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 %)