Brain tumors 2
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14-Sep-2014 -
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Transcript of Brain tumors 2
CNS TUMORS
Metastatic tumors are more common than Primary tumors
Malignant CNS tumors rarely metastasize outside cranial cavity
Benign tumors can have devastating effects
Difference between Primary &Secondary Brain Tumors Poorly Circumscribed Single
Well circumscribed Multiple
Clinical features
Raised intracranial pressure Headache, nausea, vomiting Focal neurological signs weakness Seizures
Papilledema
Decreased strength in arm and leg
Brisk deep tendon reflexes
A ring-enhancing mass on CT scan
Gliomas
1. Astrocytomas
2. Oligodendroglioma
3. Ependymoma PNETs Medulloblastoma Non parenchymal tumors Meningioma
Classification
FREQUENY OF CNS TUMORS
Adults Astrocytoma( Glioblas
toma multiforme) Meningioma Schwanoma Ependymoma
Children Cerebellar
Astrocytoma Medulloblastoma
Ependymoma
Astrocytomas
1. Fibrillary astrocytic neoplasms Astrocytoma
Anaplastic astrocytoma Glioblastoma multiform
1. Pilocytic astrocytoma
Most Frequent Infiltrative growth Grade I - IV
Increased cellularity Nuclear Pleomorphism Mitotic activity Endothelial proliferation Necrosis - palisading
Fibrillary Astrocytic Neoplasms
Astrocytoma ,low and high grade.
Low grade. High grade.
A glioblastoma multiforme (GBM).
These neoplasms are quite vascular with prominent areas of necrosis and hemorrhage
pseudopalisading necrosis of neoplastic cells in a glioblastoma multiforme (GBM).
Tumors of the first two decades
Outer granular cell layer
Cerebellum
Disseminate through CSF
Small blue cell tumors with minimal differentiation if any
PNET (Medulloblastoma)
The irregular posterior fossa mass that is seen here near the midline of the cerebellum and extending into the fourth ventricle above the brainstem is a medulloblastoma. This is one of the "small round blue cell" tumors and it most often occurs in children.
microscopic appearance of medulloblastoma with small round blue cells.
Tumors of the adults Meningiothelial cells of arachnoid More in females Convexities of brain, olfactory groove,
lesser wing of sphenoid and spinal cord (thoracic segment)
Meningioma
Meningioma beneath the dura
Firm , indent (not invade) Note how this meningioma
beneath the dura has compressed the underlying cerebral hemisphere.
Swirling masses of meningoepithelial cells, spindle shaped cells with indistinct borders arranged in whorls or fascicles.
Whorls of polyhedral cells.
Schwannoma
Benign tumor of schwann cells Cerebellopontine angle and VIII nerve
(Acoustic neuroma) Tinnitus and sensorineural deafness Cells are immuno reactive for protein
S-100 Good prognosis
Schwannoma
It is a neurilemmoma which arises from the nerve sheath Schwann cells
Benign Associated with
Neurofibromatosis NF 2 gene mutation on chromosome 22
Well circumscribed, encapsulated, firm gray masses attached to nerve but can be separated
"Antoni A“ with hypercellular and scant stroma
Antoni B" pattern with a looser stroma, fewer cells.
Ependymoma
Benign 4th ventricle in children & lumbocasral spinal cord
in adults Obstructive hydrocephalus Perivascular pseudorosettes _ependymal cells
around vascular channels Recur after surgery and acquire more
aggressive behavior
The microscopic appearance of an ependymoma reveals a rosette pattern with the cells arranged about a central vascular space.
Oligodendroglioma
Type of glioma that are believed to originate from the oligodendrocytes
Perinuclear halo _ fried egg appaearance Slow growing recur after surgery and
degenerate into high grade gliomas overtime
High magnification micrograph of an oligodendroglioma showing the characteristic fried egg-like cells, with clear cytoplasm and well-defined cell borders.