Rhinology Tumors and Skull Base Disease Flashcards

1
Q

What type of papilloma arises within the nasal
vestibule and nostril from stratified squamous
epithelium, is more common in males, and can be
treated by simple excision or cauterization?

A

Vestibular (keratotic) papilloma

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

What three types of papillomas arise in the nasal

cavity?

A

● Fungiform papilloma (also called exophytic, septal, or
everted papilloma)
● Inverted papilloma (also called Schneiderian, epithelial,
transitional cell, or Ringertz papilloma)
● Oncocytic papilloma (also called cylindrical)

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

Where do everted papillomas of the nasal cavity

most commonly arise?

A
Nasal septum (rarely: inferior turbinate, nasal vestibule,
nostril)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the gross and microscopic
characteristics of everted papillomas of the nasal
cavity.

A

● Gross: Raised, verrucous, 1 to 15 mm in diameter, single,
unilateral, attached to mucosa via a broad base
● Micro: Branching fronds of mucosa with a connective

tissue core with stratified squamous epithelium; koilocy-
tosis is common

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

What human papillomavirus (HPV) subtypes are
commonly associated with everted nasal
papillomas?

A

HPV 6 and 11.

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

What is the treatment for everted papillomas of

the nasal cavity?

A

Simple excision or cauterization. Rare recurrence or trans-

formation

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

Where do inverted papillomas most commonly
arise within the nasal cavity, and from what
epithelial subtype do they originate?

A

Lateral nasal wall. May also arise from ethmoid air cells or
maxillary sinus. Unilateral > > > bilateral. Schneiderian epi-
thelium.

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

What patient demographic most commonly has

inverted papillomas?

A

White men (0.75F:1M) in their 60 s and 70s

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

Describe the gross and microscopic characteristics

of inverted papilloma.

A

● Gross: Unilateral, pale pink to reddish gray, polypoid
(“mulberry”) mass arising from a stalk (can be broad or
narrow), irregular, friable, often firmer than inflammatory
polyps, although may be difficult to differentiate

● Microscopic: Hyperplastic ribbons of basement mem-
brane and epithelium invaginating into the underlying

stroma. Stroma demonstrates inflammatory changes
containing fibrosis and edema. Multilayered squamous,

columnar, or transitional cell epithelium (or a combina-
tion) containing mucocytes and intraepithelial mucous

cysts

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

Which HPV subtypes are most commonly

associated with inverted papilloma?

A

HPV 16 and 18 although 6 and 11 have been seen as well

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

What is the incidence of malignant degeneration
of inverted papillomas to squamous cell
carcinoma?

A

5 to 10%
Note: Adenocarcinoma and small cell carcinoma have also
been identified.

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

Although the risk of recurrence for inverted
papilloma is high, what might increase the risk of
recurrence?

A

Surgical approach and multicentricity of the tumor

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

What two imaging modalities are used most com-

monly during the workup for inverted papillomas?

A

● Contrast-enhanced CT: Demonstrates bony destruction,
including erosion, remodeling, and sclerosis; may dem-
onstrate areas of calcification within the lesion
● Contrast-enhanced MRI: Can differentiate inspissated
secretions, mucoperiosteal thickening, and inflammatory
changes. T1 lesion is ~ hyperintense to muscle; T2
inspissated secretions and inflammatory polyps are
hyperintense.

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

What are the treatment options available for sino-

nasal inverted papilloma?

A

● Complete surgical excision: Endoscopic or open
● Radiation therapy
● Observation

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

What are the surgical approaches used for endo-scopic and open surgical resection of inverted
papillomas?

A

● Endoscopic: En bloc wide local excision, medial max-
illectomy, Sturman-Canfield operation (Denker opera-
tion), Draf procedure

● Open: Lateral rhinotomy, midfacial degloving, osteo-
plastic flap, frontal sinus trephination

Note: The key is subperiosteal dissection, removal of all
involved mucosa, and drilling down the bone in contact or
attached to the papilloma.

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

When is radiation therapy recommended for

inverted papilloma?

A

● For aggressive, multifocal disease
● For squamous cell carcinoma
● If patient cannot tolerate surgery or if the functional or
cosmetic results of surgical resection are not acceptable
Note: The risks of radiation include potential for malignant
conversion.

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

How long should patients be followed up for
surveillance of inverted papilloma, and when
should CT scans be ordered?

A

Minimum of 5 years. Recurrence most often occurs
between 2 and 10 years. CT scans should be ordered if
scarring limits full visualization of the resection cavity, if the
patient is symptomatic, or there is evidence of recurrence.

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

What is the least common unilateral Schneiderian

nasal papilloma?

A

Oncocytic (cylindrical) papilloma, 3 to 5% of all sinonasal

papillomas

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

You are evaluating the pathology report on a
patient with a lateral nasal papilloma; biopsy was
performed at an outside hospital. The report
describes endophytic invaginations of tall columnar,
multilayered epithelium composed of oncocytes
and containing microcysts laden with mucin and
neutrophils. What is the most likely diagnosis?

A

Oncocytic (cylindrical) papilloma

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

What is the reported malignant potential of
oncocytic papillomas, and what histologic findings
have been reported?

A

10 to 17% (although controversial); squamous cell carci-
noma (most common), mucoepidermoid carcinoma, small
cell carcinoma, and undifferentiated carcinoma

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

Similar to inverted papillomas, oncocytic
papillomas can be locally aggressive and have a
relatively high rate of recurrence. What is the best
management strategy for these tumors?

A

Complete surgical excision, as for inverted papillomas

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

What is the most common benign nasopharyngeal
tumor that most commonly affects prepubescent
males at an average age of 14 to 15 years (range:
10 to 25)?

A

Juvenile nasopharyngeal angiofibroma

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

Describe the major hypotheses put forth to explain the development of juvenile
nasopharyngeal angiofibromas.

A

● Incomplete regression of the first branchial arch artery
● Development from embryologic chondrocartilage of the
skull base at the junction of the palatine bone, horizontal
ala of the vomer, and root of the pterygoid process.
● Abnormality of the pituitary androgen-estrogen axis

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

What is the most common blood supply to

juvenile nasopharyngeal angiofibromas?

A

Internal maxillary artery
Note: May also arise from ascending pharyngeal, external/
internal/carotid artery, and occasionally from contralateral
supply

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

What are the two most common symptoms de-
scribed by patients with juvenile nasopharyngeal
angiofibromas?

A

Epistaxis and unilateral nasal obstruction. More progressive
symptoms can include middle ear effusion, facial deformity,
headache, dacryocystitis, rhinolalia, palatal deformity,
hyposmia/anosmia, cranial neuropathies, and massive
hemorrhage.

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

Describe the characteristic gross appearance of a

juvenile nasopharyngeal angiofibroma.

A

Well-circumscribed, smooth, lobulated, purple to reddish

hue, compressible

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

Describe the characteristic routes of spread or patterns of growth associated with juvenile naso-
pharyngeal angiofibromas.

A

● Pterygopalatine (sphenopalatine) fossa →
● Orbit → middle cranial fossa
● Masticator space → intracranial cavity
● Infratemporal fossa → cheek or intracranial cavity
● Nasal cavity →
● Paranasal sinus (i.e., sphenoid sinus → intracranial cavity)
● Nasopharynx
Note: Dural invasion is rare.

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

CT, MRI, and magnetic resonance angiography
can each be used during the workup of patients
with suspected juvenile nasopharyngeal
angiofibromas. What characteristics are
common?

A

● Epicenter located adjacent to the sphenopalatine fora-
men within the posterior nasal cavity
● Hypervascularity after contrast enhancement
● Distinct pattern of growth
● No regional or distant metastases

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

What specific findings can be seen on CT and
MRI that help distinguish a juvenile
nasopharyngeal angiofibroma?

A

● CT: Bony remodeling without frank bony destruction

● MRI: Flow voids on both T1- and T2-weighted imaging

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

Describe the Holman-Miller sign.

A

Anterior bowing of the posterior maxillary sinus associated with juvenile nasopharyngeal angiofibroma

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

True or False. Because angiography can be used
to identify a source vessel, perform carotid
balloon occlusion studies if necessary, and
perform preoperative embolization in patients
with juvenile nasopharyngeal angiofibromas, it is
considered a required step in the workup and
intervention.

A

False. Angiography, when used 24 to 72 hours preoper-
atively, can provide all of this information and result in

decreased intraoperative bleeding and need for transfusions
and can result in shrinkage of the tumor. However, it is not
required and is considered controversial.

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

What arguments have been made against the
use of preoperative embolization in patients
undergoing resection for a juvenile nasopharyngeal
angiofibroma?

A

● It can potentially obscure the tumor boundaries, resulting
in a higher rate of recurrence
● Complications associated with embolization are not
benign: cerebrovascular accident, blindness, facial para-
lysis, skin or soft tissue necrosis.
● Some argue that tumor hypoxia can decrease the
radiosensitivity of these tumors.

33
Q

What is the most common staging system used

to classify juvenile nasopharyngeal angiofibromas?

A

There is no universal staging system, although several have
been published. The most recent is the Radkowski system
(1996).
● IA: Limited to nasal cavity and nasopharynx
● IB: Involvement of at least one paranasal sinus
● IIA: Minimal extension through the sphenopalatine fora-
men to involve the medial portion of the pterygopalatine
fossa
● IIB: Extensive involvement of the pterygopalatine fossa
with a positive Holman-Miller sign and anterolateral
displacement of the maxillary artery branches. Possible
superior extension with orbital bone erosion
● IIC: Extension through the pterygopalatine fossa to
involve the cheek, infratemporal fossa, or posterior to the
pterygoids
● IIIA: Skull base erosion with minimal intracranial exten-
sion
● IIIB: Skull base erosion with significant intracranial
extension and possible cavernous sinus involvement

34
Q

What treatment options are available for patients

with juvenile nasopharyngeal angiofibromas?

A

● Surgical resection (gold standard; open vs. endoscopic vs.
combined)
● Radiation therapy (30 to 36 Gy, 20 fractions; has been
shown to have similar efficacy to surgery in some
situations)
● Hormonal therapy (controversial and not commonly used)
● Chemotherapy (potentially used for recurrences, rarely
used)

35
Q

What is the risk of recurrence for juvenile
nasopharyngeal angiofibromas, and what increases
this risk?

A

Up to 40%. Large tumors; intracranial extension; involve-
ment of the sphenoid, base of the pterygoids, or clivus; failure to remove all the tumor; or primary radiation
treatment. Most are diagnosed within the first year either
based on symptoms or with MRI.

36
Q

Sinonasal hemangiomas can arise from bone,
mucosa, or submucosa within the nasal cavity and
sinonasal cavities. Both cavernous and capillary
subtypes can be seen. Which is more common in
adults?

A

Cavernous hemangiomas

37
Q

Where do sinonasal hemangiomas most
commonly arise within the nasal cavity and/or
paranasal sinuses?

A

● Cavernous hemangioma → lateral nasal wall or medial
maxillary wall
● Capillary hemangioma → septum

38
Q

What are the most common symptoms

associated with sinonasal hemangiomas?

A

Epistaxis and nasal obstruction. For patients with heman-

giomas restricted to the bone, symptoms may include a firm, painless swelling associated with a pulsatile sensation.

39
Q

Describe the imaging characteristics of sinonasal

hemangiomas on CT and MRI.

A

● CT: Enhance on CT with contrast. It is often indistinct
from turbinates and can be associated with bony
destruction.
● MRI: Enhance with contrast, intermediate signal intensity,
± flow voids. If intraosseous, it may have a soap-bubble,
sun-ray, or honeycomb appearance.

40
Q

What is the management of choice for sinonasal

hemangiomas?

A

Surgical resection. Can consider preoperative embolization,

especially for intraosseous lesions.

41
Q

What pathologic lesion can be seen in the
sinonasal or oral cavity as a rapidly growing mass
resulting in nasal obstruction and epistaxis and is
composed of proliferating capillaries separated
into lobules by loose connective stroma?

A

Lobular capillary hemangiomas (previously known as

pyogenic granulomas)

42
Q

What theories have been presented as
explanations for the formation of lobular capillary
hemangiomas?

A

● Local trauma (e.g., nose picking, nasal packing)
● Hormonal fluctuations (e.g., pregnancy)
● Infection (e.g., influence of viral oncogenes)
● AVM
● Local production of angiogenic growth factors

43
Q

What are the clinical examination findings
associated with a sinonasal lobular capillary
hemangioma?

A

● Purplish/red mass

● Generally < 1 cm, but can be larger

44
Q

What is the treatment of choice for lobular

capillary hemangiomas?

A

Complete surgical excision, although recurrence has been

reported in up to 40%

45
Q
What benign neoplasm can develop from
Zimmerman pericytes (contractile cells
surrounding small vessels) and can be seen in the
sinonasal tract, retroperitoneum, lower
extremities, and pelvis?
A

Hemangiopericytoma

46
Q

What is the typical clinical presentation and gross

appearance of a sinonasal hemangiopericytoma?

A

Nasal obstruction and epistaxis. Gray/tan mass that is
spongy, vascular, and polypoid in appearance and involving
the sinonasal cavity and often one or more paranasal sinus

47
Q

True or False. Sinonasal hemangiopericytomas

can demonstrate malignant potential.

A

True. The risk is low, but regional metastases and death

from disease progression have been reported.

48
Q

What are the typical imaging characteristics

associated with sinonasal hemangiopericytomas?

A

● CT: Homogeneous, enhancing lesions; expansile, result-
ing in bony remodeling

● MRI: Enhance on T2-weighted imaging, intermediate
enhancement on T1-weighted imaging

49
Q

What are the management options available for

sinonasal hemangiopericytomas?

A

Complete surgical resection. Adjuvant radiation and che-
motherapy may play a role, especially in patients with
positive surgical margins. Recurrence rates of up to 19%
have been reported.

50
Q

What is the most common benign tumor of the sinonasal tract that occurs as an expansile prolifer-
ation of mature bone within the membranous

bones of the skull and face?

A

Osteoma

51
Q

Which sinuses are most commonly involved with

osteomas?

A

Frontal > ethmoid > > maxillary > > > sphenoid

52
Q

What is the most likely diagnosis for a patient
with multiple osteomas (often seen in the
mandible), intestinal polyps, and epidermoid
inclusion cysts and desmoids tumors?

A

Gardner syndrome (autosomal dominant)

53
Q

What theories have been described to explain

the development of osteomas?

A

● Embryologic theory (development from the junction of
the frontal bone, which is membranous, and the ethmoid
bone, which is cartilaginous)
● Inflammation/infection theory
● Traumatic theory
● Slow growing osseous hamartomas

54
Q

Describe the three subtypes of osteomas.

A

● Ivory (eburnated): Compact, dense bone, minimal fibrous

tissue
● Mature (spongiosum): Spongy, mature bony, trabeculum
composed of fibrous tissue
● Mixed: Components of both ivory and mature osteomas

55
Q

What is the average growth rate of an osteoma?

A

1.6 mm/year (range: 0.44 to 6.0 mm/year)

56
Q

Although most osteomas are asymptomatic,
they can result in a mass effect such as sinus
outflow obstruction and resultant pain, sinusitis,
and mucocele formation or orbital symptoms,
such as proptosis, diplopia, etc. Less commonly,
osteomas can grow intracranially. In these
situations, what complications can arise?

A

CSF leak, meningitis, pneumocephalus, abscess formation

57
Q

What imaging characteristics are associated with

osteomas?

A

● CT: Range from a high-density lesion to a less dense
ground-glass appearing lesion based on the amount of
mineralized bone
● MRI: Necessary only to evaluate adjacent soft tissue,
trapped secretions, or mucoceles.

58
Q

How are osteomas best managed?

A

● Observation: For lesions that are asymptomatic and
present a low risk for intracranial or orbital complications
● Surgical resection: Endoscopic vs. open vs. combined

59
Q

Name the following disorders associated with
sinonasal exostoses:
● Hyperostosis of the inner table of the skull,
thickened cancellous bone, and intact cortex

sparing the midline and frequently seen in post-
menopausal women
● Hyperostosis in postmenopausal women in the
presence of obesity and hirsutism
● Hyperostosis associated with thickened dura in
adolescent males

A

● Hyperostosis frontalis interna
● Morgagni syndrome (metabolic craniopathy)
● Acromegaly

60
Q

What characteristics can be used to differentiate

an ossifying fibroma from fibrous dysplasia?

A

An ossifying fibroma typically has a capsule and more
mature bone and is more common in black women in their
30s and 40s.

61
Q

What are the imaging characteristics common to

ossifying fibromas?

A

● CT: Well-defined, multiloculated lesion, surrounded by a
bony capsule
● MRI: Hyperintense T2-signal; T1-signal is intermediately
intense centrally and hyperintense peripherally.

62
Q

What is the treatment of choice for ossifying

fibromas?

A

Radical surgical resection (44% recurrence rate)

63
Q

What bony disorder is due to the replacement of normal bone with fibro-osseous tissue (woven-
ossified tissue, increased bony matrix, abnormal

mineralization, marrow fibrosis) that can occur in

monostotic, polyostotic, or syndromic (McCune-
Albright) forms?

A

Fibrous dysplasia

64
Q

Describe the radiographic and histologic

appearance of fibrous dysplasia.

A

● Radiographic pattern: Expansile lesion with relatively
homogeneous smooth ground-glass appearance
● Histologic pattern: Irregularly shaped, patternless woven
trabecular bone within a vascularized fibrous stroma; the
irregular shaped spicules can occur as (1) Chinese writing
type, (2) pagetoid type, and 3) hypercellular type.

65
Q

When should intervention, the gold standard of
which is surgical resection, for fibrous dysplasia
be considered?

A

● Aesthetic concerns

● Compression of neurovasculature resulting in sympto-
matic or functional sequelae
● Functional impairment, such as malocclusion
● To rule out malignancy

66
Q

Although rare (< 4%), malignant transformation
of fibrous dysplasia can occur. What is the most
common cancer associated with this
transformation?

A

Osteosarcoma

67
Q

What is the rate of CSF production?

A

~ 500 mL/day or ~ 20 mL/hour

68
Q

What is the most common cause of anterior

cranial fossa CSF leaks?

A

Noniatrogenic trauma > > iatrogenic trauma > nontraumatic

neoplastic process, spontaneous, congenital

69
Q

What is the most common location for sinonasal

CSF leaks to occur?

A
Ethmoid region (cribriform > lateral lamella) > sphenoid si-
nus (lateral > midline) > > frontal sinus
70
Q

What is the name given to the congenital
dehiscence seen in some patients in the lateral
sphenoid roof and is thought to be due to
persistence of the lateral craniopharyngeal canal?

A

Sternberg canal

71
Q

Describe the reservoir sign.

A

A change in head position, generally leaning forward that
results in a gush of fluid (CSF) collected in an anatomical
depression or open sinus

72
Q

How much CSF is required to test for β-2

transferrin, a protein that is highly specific to CSF?

A

0.4 mL

73
Q

What imaging modality can demonstrate the site
of a CSF leak in the absence of an obvious bony
abnormality based on fine cut CT scanning?

A

CT cisternography (requires intrathecal contrast)
Note: MRI cisternography using highly weighted T2 images
does not require intrathecal contrast but does not
demonstrate the bony anatomy.

74
Q

In a patient with an anterior skull base defect
resulting in CSF rhinorrhea after blunt head
trauma, what is the best first course of action?

A

Conservative management: stool softeners, bed rest,

lumbar drain, and prophylactic antibiotics

75
Q

What are the potential side effects or complications
associated with the use of low-dose intrathecal
fluorescein?

A

In order of frequency (most to least): Malaise, headache,
dizziness, nausea, vomiting, back pain, lower-extremity
weakness, tinnitus, neck pain, fever
At higher doses, seizures and cranial neuropathies have
been reported.

76
Q

What two grafting techniques can be used to

repair skull base defects?

A

Overlay: Graft material is placed over the defect on the
sinonasal side.
Underlay: Graft material is placed over the defect on the
intracranial side.
The two techniques are often used in combination. Grafts
may include mucosa, mucoperiosteum, bone, cartilage,
synthetic material, vascularized local flaps, or free flaps.

77
Q

Which patient demographic is at highest risk for
developing idiopathic intracranial hypertension,
which is thought to be due to chronically
elevated intracranial pressure?

A

Obese women of childbearing age. Recurrent disease is
associated with the number of pregnancies.
Note: This condition was reviously referred to as benign
intracranial hypertension and pseudotumor cerebri.

78
Q

Describe the head and neck symptoms associated

with idiopathic intracranial hypertension.

A

Headache, transient visual obscurations, papilledema,
pulsatile tinnitus; no localizing signs with the exception of
abducens nerve palsy

79
Q

In patients with known idiopathic intracranial
hypertension and a history of recurrent CSF leak,
what additional interventions can decrease the
risk of recurrence?

A

● Weight loss
● Daily acetazolamide
● Ventriculoperitoneal shunt