BRAIN TUMORS

Question 1

are the most common type of intracranial tumors in adults

Answer 1

Brain metastases of carcinomas (e.g., lung, melanoma, renal)

Question 2

_________ are benign, slow-growing tumors that arise from arachnoid cells. They are usually asymptomatic and found incidentally on imaging.

Answer 2

Meningiomas

Question 3

___________________________are benign tumors that arise from the Schwann cells of peripheral nerves. They are usually located in the cerebellopontine angle (infratentorial) because they primarily arise within the vestibular portion of the vestibulocochlear nerve (CN VIII). Symptoms depend on the nerves affected by the tumor (e.g., dizziness, hearing loss, facial nerve palsy)

Answer 3

Schwannoma

Question 4

_____________________-are highly malignant, rapidly progressive brain tumors that commonly manifest with nonspecific neurological symptoms. They are typically located in the white matter of the cerebral hemispheres (e.g., left temporal lobe), although they can cross the midline (butterfly). Gross hemorrhage, central necrosis, and microvascular proliferation are further pathological characteristics. On MRI, the tumor would appear as a ring-enhancing mass due to central necrosis. This kind of tumor is derived from from astrocytes.

Answer 4

Glioblastoma

Question 5

___________________are benign, slow-growing, highly vascularized tumors. They are typically located in the cerebellum (infratentorial), which is why symptoms often include cerebellar defects (e.g., ataxia). Features of increased intracranial pressure (e.g., headaches, vomiting) may occur if the tumor compresses the fourth ventricle. On gross pathological examination, these tumors appear red due to their high vascularity and they are often located within a cyst.

Answer 5

hemangioblastoma

Question 6

_ ________________are slow-growing tumors that arise from oligodendrocytes. While these tumors can manifest with the nonspecific neurological symptoms seen here, the disease course of this tumor is often much less rapid. Additionally, they are usually found in the frontal lobe. On gross pathological examination, they may show areas of necrosis.

Answer 6

Oligodendrogliomas

Question 7

tumor derived from astrocytes.

Answer 7

Glioblastoma

Question 8

This kind of tumor can occur sporadically or as a manifestation of Von Hippel-Lindau

Answer 8

Hemangioblastoma

Question 9

A disease resulting from the deletion of the VHL gene on chromosome 3, which encodes a tumor suppressor. Subsequently, activity of hypoxia inducible factor 1a is increased. VHL is associated with hemangioblastomas, bilateral renal cell carcinoma, pheochromocytoma, and renal/pancreatic cysts.

Answer 9

Von Hippel-Lindau

Question 10

These are commonly located in the infratentorial region, may present with features of increased intracranial pressure (e.g., headache, vomiting, blurred vision, papilledema). However, they are not associated with retinal vascular changes. Moreover, this type of tumor most commonly develops in early childhood. Histology typically shows perivascular pseudorosettes and rod-shaped blepharoplasts. This kind fo tumor is associated with Neurofibromatosis type 2.

Answer 10

Ependymoma

Question 11

The histopathologic findings of a cystic mass filled with dark, oily fluid (“motor oil-like”) confirm this diagnosis.

Answer 11

Craniopharyngioma

Question 12

_______________________________are derived from remnants of the Rathke pouch, which is an ectodermal outpouching of the pharyngeal roof that develops into the anterior pituitary gland. Compression of the optic chiasm by this tumor causes bitemporal hemianopsia and possibly, clumsiness or frequent tripping due to the visual field defect. Destruction of the posterior pituitary by the tumor results in central diabetes insipidus, which may present as increased urinary frequency.

Answer 12

craniopharyngioma

Question 13

Medulloblastomas, which are the most common malignant brain tumor in children, originate from the _____________________ and can cause clumsiness, frequent falls, and urinary symptoms

Answer 13

primitive neuroectoderm

Question 14

_____________________, which are the most common malignant brain tumor in children, originate from the primitive neuroectoderm and can cause clumsiness, frequent falls, and urinary symptoms

Answer 14

Medulloblastomas

Question 15

Homer Wright rosettes are associated with what?

Answer 15

medulloblastoma, primitive neuroectodermal tumors, neuroblastoma, pineoblastoma

Question 16

Arachnoid cells give rise to what tumor?

Answer 16

meningioma

Question 17

____________________are characterized on histopathology by layers of densely packed syncytial tumor cells, often arranged in whorls, interspersed spindle cells, and psammoma bodies.

Answer 17

meningiomas

Question 18

____________________arise from astroglial cells.

Answer 18

Astrocytomas

Question 19

S-100

Answer 19

S-100 is an immunohistochemical marker that identifies cells of neural crest origin. Tumors of neural crest origin that stain positive for S-100 include pheochromocytoma (from chromaffin cells), melanoma, schwannoma, and Langerhans cell histiocytosis.

100 swans a swimming

Question 20

Synaptophysin

Answer 20

Synaptophysin is an immunohistochemical marker that identifies tumors derived from neuronal cells, e.g., neuroendocrine cells, which contain numerous synaptic vesicles. Tumors that stain positive with synaptophysin include neurocytomas, medulloblastomas, small cell carcinomas of the lung, and carcinoid tumors. Neurons also stain positive for neurofilaments, which are part of the neuronal cytoskeleton.

Question 21

Glial fibrillary acidic protein (GFAP) is an immunohistochemical marker that would be able to identify what two brain tumors?

Answer 21

Astrocytoma and glioblastoma

Glial fibrillary acidic protein (GFAP) is an immunohistochemical marker that identifies cells of glial cell origin, which are non-neuronal cells of the central nervous system. Tumors of glial cell origin that stain positive for GFAP include astrocytoma and glioblastoma.

Question 22

In an 8 year old boy you have a CT scan of the head showing a supracellular cystic mass compressing the infundibular stalk. What tumor is it most likely?

Answer 22

craniopharyngioma. Any suprasellar lesion, including craniopharyngiomas, can compress the pituitary (infundibular) stalk, which can impede communication between the hypothalamus and the pituitary gland. This would likely lead to an increase in prolactin in this patient. Compression of this connection decreases the amount of dopamine delivery from the hypothalamus to the anterior pituitary gland. Dopamine normally inhibits the secretion of prolactin by the lactotroph cells. The loss of inhibition on lactotroph cells results in increased secretion of prolactin hormone (disconnection hyperprolactinemia). Increased prolactin levels would also decrease the levels of gonadotrophins (e.g., LH, FSH) by inhibiting GnRH release.

Question 23

Hypercellular areas of spindle cells and hypocellular areas of myxoid stroma are characteristic findings of ______________________________, a tumor arising from cells of neural crest origin, which explains why they stain positive for S100.

Answer 23

vestibular schwannoma, Schwann cells are of neural crest origin, which explains why vestibular schwannomas stain positive for S100.

Question 24

Whorls of densely packed cells with areas of lamellated calcification (psammoma bodies) suggest a ____________________.

Answer 24

meningioma

Question 25

Small blue cells arranged in rosettes around a central neuropil, known as Homer-Wright rosettes, suggest __________________________.

Answer 25

medulloblastoma

When he was a kid, Homer Wright took meds to mentally blast off

Question 26

Closely packed capillaries and stromal cells filled with lipid vacuoles suggest ______________________, a tumor of blood vessels that is often associated with von Hippel-Lindau disease.

Answer 26

hemangioblastoma

Question 27

Pleomorphic cells clustered around necrotic areas to form pseudopalisades suggest ____________________________, a malignant tumor of astrocytes.

Answer 27

glioblastoma multiforme (GM)

Question 28

Cells with clear cytoplasm and a central round nucleus resembling a fried egg suggest ____________________________

Answer 28

oligodendroglioma or pinealoma

Question 29

Calcifications and cholesterol crystals are typical histopathologic features of ______________________.

Answer 29

craniopharyngiomas

Question 30

What tumors may you find in the region marked A?

Answer 30

Glioblastomas, which are highly malignant brain tumors located in the white matter of the cerebral hemispheres. Rare tumor of childhood.

Question 31

What is the most likely tumor located at B?

Answer 31

oligodendroglioma, The frontal lobe is the most common location of oligodendrogliomas

Question 32

What tumor is likely to be located at the region C?

Answer 32

Craniopharyngiomas which are relatively benign tumors that are located above the sella turcica but may also expand into the sella. They arise from the remnants of Rathke pouch near the pituitary stalk. Craniopharyngiomas are the most common cause of hypopituitarism in children and have a bimodal age distribution with peaks at 5–14 years and 50–75 years of age.

Question 33

What tumor is likely to be at point D?

Answer 33

Pinealomas which are expected to arise from this region, which represents the pineal gland. The most common pinealoma in children is a germinoma, which would show undifferentiated germ cells on histology. Calcifications and cystic areas filled with cholesterol crystals, as seen in this patient, would not be expected.

Question 34

What is likely to be located at point E?

Answer 34

The cerebellum is a frequent location of pilocytic astrocytomas, the most common benign brain tumor in children. Histopathology would show microcysts, Rosenthal fibers, and GFAP positive staining, none of which are seen in this patient.

Question 35

What is likely to be located at F?

Answer 35

Medulloblastoma! The anterior cerebellum is a common location of medulloblastomas, the most prevalent malignant brain tumor in childhood. Histopathologic examination typically shows rosette-shaped small tumor cells (Homer-Wright rosettes). However, calcifications and cystic areas filled with cholesterol crystals as seen in this patient would not be expected. Medulloblastomas often extend into the 4th ventricle.

Question 36

What is likely to be located at G?

Answer 36

Ependymomas which typically arise from the floor of the 4th ventricle. Although calcifications and cystic areas may be present in biopsy, histopathologic examination would also show characteristic ependymal rosettes with perivascular pseudorosettes. Moreover, cholesterol crystals would not be expected in ependymomas.

Question 37

The eosinophilic, corkscrew-like processes seen on biopsy are called ______________

Answer 37

Rosenthal fibers

A collection of astrocytic processes that appear as eosinophilic, corkscrew-like fibers on histopathologic examination of pilocytic astrocytomas.

Question 38

Rosenthal fibers are findings of what kind of tumor?

Answer 38

Pilocytic astrocytoma

Question 39

____________________- is the most common pediatric primary brain tumor. It typically occurs in the cerebellum (posterior cranial fossa), but can also occur in supratentorial regions such as the optic nerve (optic glioma) and the cerebral hemispheres. Tumors in the posterior cranial fossa can present with dizziness, nausea, and clumsiness due to obstructive hydrocephalus and/or cerebellar damage.

Answer 39

Pilocytic astrocytoma

Question 40

________________________ are the most common supratentorial tumors in pediatric patients; they are typically in the suprasellar region and cause bitemporal hemianopsia or endocrine abnormalities (e.g., hyperprolactinemia, hypopituitarism).

Answer 40

Craniopharyngiomas

Question 41

Pleomorphic cells arranged in pseudopalisades are a hallmark of __________________________

Answer 41

glioblastoma multiforme

Question 42

Most common origins of brain mets

Answer 42

1. Lung
2. Breast
3. Melanoma
4. Renal
5. Colon