Benign Tumors of the
Sinonasal
Tract
SAYED MOSTAFA HASHEMI MD
World Health Organization classification

epithelial tumors (papillomas and salivary gland–type adenomas),

soft tissue tumors (myxoma, leiomyoma, hemangioma,schwannoma,
neurofibroma, and meningioma),

tumors of bone and cartilage (giant cell lesion, giant cell tumor, chondroma,
osteoma, chondroblastoma, chondromyxoid fibroma, osteochondroma,
osteoid osteoma, osteoblastoma, ameloblastoma, and nasal
chondromesenchymal hamartoma).

Juvenile angiofibroma is traditionally included in the group of sinonasal tract
tumors because of its common presentation as a nasal or nasopharyngeal
mass
imaging techniques and the widespread application of endoscopic surgery
have led to revived interest in the management of benign tumors of the Sinonasal
tract
Clinical presentation

Apart from osteomas, which are usually unexpectedly diagnosed on computed
tomography (CT) of the brain or orbits or are associated with frontal
headache in the absence of any other nasal complaint,

The heralding symptom of most benign tumors of the sinonasal tract is
unilateral nasal obstruction,which nowadays requires initial investigation with
endoscopy of the nasal cavities after appropriate decongestion
Imaging studies

common policy to obtain imaging studies, which can help to define the
vascularization of the mass and its relationships with adjacent structures and
to rule out a diagnosis of encephalomeningocele.

In general, our preference is MRI because it can clearly differentiate tumor
from retained secretions, allows higher contrast resolution, and may even
suggest the nature of a soft tissue lesion.

CT with contrast medium enhancement can be considered as a reasonable
alternative
Diagnostic biopsy

A biopsy is required whenever a diagnosis cannot be established by imaging
studies but should be avoided if an angiofibroma is suspected
MANAGMENT

Even though most benign tumors of the sinonasal tract can now be managed
through an endoscopic approach, certain situations still require an external or
a combined procedure.

Need for an external or combined procedure may be clearly suggested by
imaging studies, but there are cases in which a definitive decision can be
made only during surgery.

Consequently, the possibility of switching from an endoscopic to an external
procedure must be discussed with the patient preoperatively
INVERTED PAPILLOMA

Inverted papilloma included in the group of sinonasal papillomas,

it is the second most common benign tumor of the sinonasal tract after osteoma, even though it
represents the most common surgical indication for a benign sinonasal tumor.

Incidence that ranges from 0.6 to 1.5 cases per 100,000 population annually.

Men are more commonly affected than women, and the lesion is typically seen in the fifth and sixth
decades of life.
site of origin

Inverted papilloma most frequently arises from the lateral nasal wall in the
fontanelle area.

The maxillary sinus is the second most commonly affected site, and frontal
and sphenoid sinuses are rarely involved primarily.

Often the lesion extensively involves more than one sinus, making it
impossible to assess the exact site of origin.
Diagnosis

Endoscopy of the nose usually
shows a pale, polypoid lesion with
a papillary appearance that
protrudes from the middle meatus
this can easily suggest the
diagnosis, which is sometimes
made less obvious by the
concomitant presence of
inflammatory polyps.
common symptom

Unilateral nasal obstruction with watery rhinorrhea is the most common
symptom to prompt the patient to seek otolaryngologic consultation

epiphora, proptosis, diplopia,and headache may be associated with an
advanced lesion that involves the orbit or the skull base.
The association of inverted papilloma with
scc

The association of inverted papilloma with squamous cell carcinoma has been
overemphasized, with reported frequencies as high as 56%.

Recent data clearly show that the prevalence varies between 3.4% and 9.7%
and that a synchronous occurrence is more common than a metachronous
one.
The presence of human papillomavirus
(HPV)

Serotypes 16 and 18 have been specifically found to be associated with
inverted papillomas that show histologic signs of malignant transformation.
Imaging studies

Imaging studies are required to assess the extent and three dimensional
configuration of the lesion and to disclose its relationship with surrounding
structures (i.e., orbit, skull base, optic nerve, internal carotid artery)

These goals are best achieved by MRI with gadolinium enhancement,.which
also has the advantage over CT of better differentiating tumor from
inflammatory mucosal changes.
CTS

Numerous studies indicate that focal hyperostosis and osteitic changes seen
on CT may be considered reliable predictors of tumor origin. These findings
may also be identified by MRI
Surgical treatment

Endoscopic surgery is a reliable alternative to traditional external techniques for the vast majority of
lesions.

However, an exclusively endoscopic approach may be contraindicated in the event of

1) massive involvement of the mucosa of the frontal sinus and/or of a supraorbital cell;

2) transorbital extension, a very uncommon situation usually found in patients who have already undergone
one or more surgical procedures;

3) concomitant presence of a malignancy that involves critical areas;

4)presence of significant scarring and anatomic distortion from previous surgery.
key point of endoscopic surgery

To dissect the involved mucosa along the subperiosteal plane and to drill the
underlying bone whenever required by imaging and/or intraoperative
findings.

The extent of the operation is dictated by the site of the lesion and the area
of mucosa involved by the lesion.
Three basic types of endoscopic resections
are

Type I resection is indicated for
inverted papillomas that involve
the middle meatus, ethmoid,
superior meatus, sphenoid sinus, or
a combination of these structures;
even lesions that protrude into the
maxillary sinus without direct
involvement of the mucosa are
amenable to this approach.

Type II resection which
corresponds to an endoscopic
medial maxillectomy, is indicated
for tumors that originate within
the naso ethmoid complex and
secondarily extend into the
maxillary sinus or for primary
maxillary lesions that do not
involve the anterior and lateral
walls of the sinus. The
nasolacrimal duct can be included
in the specimen to increase the
exposure of the anterior part of
the maxillary sinus.
Type III resection so known as the
endonasal Denker operation,

Entails removal of the medial
portion of the anterior wall of the
maxillary sinus to enable access to
all the antrum walls. It is therefore
recommended for the lamina
papyracea.
Frontal sinus involvement
Frontal sinus involvement can be
observed in different scenarios that range
from a limited lesion that grows
marginally from the ethmoid into the
frontal recess to very complex cases in
which most or all of the sinus mucosa is
diseased.
Because the key point for ultimate
success is removal of the lesion along
the subperiosteal plane with the
possibility to drill out the underlying bone,
the surgical choice may involve
a Draf IIB or Draf III endoscopic
sinusotomy or a combination of an
endoscopic approach with external
sinusotomy through an osteoplastic flap,
FLOW UP
The operation should end with the creation of a largely
marsupialized cavity that will give wide access during follow-up
for endoscopic inspection, which should be periodically performed
to diagnose residual or recurrent lesions early.
Postoperatively, MRI or CT is indicated only when a, the patient is symptomatic, or a
residual or recurrent lesion has been histologically documented
outcomes
The most recently published series
clearly show that the recurrence rate is well below
10%.17,26,27
Other than incomplete resection and high-stage disease,
the risk of recurrence was recently found to be associated
with cigarette smoking,28 which also seems to favor
malignant transformation.
29
JUVENILE ANGIOFIBROMA
Juvenile angiofibroma is a benign lesion histologically
characterized by vascular endothelium–lined spaces embedded
in a fibrous stroma that typically affects young male adolescents.
Immunohistochemical and electron microscopy studies
suggest that the lesion could be considered a vascular
malformation (or hamartoma) rather than a tumor.
JUVENILE ANGIOFIBROMA
The lesion has a pathognomonic epicenter of origin at the
level of the pterygopalatine fossa and subsequently grows
through different pathways of spread that typically follow
foramina and fissures of the skull base.
The bone may be involved basically with two mechanisms:
resorption by pressure coming from subperiosteal growth or
invasion of the cancellous component, initially at the level of the
root of the pterygoid process with subsequent expansion within the
greater wing and erosion of the floor of the middle cranial fossa.
These observations led Schick and colleagues36 to postulate that juvenile
angiofibroma might develop from incomplete regression of a
branchial artery, which arises in embryogenesis between days
22 and 24 and forms a temporary connection between the
ventral aorta and dorsal aorta.
This artery commonly regresses and forms a vascular plexus that either
involutes or leaves remnants,which potentially leads to development of
juvenile angiofibroma
Sign & symptom
Unilateral nasal obstruction and epistaxis are the most
common heralding symptoms of small to intermediate-size
juvenile angiofibromas.
In advanced lesions, swelling of the cheek,proptosis, or
headache may be present, which indicates an involvement of
the infratemporal fossa, the orbit, or the cranial fossa,
respectively
The endoscopic finding

The endoscopic finding of
a smooth,
hypervascularized lesion
in a teenage boy that
originates behind the
middle turbinate, which is
usually laterally displaced
against the lateral wall
strongly suggests a
diagnosis of juvenile
angiofibroma;
Diagnosis of juvenile angiofibroma is based on imaging
1) The area of origin invariably located at the level of the pterygopalatine fossa,
2) its hypervascular appearance after contrast enhancement,
3) its pattern of growth.39 On MRI, the presence on both
T1- and T2-weighted sequences of several signal voids within the lesion,
indicating major intralesional vessels,
Differential Diagnosis
Sometimes differentiation of this lesion from lobular
capillary hemangioma, hemangiopericytoma, and
schwannoma can be difficult in view
However, these other lesions do not commonly involve
the pterygopalatine fossa and occur in a different age
group.
Bleeding problem
Although the currently available methods of
embolization provide excellent devascularization of
feeding vessels from the internal maxillary artery and its
branches, as well as from the ascending pharyngeal
artery, control of major vascularization from the internal
carotid artery is challenging
In case of encasement of the internal artery, which is
indeed a very rare event, a balloon occlusion test and
sacrifice of the internal carotid artery or, as a less
invasive procedure, stenting of the intratemporal carotid
artery may be considered.
embolization
Not all authorities concur about routinely performing
preoperative embolization.
In fact, the modifications induced by
this procedure at the tumor periphery have been shown to
increase the likelihood of leaving residual tissue behind.47
management of juvenile angiofibroma
Surgery is considered the mainstay in the management of
juvenile angiofibroma.
Several approaches are currently available
that range from microendoscopic techniques to midfacial
degloving and infratemporal fossa resection
key steps
The key steps to minimizing bleeding and achieving radical resection are the dissection of the
lesion in the subperiosteal plane with the help of bipolar coagulation and an extensive drilling of
the basisphenoid, where the tumor grows with digitations that are difficult to identify even under
magnification.
a dramatic reduction of recurrences with the systematic removal of the cancellous bone of the
sphenoid involved by the lesion
alternatives
The surgeon should also keep in mind that radiotherapy at a low dose (30
to 36 Gy) has been demonstrated to be effective in cases of advanced or
recurrent lesions deemed not amenable to complete resection with
acceptable morbidity.57
The availability of new techniques such as Gamma Knife radiosurgery58
and the Cyber knife system59
might be alternatives with a low morbidity when used for lesions
of limited size.

ckp_intracranial.mp4
Postoperative surveillance

Postoperative surveillance is based on periodic endoscopic and imaging
examination, which should be performed for a minimum of 3 years. Because most of
the residual lesions tend to grow submucosally and residual lesions are diagnosed
within 1 year after surgery., contrast-enhanced CT, or Preferably MRI,plays a key
role in their early detection.

Imaging studies performed in the immediate postoperative period would identify
residual juvenile angiofibroma tissue more easily because of the absence of any
inflammatory changes. most residual lesions are diagnosed within 1 year after
surgery

The actual frequency of residual lesions, although difficult to assess, ranges from
6% to 39%

Treatment in the form of surgery or radiotherapy is scheduled only when there are
clear signs of progressive increase in size.

.
Postoperative surveillance
Because the understanding of the biologic behavior of residual
lesions is still limited, we commonly monitor residual lesions
with MRI to assess their pattern of growth.
Treatment in the form of surgery or radiotherapy is scheduled
only when there are clear signs of progressive increase in size.
Osteoma

Osteoma is a benign, slow-growing osteoblastic lesion and is the most
common benign tumor of the sinonasal tract. It is found in 1% of patients
undergoing plain sinus radiographs and in 3% of those undergoing CT for sinus
symptoms.

Osteomas are generally diagnosed between the second and fifth decades of
life, with a slight male preponderance
Anatomic site
The frontal sinus is the most frequently involved anatomic site (~80% of
cases), followed by the ethmoid, the maxillary sinus, and, more rarely,
the sphenoid sinus.
Osteomas can be observed in conjunction with Gardner syndrome,
a genetic disorder characterized by multiple polyps of the colon
in association with osteomas of the skull and multiple soft tissue
tumors.
main theories have been proposed

1) The embryologic theory proposes that osteoma develops at the junction
between the embryonic cartilaginous ethmoid and the membranous frontal
bone,

2)The traumatic theory correlates the development of osteoma with a
previous trauma;

3) the infective theory is based on the belief that local inflammation may
alter adjacent bone metabolism by activating osteogenesis.

4)slow-growing osseous hamartomas that arise in childhood.
Signs & Symptoms

Most osteomas are asymptomatic and are occasionally diagnosed during
radiographic examinations performed for unrelated reasons.

osteoma may interfere with sinus drainage and can therefore cause sinusitis
or even a mucocele with consequent frontal pain.

If the lesion involves the outer table of the frontal bone, the patient may
complain of aesthetic deformity, whereas tumors that grow toward the orbit
can cause orbital or lacrimal symptoms (i.e., proptosis, diplopia, orbital pain,
epiphora, decreased visual acuity, and even transient blindness).

Osteomas that extend into the anterior cranial fossa carry the risk of
cerebrospinal fluid leak, pneumocele, meningitis, andbrain abscess.
Endoscopic examination
Endoscopic examination of the nasal cavity is usually
normal, because the lesion is deeply located inside a
paranasal cavity.
Only in very rare instances, in which the osteoma grows
toward the nasal cavity, can it be visualized as a firm
mass covered by normal or atrophic mucosa
Imaging assessment
Osteomas is currently based on CT .According to the
amount of mineralized bone within the lesion,
osteomas can exhibit a very high density that
resembles cortical bone or a gradually decreasing
density that displays a ground-glass pattern.
Contrast enhancement is usually unnecessary to
reach a diagnosis
MRI may better delineate the relationship
between
the osteoma and adjacent soft tissues (i.e., dura,
brain, orbital
content).
Managment

Because osteomas are slow-growing lesions, a general consensus in the
literature advocates for a “wait and see” policy for any lesion that is
asymptomatic, does not encroach upon critical structures such as the optic
nerve (risk for intracranial complication), and does not extensively invade the
anterior skull base or the orbit (risk for orbital complication).

it is advisable to monitor the lesion with periodic cross sectional imaging
examinations, which preferably include MRI.
surgical management

Different external surgical approaches—frontoethmoidectomy through a
Lynch-Howarth incision, midfacial degloving, lateralrhinotomy, Caldwell-Luc
procedure, osteoplastic frontal sinusotomy

dramatic change in the surgical management of these lesions, and most are
now treated through a trans nasal approach
surgical management

Cavitation is a surgical trick that helps resect even large osteomas through
the nose; the core of the lesion is drilled with a cutting or diamond bur,
leaving a very thin shell of bone that can be easily fractured and dissected
from the adjacent tissues

The possibility of using a device that induces ultrasound bone emulsification
or performing piezosurgery has also been proposed. Cerebrospinal fluid leak
can be expected during these maneuvers if the lesion is in contact with dura
postoperative surveillance

Because osteoma recurrences are very rare, routine periodic postoperative
surveillance by CT is not justified. We usually perform CT examination 1 year
after surgery and, on the basis of its results, make a decision about further
radiologic follow-up.

The presence of a symptomatic stenotic frontal or maxillary sinusotomy is
another situation that calls for CT examination
LOBULAR CAPILLARY HEMANGIOMA

Lobular capillary hemangioma is a
rapidly growing lesion
characterized by a proliferation of
capillaries arranged in lobules and
separated by a loose connective
tissue stroma, often infiltrated by
inflammatory cells.

The tumor has been commonly
reported in the literature as
“pyogenic granuloma,” which is
currently considered inadequate in
view of the fact that the lesion is
neither the result of a bacterial
infection nor a true granuloma.
lobular capillary hemangioma

FIGURE 48-16. A lobular capillary
hemangioma appears on a coronal
contrast-enhanced magnetic
resonance image as a large
ethmoid lesion that abuts the orbit
and encroaches on the floor of the
anterior cranial fossa. The sharp
borders of the intracranial part of
the lesion and the subtle dural
enhancement suggest extradural
invasion (arrows
etiopathogenesis


The etiopathogenesis of lobular capillary hemangiomas is still obscure.
Trauma, hormonal influences, viral oncogenes,
trauma

The relevance of trauma such as habitual nose picking and nasal packing is
supported by the fact that most lesions are located in the anterior half of the
nasal cavity at the level of the Little area or on the head of the inferior and
middle turbinates.
clinical presentation

In its typical presentation, lobular capillary hemangioma appears at
endoscopy as a red to purple mass, not larger than 1 cm, associated with
epistaxis.75 However, in rarer instances, the lesion reaches a considerable
size and fills the nasal cavity entirely, which leads to a complaint of unilateral
nasal obstruction.
treatment
Surgery is the treatment of choice for lobular capillary hemangioma,
and radical resection can be performed through an endoscopic approach even in
large lesions.3
9
OSSIFYING FIBROMA AND FIBROUS
DYSPLASIA

fibrous dysplasia is a genetically
based developmental anomaly of
the bone-forming mesenchyme with
a defect in osteoblastic
differentiation and maturation that
leads to replacement of normal
bony tissue by fibrous tissue of
variable cellularity and immature
woven bone

Ossifying fibroma is a true benign
neoplasm, main histologic finding
are the absence of a capsule and
the presence of more immature
bone without osteoblastic activity
in fibrous dysplasia
surgical treatment

The objective of surgical treatment is different for the two lesions. Ossifying
fibroma requires radical resection, in view of both the high rate of relapses—
which accounts for 44% of lesions localized in the ethmoids81—and the
aggressive behavior of recurring tumors, with local destruction and potential
invasion of adjacent vital structures.

Successful removal of ossifying fibroma via an endoscopic approach has been
reported in the literature.
surgery For fibrous dysplasia

surgery is intended to relieve symptoms, such as visual impairment as a result
of compression of the optic nerve, or to correct aesthetic deformities.

The type of resection, partial or radical, should be modulated based on the
site of the lesion and consequently on the possibility of ensuing
complications.86

Optic nerve decompression has been traditionally achieved through external
transfacial,neurosurgical, or combined approaches, although most cases can
be managed with endonasal endoscopic surgery
Alternative treatment

Radiotherapy is contraindicated because of the risk of malignant
transformation and the possible side effects on facial skeleton growth in
young patients.

Medical treatment of fibrous dysplasia based on the use of bisphosphonates
(i.e., pamidronate), which inhibit osteoclastic activity, has been used with
success in patients with extensive lesions associated with significant
disfigurement and pain.92,93
SCHWANNOMA

Schwannoma is a neurogenic tumor that arises from the Schwann cells of the
sheath of myelinated nerves.

This is a rare neoplasm that can be found in any part of the body; in 25% to
45% of cases, it is localized at the level of the head and neck. Only 4% of the
lesions involve the sinonasal tract, where the ethmoid, maxillary sinus, nasal
fossa, and sphenoid are involved (listed in order of decreasing frequency).
Sinonasal schwannomas

Sinonasal schwannomas are considered to arise more frequently from the
ophthalmic and maxillary divisions of the trigeminal nerves, but they can also
originate from sympathetic fibers of the carotid plexus or from
parasympathetic fibers of the pterygopalatine ganglion. Particularly in large
lesions, identification of the nerve of origin at surgery is extremely difficult.

At endoscopy, the appearance of
a sinonasal schwannoma is quite
nonspecific; the presence of a
network of capillaries on the
surface can sometimes suggest a
diagnosis of a hyper
vascularlesion