Tumors Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

MC extra-axial neoplasm of the brain?

A

meningioma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What percentage of meningiomas occur supratentorially?

A

90%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

MC locations for meningioma outside of the CNS?

A

sinonasal cavity, parotid gland, deep (neck) tissues, skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

CT characteristics of meningioma?

A

60% are hyperdense, 20% have calcification.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the “cleft” sign?

A

The “cleft sign” has been described in MR to identify extra-axial intradural lesions such as meningiomas. The cleft usually contains one or more of the following: (1) cerebrospinal fluid (CSF) between the lesion and the underlying brain parenchyma, (2) hypointense dura (made of fibrous tissue), and (3) marginal blood vessels trapped between the lesion and the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How often do meningiomas show a “dural tail”?

A

72% of the time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Top differential considerations for a meningioma?

A

the typical situation is a differential diagnosis of vestibular schwannoma, or fifth nerve schwannoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Intraosseous menengioma may resemble what other neoplastic process?

A

Blastic osseous mets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Intraventricular meningiomas typically occur where?

A

Intraventricular meningiomas typically occur around the choroid plexus (80%) in the trigone of the lateral ventricle and have a distinct propensity for the left lateral ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Intraventricular meningiomas calcify how often and in what age group are they more often found?

A

Intraventricular meningiomas calcify in 45% to 68% of cases, and their frequency is higher in children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Multiple meningiomas are associated with what?

A

neurofibromatosis type 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How often are bony changes seen with meningioma, and where?

A

20% to 46% of cases. Hyperostosis is particularly common when the tumor is at the skull base or
anterior cranial fossa, and here it may resemble fibrous dysplasia or Paget disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Role of angiography and appearance with meningioma?

A

Meningiomas diagnostically appear as lesions with an angiographic stain (tumor blush) and have both dural and pial blood supply.

The characteristics of the stain are classically compared with an unwanted guest who comes early
and stays late.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Features of malignant meningioma?

A

usually diagnosed when a meningioma exhibits intraparenchymal invasion or markedly rapid growth have restricted diffusion compared to benign meningiomas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Are hemangiopericytomas more common in men or women?

A

Men, unlike most meningiomas which are more common in women.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Location of hemangiopericytomas?

A

They tend to be large (over 4 cm in size), lobular, and extra-axial supratentorial masses. Hydrocephalus, edema, and mass effect are not uncommon with this entrée.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Features of melanocytoma?

A

usually presents as a posterior fossa mass. Hyperintensity on T1WI is the only hope for sealing this
diagnosis, but the presence of this finding varies with melanin content. Spread of melanocytosis through the Virchow-Robin spaces is possible.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are “the three” neurogenic tumors?

A

schwannomas, neurofibromas, and neuromas - all similar in appearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What finding is associated with vestibular schwannomas 7-10% of the time?

A

arachnoid cyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Schwannoma or Meningioma brighter on T2?

A

Schwannoma much more often than Meningioma. (due to cysts and/or Antoni B tissue)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Important finding in schwanoma not seen in meningioma related to effect on adjacent bony structure?

A

The porus acusticus (the bony opening of the IAC to the cerebellopontine angle cistern) is typically flared and enlarged with vestibular schwannomas, whereas the amount of tissue seen in the IAC with meningiomas is usually small or absent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Top differential for a jugular foramen tumor? How do you differentiae the two?

A

Jugular schwannomas more commonly grow intracranially than extracranially and typically smoothly erode the jugular foramen. The border of the bone is sclerotic, as opposed to the paraganglioma, which has a much more irregular and nonsclerotic margin. Schwannomas compress the jugular vein, whereas paragangliomas (glomus jugulare tumors) invade the vein. Growth into the posterior fossa is the rule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are nueromas and where do they occur?

A

By strict pathologic definition neuromas refer to a posttraumatic proliferation of nerve cells rather than a true neoplasm. They are usually seen in the cervical spine when nerves are avulsed or in an operative bed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What primarys cause dural metastases?

A

Lung, breast (MC), and prostate cancer, as well as

melanoma, are known to produce dural metastases. Lymphoma too, but may be primary in the dura

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

In children dural metastases are most commonly associated with what primary?

A

adrenal neuroblastomas and leukemia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Inflammatory lesions that may simulate dural metastases?

A

granulomatous infections (mycobacterial, syphilitic, and fungal), Erdheim-Chester disease, sarcoidosis, and Langerhans cell histiocytosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Apprearance of subarachnoid seeding?

A

Usually one sees tiny nodules of implanted tumor seedings.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

When subarachnoid seeding is diffuse it is termed what?

A

“sugarcoating” of the subarachnoid space because the whole pial surface is studded with sugar granules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

most common tumors to seed the CSF?

A

Lymphoma and leukemia
(However, because they only rarely invade the meninges and do not incite reactions in the CNS, lymphomatous clusters are infrequently identified by neuroimaging techniques; the diagnosis is usually made by multiple spinal taps for CSF sampling)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the appearance of CSF on FLAIR with malignant involvement?

A

The malignant cells in the CSF or the associated elevated protein in the CSF will cause the usually low signal of CSF to be bright on a FLAIR scan. Although this may be a difficult diagnosis to make in the basal cisterns where “f ” (FLAIR and flow) artifacts abound, the presence of such high signal over the convexities implies subachnoid seeding, subarachnoid hemorrhage, or meningeal inflammation. FLAIR may even be positive in lymphoma and leukemia, where enhanced scans fail most dramatically. FLAIR
with contrast enhancement increases the yield even higher!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

AKA’s for subarachnoid seeding?

A

meningeal carcinomatosis or carcinomatous meningitis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is a chloroma?

A
Granulocytic sarcoma (chloroma) is a tumor of immature granulocytes found in association with myelogenous leukemias. This soft-tissue mass can occur virtually anywhere and may predate the diagnosis of leukemia. In the CNS, the orbit and epidural
space are affected most commonly, The term chloroma refers to its greenish color akin to chlorophyl. Chloromas portend a blast crisis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Common location for choroid plexus papilloma in adults?

A

4th ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

This tumor compromises 10-20% of intracranial tumors presenting in the first year of life.

A

choroid plexus papilloma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Presentation of choroid plexus papilloma?

A

The tumors present with hydrocephalus and papilledema caused by overproduction of CSF (four to five times normal) or obstructive hydrocephalus caused by tumor, hemorrhage, high-protein CSF, or adhesions obstructing the ventricular outlets.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Apprearance of choroid plexus papilloma?

A

Choroid papillomas are typically hyperdense on unenhanced CT, with a mulberry appearance. Tumors are usually of low signal on T1WI and mixed intensity on
T2WI unless hemorrhage has occurred. These tumors enhance dramatically .

(Calcification occurs in 20% to 25% of cases, and hemorrhage in the tumor is seen even more frequently than calcification.)

37
Q

Contents of an epidermoid?

A

Epidermoids are collections of epithelium with desquamated debris (keratin and cholesterin) resulting from inclusion of ectodermal rests at the time of neural tube closure early in embryonic development.

38
Q

Epidermoids may resemble what other lesion on CT?

A

Sometimes epidermoids are hard to distinguish from arachnoid cysts, particularly
in the cerebellopontine angle cistern. They are low density, similar to CSF.

39
Q

How do you differentiate epidermoids and arachnoid cysts on MR?

A

epidermoids are bright on FLAIR, whereas arachnoid cysts are as
dark as CSF. Otherwise they look the same on T1/2. On DWI these lesions are usually very bright and easily distinguishable from arachnoid cysts, which are dark on DWI.

40
Q

Appearance of dermoid on MR?

A

The high intensity of fat and signal void of calcification on T1WI suggests a diagnosis of a dermoid or teratoma. These lesions more typically occur in the midline as opposed to epidermoids, which are generally off the midline. The possibility of a ruptured dermoid should be considered when multiple fat particles are seen scattered on an MR or when lipid is detected in the CSF.

41
Q

Name the tumor.
A congenital benign hamartomatous lesion derived from notochord remnants, usually located in the retroclival prepontine region, but can be found anywhere from the skull base to the sacrum. Usually asymptomatic. Found in approximately 2% of autopsies.

A

Ecchordosis physaliphora

42
Q

WHO classification of astrocytomas? (1-4)

A

circumscribed astrocytomas (grade I), diffuse astrocytomas (grade II), anaplastic astrocytomas (grade III), and GBM (grade IV) on the basis of histologic criteria

43
Q

most common infratentorial neoplasm in the pediatric age group?

A

Cerebellar juvenile pilocytic astrocytomas (JPAs)

WHO grade I astrocytic tumor

44
Q

Appearance of

A

The typical cerebellar astrocytoma in the pediatric age
group is cystic (60% to 80%), whereas in older patients it is more likely to be solid. A mural nodule may be present with a similar appearance to the hemangioblastomas of adults. The solid portion of the JPA enhances
strongly. In general, pilocytic astrocytomas are well outlined from normal brain, are usually round, and usually are not ominous in appearance.

45
Q

Pleomorphic Xanthoastrocytoma typically occurs where and in whom?

A

<30 years. The lesion shows a preference for the periphery of the temporal lobes as they arise from subpial astrocytes. They may show a base at the meninges in more than 70% of cases.

46
Q

Pleomorphic Xanthoastrocytoma are hard to distinguish

from what other tumor?

A

These tumors are hard to distinguish from dysembryoplastic neuroepithelial tumors. PXAs have a meningeal attachment and no cortical dysplasia, and enhance more frequently.

47
Q

what astrocytoma is associated with tuberous sclerosis?

A

Subependymal Giant Cell Astrocytomas

48
Q

Subependymal Giant Cell Astrocytomas typically occur where?

A

SGCAs typically occur near the foramina of Monro and, in contradistinction with tubers, demonstrate moderate to marked enhancement

49
Q

Besides brain stem glioma, what other lesions may exapnd the brain stem in a child?

A

Other lesions that expand the brain stem in a child include tuberculosis (most common worldwide), lymphoma, rhombic encephalitis (caused by Listeria), and demyelinating disorders (acute disseminated encephalomyelitis and multiple sclerosis).

50
Q

Difference between an anaplastic astrocytoma and GBM on imaging?

A

No necrosis in anaplastic astrocytoma. if
necrosis is seen, bump the lesion up to a GBM. ultimate
dedifferentiation into GBM occurrs in 50% of case of AA>

51
Q

how does relative cerebral blood volume (rCBV) correlates with astrocytoma histology?

A

the higher the rCBV, the more likely one is dealing with a

GBM.

52
Q

When you see a lesion involving the corpus callosum you should put what two lesions near the top of the list of
neoplasms?

A

GBM and lymphoma

53
Q

What condition is associated withmultifocal astrocytomas.?

A

NF-1

54
Q

This tumor commprises 50% of cerebellar

tumors in children, and is the most common paediatric posterior fossa tumour

A

Medulloblastoma (PNET)

55
Q

incidence of calcification and cystic change in medulloblastoma?

A

Medulloblastomas have a 10% to 21% incidence of calcification. Cystic change, initially thought to be rare, occurs in 10% to 20% of pediatric cases and 59% to 82% of adult cases

56
Q

medulloblastomas originate where typically

A

Vermis of cerebellum

57
Q

supratentorial PNETs show calcification how often?

A

50-70%

58
Q

Dysembryoplastic Neuroepithelial Tumor usually has what shape and is found where?

A

Triangular, temporal (50-62%) and frontal (31%) lobes.

On MR, this tumor is characterized by the presence of cysts, usually multiple.

59
Q

“Classic” appearance of an ependymoma in the posterior fossa?

A

A classic appearance of a posterior fossa ependymoma is a calcified fourth ventricular mass that extends through and widens the foramina of Luschka andMagendie.

60
Q

lowest grade ependymoma is found where?

A

filum terminale

61
Q

Difference between ependymoma and subependymoma?

A

Subepenymomas present in late adulthood.

62
Q

the most common mixed glioneural tumors of the CNS? When do they present?

A

Gangliogliomas. Up to 80% before 30 years of age

63
Q

Gangliogliomas occur where most often?

A

Temporal lobes (85%)

64
Q

How do you differentiate a cystic Ganglioglioma from an arachnoid cyst or epidermoid?

A

They are intraparenchymal

65
Q

what do you call a gangliocytoma of the cerebellum? (eponym)

A

Lhermitte-Duclos disease

66
Q

Oligodendroglioma’s are typified by what finding? Who are they found in?

A

high rate of calcification (40-80%)

Men 2:1, 40-50 years

67
Q

gliomatosis cerebri involves how much of the brain?

A

At least 3 lobes

68
Q

The most common primary intraparenchymal tumor in the infratentorial space in adults?

A

Hemangioblastomas

69
Q

Hemangioblastomas occur where most often?

A

More than 83% of HBs occur in the cerebellum

70
Q

clinical symptom attributable to Hemangioblastomas, present 40% of the time?

A

Polycythemia caused by increased erythropoietin production. More common with solid ones.

71
Q

With what condition are Hemangioblastomas commonly associated, and how often?

A

25% of HBs occur in association with von Hippel-Lindau

disease (VHL).

72
Q

Appearance of HB’s on MR & CT?

A

The stereotypical findings of an HB are those of a cystic mass with a solid mural nodule (55% to 60% of cases), which is highly vascular and has serpentine signal voids of feeding vessels. May be solid or rarely cystic. Cytic lesions will have a mural nodule demonstrates striking enhancement. The cyst and its walls do not enhance. A purely solid HB also demonstrates strong enhancement.

73
Q

Best differentials for a hemorrhagic tumor?

A

hemorrhagic metastasis, GBM, oligodendroglioma

74
Q

Signal characteristics of melanoma mets?

A

In the case of melanoma one can identify nonhemorrhagic melanotic metastases as lesions that have high intensity on T1WI and isointensity to hypointensity on T2WI caused by intrinsic paramagnetic effects

75
Q

Breast mets that are estrogen- and progesterone receptor-negative develop mets where?

A

brain and meningeal but not calvarial metastases. Calvarial mets are receptor positive.

76
Q

mets tend to occur where in the brain?

A

Grey/white matter junction (80%)

77
Q

Vasogenic edema and mets?

A

usually out of proportion to the size of the mets

78
Q

what is limbic encephalitis?

A

A paraneoplastic syndrome caused by non-CNS primary tumors resulting in functional and imaging changes in the limbic system. small cell carcinoma of the lung is the classic cause

79
Q

The most common type of lymphoma to affect the brain is ?

A

diffuse histiocytic lymphoma

80
Q

A feature highly suggestive of lymphoma?

A

Coating of the ventricles (seen in 38% of cases) and spread across the corpus callosum are features of lymphoma that are suggestive of, although
not specific for, the diagnosis of lymphoma.

81
Q

an excellent means for distinguishing toxoplasmosis from CNS lymphoma.?

A

thallium scanning

82
Q

Lymphoma is more commonly hyper or hypodense on CT? Does it enhance?

A

Hyperdense, enhances. May be hypodense occasionally in AIDS patients

83
Q

ADC values high or low for lymphoma?

A

Lymphomas are said to have low ADC due to their dense

cellularity restricting water diffusion

84
Q

The most common pineal tumor of the germ cell line is?

A

Germinoma
accounts for 60% of pineal germ cell tumors and 40%
of pineal region masses.

85
Q

Sex distribution for germinoma near the pineal gland? Elsewhere?

A

This tumor, as in all germ cell tumors, has a distinct male predominance when seen in the pineal region (in some series as high as 33:1)

slight female predilection when seen suprasellarly.

86
Q

what’s worse, pineoblastoma or pineocytoma?

A

We say germinomas “engulf” the pineal gland, and pineoblastomas “explode” the gland.

87
Q

In patients with Lhermitte-Duclos disease, what disease is also found 50% of the time?

A

Cowden Syndrome - a multiple hamartoma syndrome.

LD is probably also a hamartomatous tumor of the cerebellum

88
Q

AKA for Lhermitte-Duclos disease?

A

dysplastic gangliocytoma