Neuro - Pathology (Brain Tumors & Herniation Syndromes) Flashcards
Pg. 488-489 in First Aid 2014 Pg. 447-448 in First Aid 2013 Sections include: -Adult primary brain tumors -Childhood primary brain tumors -Herniation syndromes
What are 6 examples of adult primary brain tumors?
(1) Glioblastoma multiforme (grade IV astrocytoma) (2) Meningioma (3) Hemangioblastoma (4) Schwannoma (5) Oligodendroglia (6) Pituitary adenoma
What is another name for glioblastoma multiforme? Describe the tumor: Is it common or rare? Is it benign or malignant? What is the median survival of patients with it?
Grade IV astrocytoma; Common, highly malignant primary brain tumor with ~ 1 year median survival
Where in the brain is glioblastoma multiforme (grade IV astrocytoma) found? To where can it expand, what is that called?
Found in cerebral hemispheres. Can cross corpus callosum (“butterfly glioma”)
What stain is used in glioblastoma multiforme, and for what cells?
Stain astrocytes for GFAP.
Describe the tumor cells seen in glioblastoma multiforme (grade IV astrocytoma).
“Pseudopalisading” pleomorphic tumor cells - border central area of necrosis and hemorrhage.
Describe a meningioma: Is it common or rare? Is it benign or malignant?
Common, typically benign primary brain tumor
Where in the brain do meningiomas most often occur?
Most often occurs in convexities of hemispheres (near surfaces of brain) and parasagittal region
From what kind of cells does a meningioma typically arise? What is the involvement of brain parenchyma and dura?
Arises from arachnoid cells, is extra-axial (external to brain parenchyma), and may have a dural attachment (“tail”)
How does meningioma often present? What are other ways in which it might present?
Often asymptomatic; may present with seizures or focal neurological signs
What are 2 defining characteristics of meningioma on histology?
Spindle cells concentrically arranged in a whorled pattern; psammoma bodies (laminated calcifications).
What is the treatment/management in meningioma?
Resection and/or radiosurgery.
Where in the brain is hemangioblastoma most often found?
Most often cerebellar;
With what condition is hemangioblastoma associated, and in what clinical context?
Associated with von Hippel-Lindau syndrome when found with retinal angiomas
What substance can be produced by hemangioblastoma, and what result does this have?
Can produce erythropoietin –> secondary polycythemia
What characterizes hemangioblastoma on histology?
Closely arranged, thin-walled capillaries with minimal interleaving parenchyma.
Where in the brain is Schwannoma usually found?
Usually found at cerebellopontine angle
From what cell does a Schwannoma originate? What can be used to test this? What is a common example of Schwannoma localization and its result?
Schwann cell origin, S-100 (+). Often localized to CN VIII –> acoustic schwannoma (aka acoustic neuroma)
What is the treatment/management for schwannoma?
Resectable or treated with stereotactic radiosurgery.
In what condition are bilateral acoustic schwannomas found?
Bilateral acoustic schwannomas found in NF-2.
Is oligodendroglioma common or rare? Is it fast or slow growing?
Relatively rare, slow growing
Where is oligodendroglioma most often found?
Most often in frontal lobes
What describes the capillary pattern in oligodendroglia? How do its oliogodendrocytes appear on histology?
Chicken-wire capillary pattern. Oligodendrocytes = “fried egg” cells - round nuclei with clear cytoplasm.
What (imaging) finding is often present in oligodendroglioma?
Often calcified in oligodendroglia.
What is the most common pituitary adenoma?
Most commonly prolactinoma
What is the main clinical finding in pituitary adenoma, and why? What are 2 options for other sequelae with pituitary adenoma?
Bitemporal hemianopia due to pressure on optic chiasm. Hyper- or hypopituitarism are sequelae.
What are 4 examples of childhood primary brain tumors?
(1) Pilocytic (low-grade) astrocytoma (2) Medulloblastoma (3) Ependymoma (4) Craniopharyngioma
Describe the form/appearance of pilocytic (low-grade) astrocytoma.
Usually well circumscribed.
Where in children is a pilocytic (low-grade) astrocytoma most often found? What is another region in which it may be found?
In children, most often found in posterior fossa (e.g., cerebellum); May be supratentorial
What marker is positive in pilocytic (low-grade) astrocytoma?
GFAP (+)
Is pilocytic astrocytoma benign or malignant? What kind of prognosis does it have?
Benign; good prognosis
Name and describe the fibers that characterize pilocytic astrocytoma on histology. Briefly describe its gross apearance.
Rosenthal fibers - eosinophilic, corkscrew fibers; Cystic + solid (gross)
What kind of tumor is medulloblastoma, in terms of benign/malignant and location? What is an embryological connection to make to this tumor?
Highly malignant cerebellar tumor; A form of primitive neuroectodermal tumor
What condition can result from medulloblastoma, and why?
Can compress 4th ventricles, causing hydrocephalus.
How does medulloblastoma metastasize?
Can send “drop metastases” to spinal cord
What is the main histologic/gross finding to associate with medulloblastoma? How is medulloblastoma characterized on histology versus gross appearance?
Homer-Wright rosettes. Solid (gross), small blue cells (histology).
Where are ependymal cell tumors most commonly found? What complication can result from this?
Ependymal cell tumors most commonly found in 4th ventricle. Can cause hydrocephalus.
What kind of prognosis does ependymoma have?
Poor prognosis.
What 2 findings characterize ependymoma on histology?
Characteristic perivascular rosettes. Rod-shaped blepharoplasts (basal ciliary bodies) found near nucleus.
From where is craniopharyngioma derived?
Derived from remnants of Rathke pouch.
What kind of tumor is craniopharygioma? With what can it be confused, and why?
Benign childhood tumor, may be confused with pituitary adenoma (both can cause bitemporal hemianopia).
What is the most common childhood supratentorial tumor?
Craniopharyngioma
What (imaging) finding is common in craniopharyngioma? What is a descriptor for this finding?
Calcification is common (tooth enamel-like)
What are the 4 key herniation syndromes in neurology?
(1) Cingulate (subfalcine) herniation under falx cerebri (2) Downward transtentorial (central) herniation (3) Uncal herniation (4) Cerebellar tonsillar hernation into the foramen magnum
Draw a visual, including arrows and labels for the following key herniation syndromes: (1) Cingulate (subfalcine) herniation under falx cerebri (2) Downward transtentorial (central) herniation (3) Uncal herniation (4) Cerebellar tonsilar herniation into the foramen magnum.
See p. 489 in First Aid 2014
What is a significant vasculature concern in the context of cingulate (subfalcine) herniation under falx cerebri?
Can compress anterior cerebral artery
Where is the uncus located?
Uncus = medial temporal lobe
What 3 structures may be compressed in the context of uncal herniation? What effects does their compression have?
Compresses (1) ipsilateral CN III (blown pupil, “down-and-out” gaze), (2) ipsilateral PCA (contralateral homonymous hemianopsia), (3) contralateral crus cerebri (ipsilateral paralysis, “false localization” sign)
What is a significant complication of cerebellar tonsil herniation into the foramen magnum, and why?
Coma and death result when these herniations compress the brain stem (and inhibit respiration)
