Slide 2 Benign Tumors of the Sinonasal Tract SAYED MOSTAFA
HASHEMI MD Slide 3 World Health Organization classification
epithelial tumors (papillomas and salivary glandtype 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 Slide 4 imaging techniques and
the widespread application of endoscopic surgery have led to
revived interest in the management of benign tumors of the
Sinonasal tract Slide 5 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
Slide 6 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 Slide 7 Diagnostic biopsy A
biopsy is required whenever a diagnosis cannot be established by
imaging studies but should be avoided if an angiofibroma is
suspected Slide 8 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 Slide 9 Slide 10 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. Slide 11 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.
Slide 12 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. Slide 13 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. Slide 14 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. Slide 15 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. Slide 16 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.
Slide 17 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 Slide
18 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. Slide 19 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. Slide 20 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. Slide 21 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. Slide 22 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. Slide 23 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, Slide 24 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 Slide 25 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 Slide 26 JUVENILE ANGIOFIBROMA Juvenile
angiofibroma is a benign lesion histologically characterized by
vascular endotheliumlined 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. Slide 27 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. Slide 28 These observations led Schick and colleagues 36 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 Slide 29 Slide 30 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 Slide 31 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 ; Slide 32 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,
Slide 33 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. Slide 34 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. Slide 35 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 Slide 36 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 Slide 37 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 Slide 38 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 radiosurgery 58 and the Cyber knife system 59 might be
alternatives with a low morbidity when used for lesions of limited
size. Slide 39 ckp_intracranial.mp4 ckp_intracranial.mp4 Slide 40
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. .
Slide 41 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. Slide 42 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 Slide 43
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. Slide 44 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. Slide 45 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. Slide 46 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 Slide 47 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). Slide 48 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. Slide 49 surgical management Different
external surgical approachesfrontoethmoidectomy 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 Slide 50 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 Slide 51
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 Slide 52 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. Slide 53 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 Slide 54 etiopathogenesis The
etiopathogenesis of lobular capillary hemangiomas is still obscure.
Trauma, hormonal influences, viral oncogenes, Slide 55 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. Slide 56
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. Slide 57 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 Slide 58 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 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 Slide 59 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
ethmoids81and 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. Slide 60
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 Slide 61 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
Slide 62 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). Slide 63 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. Slide 64 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
