Neuro Oncology: CNS Tumors and Lesions

Study Notes

CNS Tumors Below the Tentorium

Tumors originate from different types of glial and neuronal cells, commonly affecting children and adults.

Key Tumors in Children

Pilocytic Astrocytoma:
- Benign tumor arising in the cerebellum.
- Characterized by Rosenthal fibers and GFAP positivity.
Ependymoma:
- Malignant tumor typically located in the fourth ventricle.
- Associated with complications like hydrocephalus and pseudorosettes.
Medulloblastoma:
- Highly malignant tumor arising from neuroectodermal tissues in the cerebellum.
- Identified by small round blue cells and Homer-Wright rosettes.

Key Tumors in Adults

Glioblastoma Multiforme:
- Malignant, located in the cerebral hemispheres; crosses midline creating a "butterfly" appearance.
- Features pseudopallisading necrosis and is GFAP positive.
Oligodendroglioma:
- Malignant, often found in calcified frontal lobe white matter.
- Characterized by seizures and "fried egg" appearance of cells.
Meningioma:
- Generally benign, arises from arachnoid cells.
- Appears as a round mass attached to the dura mater, can be associated with seizures and contain psammoma bodies.
Schwannoma:
- Benign tumor of the 8th cranial nerve, located at the cerebellopontine angle.
- Characterized by S100 positivity, often associated with neurofibromatosis type 2 (NF2).

Additional Tumors

Ependymoma:
- Can occur in children or adults, typically in the fourth ventricle, leading to hydrocephalus.
Craniopharyngioma:
- Arises from Rathke's pouch near the optic chiasm, can cause bitemporal hemianopsia.

Description

Test your knowledge of Central Nervous System tumors and lesions, including astrocytomas, oligodendrogliomas, meningiomas, and more. Learn to identify and differentiate between various types of CNS tumors and lesions.