incidence and location of the major types of primary and

secondary brain tumors

• Tumors of the CNS can be:

Primary Secondary - benign or malignant tumors arise from various elements of the CNS

-tumors metastasize to CNS from many primary sources (lung, breast, kidney, GI tract, melanomma)

ADULT: Glioma Metastatic tumor Meningioma Pituitary Tumor Acoustic Neuroma

CHILDREN: Medulloblastoma(PNET) Astrocytoma Ependymoma Brainstem Glioma Craniopharyngioma Pineal Gland Tumor

Secondary tumors• most common type of brain tumor• may lodge to the following:• Brain parenchyma metastasis

– 5-40% of brain tumor, found in advanced age– cerebrum, cerebellum, brainstem– Usually found with disseminating systemic disease– Lung and breast – 2 most common metastasis to brain

• Leptomeningeal metastasis– Pia and arachnoid mater– Lymphoma – most common metastasis– 8% of patients with cancer

• Dural metastasis– Prostate CA for males and breat CA for females

Primary tumors

Glioma• Most common primary brain tumor• 50% of all symptomatic brain tumors• Incidence with advancing age• Can be located anywhere –cerebrum, cerebellum,

brainstem (pons)• Involve all lobes with preference to frontal &

temporal lobes• Types:

– Astrocytoma– Oligoendroglioma– Ependymoma

Glioma - Astrocytoma• Classification:

Pilocytic Astrocytoma

Grade I

Low Grade Astrocytoma

Grade II

Anaplastic Astrocytoma

Grade III

Glioblastoma Multiforme

Grade IV

Median Age 13 years 35-45 years 46 years 50-60 years

Incidence 2% of gliomas 5%-25% of gliomas

10%-30% of gliomas

45%-50% of gliomas

Location Cerebellum, Brain stem, Optic nerve, Cerebral hemisphere

Cerebral hemispheres (frontal 40%), pons thalamus, midbrain

Cerebral hemispheres, thalamus, midbrain, pons

Any region particularly cerebral hemispheres (frontal 40%)

Presentation Depending on site, inc. ICP, seizures, motor deficit

Seizures(65%), Incr.ICP, Mental status change, motor deficit

Seizures(50%), Incr.ICP,

Mental status change, motor deficit

Increased ICP, mental changes, motor deficit, seizures

Glioma - Oligodendroglioma

• 2-10% of all intracranial gliomas• Most often in 30-40 y/o• male:female = 2:1• Found primarily in cerebral hemisphere

(frontal, temporal,parietal often towards the midline) within brain parenchyma

Glioma - Ependymoma• More common in children

(0-20)• Located in 4th, 3rd and

lateral ventricle ventricle (most common in 4th ventricle)– Ataxia, vertigo, increased

ICP • Spinal lesions more

common in adults• Predominantly men

Meningioma • Second most common

primary tumor• 20% of all intracranial

tumors• Location: Parasagittal, falx,

convexity, entire cranial base, cerebellum, tentorium, rarely lateral ventricles

• Most diagnosed in 60 – 70y/o

• female:male = 2:1• 90% intracranial, 10%

intraspinal

Tumors of Pituitary Gland • 3rd most common primary brain tumor• Incidence 8-12%• Most common in adults (20-50y/o)• Located in sella region• .

Vestibular Schwannoma• Aka acoustic neuroma or acoustic neurofibroma• 4th most common tumor• 5-10% of intracranial tumor• Arises from schwann cells of vestibular branch of

CN VIII• Location: cerebellopontine angle (statoacoustic

nerve), base of the middle cranial fossa (trigeminal nerve)

• Peak age 40-60y/o• female:male = 2:1• Hearing loss, tinnitus, dysequilibrium

Lymphoma

• found in brain parenchyma• Usually develop in immunocompromised

individuals• Peak incidence 50-70y/o• male:female = 3:2• 98% B-cell tumors, 2% T-cell tumor

Hemangioblastoma

• 1-2% of intracranial neoplasms• Predominantly males• All ages are affected more frequently in young

and middle-aged adults• Predominantly in the cerebellum• Associated with polycythemia

Embryonal tumor – Primitive Neuroectodermal Tumor (PNET)

• Include a wide variety of tumors w/c seem to have common pathologic features suggesting origin from primitive neuroectodermal cells

• Medulloblastoma (most common), Retinoblastoma, Pineoblastoma, Neuroblastoma, Ependymoblastoma, etc

MEDULLOBLASTOMA-Accounts for 30%of all intra- cranial tumors in children & is the most malignant pediatric brain tumor

- Common in children (3%-8% of pediatric brain tumors) than in adults (<1%)- A variety of tumors may occur in this location, the most common is Germ cell tumors comprising 27%-30% of cases- Clinical manifestations: signs & symptoms of increased ICP, hydrocephalus, lethargy, memory disturbance, & in children seizures & increasing head circumference- Parinaud’s syndrome, precocious puberty

PINEAL GLAND TUMOR

- arise from anterior superior margin of the pituitary; are lined with stratified squamous epithelium-6-10% of intracranial tumor

CRANIOPHARYNGIOMA