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 Gliomas Hemangioblastoma Meningioma Embryonal tumors Tumors of pituitary gland Craniopharyngoma Vestibular Schwannoma Germ cell tumors Lymphoma

Glioma Involve all lobes with preference to frontal & temporal lobes 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

PINEAL GLAND TUMOR pediatric brain tumors) than in adults (<1%) 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

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