With radiotherapy, prognosis has improved
5yr survival rate is 60%.
Microscopy of meduloblastoma?
Name extrinsic tumours?
- Meningioma
- Schwannoma
- Neurofibroma
Epidemiology of meningiomas?
18% of intracranial neoplasms in adults
Female>male 2:1
Sites of meningiomas?
parasagittal region, sphenoid wing, olfactory groove & foramen magnum
Macroscopy of meningiomas?
Smooth lobulated broadly adherent to dura
May infiltrate dura & bone, exceptionally invade brain
May markedly compress the brain
Histology of meningiomas?
Displays a variety of patterns
Occasionally malignant, and may metastasize outside the CNS
Metastatic CNS tumours?
CNS common site for metastasis
Hematogenous or direct spread
Carcinomas are the most common particularly from ; breast, bronchus, kidneys and colon , and malignant melanomas.
Often lodge at the boundary betwn grey & white matter.
Infiltration of subarachnoid space may produce carcinomatous meningitis
