Brain Tumors

Pathology of oligodendrogliomas is:

"Fried egg cells" with "chicken wire" vasculature, often calcified

Brain metastases are responsible for __% of cancer deaths

10-15 percent; Indicator of poor prognosis; Survival is usually <6 months due to systemic disease progression

Ependymomas are most commonly found in the __ ventricle(s)

4th ventrical

Pediatric brain tumors are typically __% posterior fossa; __% supratentorial

70% posterior fossa, 30% supratentorial (opposite in adults)

Gliomas account for >__% of malignant primary brain tumors. KNOW

80 percent!

Staging of astrocytoma is based on:

AMEN: Nuclear atypia, mitosis, capillary endothelial proliferation, necrosis (1=grade 2; 2=Grade 3; 3/4=Grade 4)

Pediatric Brain Tumors

Age-dependent presentation; Surgery can be curative; Hydrocephalus is common

Treatment of spinal cord metastases include:

Aggressive surgical resection (remove as much tumor as possible; immediate decompression, stabilize spine); Radiation--IMPROVES quality of life!

Supratentorial pediatric brain tumors:

Astrocytoma, germ cell tumors, ganglioglioma,....

Low grade oligodendrogliomas are often radiologically indistinguishable from ___

Astrocytomas (but more likely to be calcified; also better survival on avg)

Symptoms of spinal cord compression include:

Back pain or radicular pain (initial symptom); Motor weakness; Sensory loss; Autonomic dysfunction (urgency/incontinence; impotence)

Most common intracranial tumors are:

Brain metastases (10-30% of adults and 6-10% of kids with cancer); Rising incidence due to prolonged survival due to better systemic management and MRI's ability detect small asymptomatic metastases

How do you diagnose brain tumors?

CT (Sensitive but not specific); MRI (best imaging, more expensive); Histologic diagnosis (1. Stereotactic biopsy; 2. Open craniotomy and resection)

T/F: Brain tumors are not uncommon.

Cancer incidence of brain tumor is NOT in top 10; Somewhat more likely deaths in women.

Posterior fossa pediatric brain tumors:

Cerebellar astrocytoma; Brain stem astrocytoma; Medulloblastoma; Ependymoma

Tumors with deletions of ___ in oligodendroglioma typically respond to chemo and have better prognosis *KNOW*

Chromosomes 1p and 19q

Craniopharyngioma

Common suprasellar tumors of children and adults (bimodal distibution); Locally invasive, difficult to treat, unpredictable response, high morbidity

Prognosis of ependymomas is completely dependent on: *KNOW*

EXTENT OF SURGICAL RESECTION. Can radiate residual tumor; Chemoresistant

Ependymoma

Ependymal Cells

T/F: Meningiomas arise from the brain parenchyma

FALSE

T/F: Staging is used for brain tumors.

FALSE. No CNS lymphatic drainage; No concept of margins; Very rarely metastasize to lower organs.

Clinical presentation of brain tumors include:

Focal neurologic deficit; Seizure (focal/generalized, presenting symptom of 1/3 of brain tumors); Nonfocal symptoms (headache in morning, dementia, personality change, gait disorder)

Most common parenchymal brain tumor is:

Glioblastoma multiforme (GBM)

Gliomas are more common in (M/F), whereas meningiomas are more common in (M/F)

Gliomas=M; Meningiomas=F

Atypical meningiomas

Grade II: Increased cellularity and mitotic figures + brain invasion

No difference between Grade__ and ___ oligodendrogliomas.

Grade III and IV

Anaplastic meningiomas

Grade III: Sarcoma-like; Many mitoses and necrosis

Presenting symptoms of brain metastases include:

Headache, weakness, behavioral changes, seizures

Stereotactic biopsy is used for:

Inaccessible locations or debulking/chemo isn't appropriate; Drill hole in patient's head, stick a needle in the brain to get a sample

Only proven environmental cause of brain tumors is: *KNOW*

Ionizing radiation (X-irradiation)

Glioblastoma

Live 1 year; Diagnosed over 50 years; Always use MRI contrast; Plus endothelial proliferation/necrosis; Treatment: Surgery, radiation, chemotherapy

Anaplastic Astrocytoma

Live 3-4 years; diagnosed 3-50 years; Often do MRI contrast; Atypia plus mitoses; Surgery and/or radiation for treatment

Low Grade Astrocytoma

Live 5-10 years; Diagnosed 5-30 years; no MRI contrast; Nuclear atypia; Surgery or observation as treatment

Describe grading of Oligodendrogliomas

Low Grade (grade II); Anaplastic (grade III)

Grading of ependymomas is:

Low grade (II) and Anaplastic (III); both tend to occur in younger patients

Most common primary site of brain metastases is: *KNOW*

Lung cancer (50%). Often present without prior history of it.

GBM has a better response to chemotherapy if the enzyme MGMT is (methylated/unmethylated)

METHYLATED--inactivated! (Unmethylated--won't respond well)

Medulloblastoma

Malignant 4th ventricular tumor, seeds CSF pathways; Normal and high risk groups (Age, spread, degree of resection, pathology); ALWAYS require surgery + craniospinal radiotherapy + chemotherapy; Good 5 year survival

__ is the most likely to metastasize to the brain

Melanoma

Most frequent radiation-induced intracranial neoplasm is:

Meningioma

Unlike gliomas ___ are mostly GRADE 1 and LOW-GRADE but often large when detected

Meningioma

__ is the second most common primary brain tumor

Meningioma (originate from meningothelial cells that form the external membranous covering of the brain)

Most common radiation-induced neoplasm is __ *KNOW*

Meningioma. (Can also cause sarcomas and gliomas)

Schwannoma

Mislabeled acoustic neuroma; Most often in VESTIBULAR DIVISION of CN 8; Schwann cell origin; Surgical resection is curative

Glioblastoma Multiforme (GBM)

Most common primary brain tumor and most aggressive glioma; Least likely to respond to therapy; Median age: 62 years; Dichotomy in presentation: Younger patients have secondary GBM (tumor started as a lower grade that progressed from p53 mutations), whereas Older patients START with GBM (symptoms develop quickly)

Pilocytic Astrocytoma

Most common primary brain tumor in children; Hydrocephalus/mass effects symptoms; cured by surgical resection; Normal neurologic outcome and development common (benign tumor that can be in bad location)

Can cell phones cause brain tumors?

NO, but need more research for long term effects. CAN cause increased glucose metabolism!

Following the new onset of a focal seizure, it is important to consider:

Neoplasm/Brain tumor!

Gangliocytoma and ganglioglioma

Neurons

Oligodendroglioma

Oligodendrocytes

Schwannomas typically occur in (CNS/PNS)

PNS

Treatment of multiple brain metastases:

Palliative (whole brain radiation; stereotactic radiosurgery for >6 lesions)

Most common solid tumor of childhood

Pediatric brain tumors

Pathology of ependymomas are:

Perivascular pseudosettes

Astrocytoma

Pilocytic astrocytoma (grade I); Low Grade (grade II); Anaplastic astrocytoma (grade III); Glioblastoma (Grade IV

Pathology of Pilocytic Astrocytoma includes:

Piloid glial cells with rosenthal fibers

CT can miss structural lesions, particularly for:

Posterior fossa tumors OR non-enhancing lesions (low grade gliomas)

Most common secretor in pituitary adenoma is

Prolactinoma

___ almost never metastasize to the brain:

Prostate, esophagus, oropharynx, cervix

Craniopharyngiomas originate in:

Rathke's cleft/pouch

Third most common primary brain tumor

Schwannoma

A common presentation of low-grade oligodendroglioma is

Seizure

Pathology of medulloblastoma is:

Small blue-cell tumor, Homer Wright rosettes

Epidural spinal metatases

Spinal cord compression from metastases. Three patterns of spread: MOSTLY Epidural spread of hematogenous vertebral metastases (OR Extension from paraspinal space or hematogenous dissemination)

Typical pathology of meningioma is:

Spindle cells concentrically arranged in a whirled pattern; Psammoma bodies (laminated calcifications)

Pathology of schwannomas include:

Spindle-shaped cells in both loosely and densely-cellular foci

Pathology of craniopharyngioma is:

Stelloid "squamoid-type" epithelium, often calcified; cysts with motor oil fluid (cholesterol-rich)

Pituitary Adenoma

Suprasellar tumor; Bitemporal hemianopia from compression of optic chiasm (macroadenoma) OR endocrine abnormalities (microadenoma)

Treatment of pituitary adenoma includes:

Surgery (intracranial and/or transsphenoidal); Dopamine agonists (prolactinomas); Somatastatin analogs (growth hormone adenomas)

Treatment of solitary brain metastasis include:

Surgical resection as a possible cure and reduce mass effect; Gamma knife if no mass effect

T/F: Anaplastic oligodendroglioma has a better prognosis than for anaplastic astrocytoma

TRUE

T/F: Many meningiomas are asymptomatic and diagnosed at autopsy

TRUE

T/F: Brain Tumors may be histologically benign but biologically malignant

TRUE. Due to LOCATION (difficult to resect, compress vital structures); AND Infiltration of adjacent brain (subpial/subarachnoid spread, perineuronal or perivascular spread)

T/F: No known preventative strategies for Brain tumors

TRUE. Generally prognosis is poor.

Treatment of meningioma includes:

Total surgical resection (often curative but have recurrence risk--may need radiosurgery); If atypical meningioma or anaplastic, give radiosurgery!

Higher KI-67 Index levels indicate:

Worse outcome (Glioblastoma >10%; Low grade astrocytome <2 %)