CNS Neoplasm

Question 1

Where do you most often find pediatric neoplasm vs adult neoplasm?

Answer 1

pediatric - 3:1 infratenorial (almost all primary)

adult - 3:1 supratentorial (75% primary)

Question 2

What are key clinical presentations of increased intracranial pressure?

Answer 2

vomiting ESPECIALLY with waking in the morning

blurred vision (check for papilledema)

headache

Question 3

how to tumors spread in CNS?

Answer 3

primary and metastatic tumors may spread WITHIN the CNS via CSF but primary CNS tumors never spread OUTSIDE the CNS

Question 4

what is a paraneoplastic syndrome?

Answer 4

most commonly caused by small cell carcinoma of lung… so a tumor in a different location creates effects in the CNS or PNS (ie autoantibodies formed from the tumor that cross react with nervous system)

Question 5

What are the 3 most common pediatric neuro neoplasms?

Answer 5

pilocytic astrocytoma
medulloblastoma
ependymoma

Question 6

Pilocytic astrocytoma

Answer 6

most often in cerebellum (causing ipsi limb ataxia and falling toward that side)

often presents in older childood…. survival usually more than 10 years

cystic lesion with mural nodule of tumor is often present – where the cyst wall is glial tissue and not neoplastic

Question 7

Medulloblastoma

Answer 7

incompletely differentiated fetal cells make it up resulting in a poorly differentiated neoplasm

often found in cerebellum in younger children (sonic hedgehog pathway problem)

solid tumor with “seeding throughout subarachnoid space”

-often travel in closely packed sheets, mitotically very active… gloomy prognosis

Question 8

ependymoma

Answer 8

Usually found in 4th ventricle

solid tumor that is arranged in patterns with true ependymal rosettes or perivascular pseudorosettes…

poor prognosis

Question 9

4 most common causes of adult neuro neoplasm (gliomas)

Answer 9

1) astrocytoma
2) oligodendroglioma
3) ependymoma
4) metastasis

Question 10

Infiltrating astrocytoma + glioblastomas (grading system)

Answer 10

accounts for 80% of adult primary brain tumors; most common in astrocytoma category

Grade II = diffuse astrocytoma - pleomorphic nuclei
grade III = anaplastic astrocytoma - plus mitotic activity
grade IV = glioblastoma (usually arise due to an amplification of epidermal growth factor receptor gene) - plus necrosis and/or vascular endothelial proliferation

Question 11

oligodendroglioma

Answer 11

often found in cerebral hemispheres

calcification is common

central nuclei and halo of clear cytoplasm (“fried-egg appearance”)

onset between 30-50 with slow growing tumors

Question 12

ependymoma

Answer 12

most often occur in the lateral ventricles

Question 13

Primary brain lymphoma

Answer 13

arises from B lymphocytes in the CNS

located deep in the cerebral hemispheres

signs/symptoms = headaches, seizures

*perivascular cuffing of tumor cells and diffuse infiltration of surrounding neural tissue

Most common CNS TOOMAH in immunosuppressed

Question 14

Germ cell tumors

Answer 14

origin = ectopic germ cells

usually in the midline, especially in pineal/suprasellar region (good prognosis actually)

Question 15

Meningiomas

Answer 15

often found attached to dura… does NOT invade adjacent brain tissue

psammoma bodies

more often affects women

often due to loss of chromosome 22 (NF2 gene)

Question 16

peripheral nerve sheath tumors (eg schwannoma)

Answer 16

origin = schwann cells in peripheral nerves

Most common site is the CN8 at the cerebello-pontine angle

Signs and symptoms = “acoustic neuroma” involving tinnitus, hearing loss, and vertigo.

Question 17

Tumors of Sellar Region (pituitary)

Answer 17

• *often present with endocrine problems**
• also present with CN3 or optic chiasm visual field deficits (ie bitemporal hemianopsia)

Pituitary adenomas are the most common… usually benign and slow growing

Craniopharyngioma - seprasellar epithelial tumor

Question 18

Metastatic Neoplasm characteristics/etiology

Answer 18

Incidence: about 50% of adult CNS tumors are metastatic..

Typically spread hematogenously from especially the breast and lung

typically well-demarcated but often cause widespread edema

prognosis = poor (usually only months)

Question 19

Neurofibromatosis type 1 (NF1)

Answer 19

autoDOM - one of the most common genetic disorders

often causes neurofibromas (benign nerve sheath tumors of the PNS) AND gliomas of the optic nerve

Question 20

Neurofibromatosis type 2 (NF2)

Answer 20

autoDOM

bilateral acoustic shwannomas and multiple meningiomas

Question 21

Tuberous Sclerosis

Answer 21

autoDOM

develop hamartomas and benign neoplasms involving the brain

Question 22

Von Hippel-Lindau Disease

Answer 22

autoDOM

hemangioblastomas occur = tumors developing in the CNS from a vascular origin (especially in cerebellum and retina)

cysts often form in other organs

higher chance of renal cell carcinoma and pheochromocytoma