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Indian J Otolaryngol Head Neck Surg
112 (April–June 2009) 61:112–119
123
Abstract
Objectives To fi nd out the geographical distribution, age,
sex, mode of presentation, diagnostic modalities, surgical
approaches, postoperative complications, follow-up and
histopathology of parapharyngeal space tumors (PFT)
through world wide web search (WWWS) and PFT of our
series.
Materials and methods A retrospective study of all PFT
seen and treated in S.R.N Hospital, Allahabad between
1990 and 2006 was done. A systematic review of the litera-
ture was done through WWWS.
Results PFT were commonest in the Asian zone. Inci-
dence was highest in the 3rd and 4th decade. Oropharyngeal
(100%) and cervical (91.6%) swelling were the commonest
presentation. MRI is better than CT scan in evaluating fat
plane. Transcervical approach was the commonest. In our
series, benign tumors (83.4%) were common, constituting
50% of neurogenic and 16.6% of salivary gland origin.
Conclusion PFT were more prevalent in the Asian zone.
Neurogenic tumors were commonest in our study which
contradicts the WWWS of having maximum PFT of sali-
vary gland in origin.
Keywords Parapharyngeal space
Salivary glands
Schwannoma
Imaging
Surgery
Introduction
Parapharyngeal space tumors (PFS) present a diagnostic
challenge. It constitutes less than 0.5% of head and neck
tumors [1].
Previously many such space occupying lesions
were dealt with swelling of the neck and pharynx with
half-hearted attempt in their surgical ablation. Because the
PFS is located deep within the neck, the role of clinical ex-
amination is limited. With popularization of cross-section
imaging by CT and MRI scanning and interpretation of
imaging data based on a combination of these systems, it
is possible to precisely locate a lesion and to even give a
clue to the probable nature of the tumor. In this study an
endeavor was made to fi nd out the epidemiology of PFS
tumors through a WWWS and to see whether there is any
difference in tumors, that we see and the tumors found in
web search.
Materials and methods
The case records of all patients presenting with a diagnosis
of PFT who were treated in ENT, Head and Neck Surgery
Department, SRN Hospital, Allahabad between 1990 and
2006 were reviewed retrospectively. The study included
consideration of geographical distribution, age, sex, clini-
cal presentation, imaging techniques, cytology, surgical
approach, postoperative complications, and follow-up of
cases. Percentages were used for nominal variables and
comparisons. A systematic review of the literature was
done through WWWS. Information about the PFT was
obtained by subject or journal title, title abbreviation, the
NLM ID (NLM’s unique journal identifi er) and by author
names indexed in PubMed and Google search. The database
includes non-paid articles and abstracts in Entrez Pubmed
and Google sites irrespective of the time period.
Main Article
Our experiences with parapharyngeal space tumors and systematic review
of the literature
Mangal Singh
S. C. Gupta
Alok Singla
Indian J Otolaryngol Head Neck Surg
(April–June 2009) 61:112–119
DOI: 10.1007/s12070-009-0047-z
M. Singh ()
S. C. Gupta
A. Singla
Department of ENT and Head & Neck Surgery,
M.L.N. Medical College,
Allahabad, U.P., India
E-mail: drmangalsingh@rediffmail.com
Indian J Otolaryngol Head Neck Surg
(April–June 2009) 61:112–119 113
123
Results
From Jan 1990 to Sept 2006, 12 patients of PFT were
identifi ed in our institution and reviewed. This proves the
rarity of the neoplasm. In WWWS, 580 cases were found
to have PFT. Most of the cases studied were from Asia
(China, Japan and Southeast Asian countries like India,
Indonesia and Thailand). About 318 cases were found
in Asia, 204 cases from North America, 54 cases from
Europe and 4 cases from Africa. So it is most rare in
Africa and South America (Fig. 1). Age varied from 17 to
70 years. The highest incidence was found in the 3rd
and 4th
decade (25% each) in our hospital and in the 3rd
(18.4%)
and 4th (24%) decade in WWWS (Fig. 2). Out of the 12
patients, eight were female. So female preponderance was
observed in our study where as in WWWS male to female
ratio was 1.5:1.
In our cases, the most mode of presentation was oro-
pharyngeal swelling (100%, Fig. 3) causing odynophagia
(58.3%) and diffi culty in breathing (33.3%), cervical
swelling (91.6%, Fig. 4), neurological defi cit (33.3%) like
hoarseness of voice, slurring of speech, weakness of shoul-
der, blurring of vision and multiple cranial nerve palsy. On
detailed analysis of clinical presentation of PFT in WWWS,
we observed oropharyngeal swelling (74.2%) causing ody-
nophagia (70%) and diffi culty in breathing (25%), cervical
swelling (61.2%), neurological symptoms (22.3%) and
multiple cranial nerve (CN) palsy (9, 10 and 11) in 22.3%
cases. Some patients, particularly malignant tumors of
childhood, presented with ear symptom like diminished
hearing, tinnitus and ear discharge.
Investigations
As per records the investigations, which had been done,
were routine blood and urine examinations, imaging stud-
ies like plane X-ray, CT scan and MRI. All patients in our
institution underwent high resolution CT scan. MRI was
done in 5 patients. MRI was found to be better than CT scan
in evaluating fat plane. Figure 5 (A&B) shows MRI of the
patient of pleomorphic adenoma diagnosed by fi ne needle
aspiration cytology (FNAC). In CT scan, the fat plane be-
tween the deep lobe of parotid and tumor was not very clear
whereas in MRI scan it could be seen clearly. It helped in
planning the surgical approach. Hence, this tumor could be
easily removed by transcervical approach through fi nger
dissection. It was found to be minor salivary gland pleomor-
phic adenoma. By studying CT and MRI characteristics and
displacement of vessels in carotid sheath, the probable na-
ture of tumor could be ascertained. Figure 6 (A & B) shows
the CT scan of poststyloid schwannoma with characteristic
non-homogeneous patchy appearance with displacement of
internal carotid artery (ICA) anteriorly. Another CT scan of
rare tumor of fi brohistocytoma shows homogenous mass in
poststyloid area. In WWWS, paragangliomas were found to
have salt and pepper appearance on MRI because of numer-
ous voids within the lesion whereas schwannomas showed
greater enhancement on T2-weighted images, enhanced with
Fig. 1 PFT cases geographical distribution (WWWS) n = 580.
Indian J Otolaryngol Head Neck Surg
114 (April–June 2009) 61:112–119
123
gadolinium and lack of voids. The other modalities of
investigations, which have been done in web search, were
digital subtraction angiography (DSA), carotid angiography
and immunological markers. Twenty-four hour urine analy-
sis for vinyl mandelic acid (VMA) helped in diagnosing
chromaffi n producing paragangliomas. FNAC was found
to be 75% accurate in diagnosing PFT through web search.
In rest of the cases fi nal diagnosis could be ascertained only
after complete excision biopsy.
Surgery
Out of the 12 cases, 8 cases could be removed surgically by
transcervical approach only. One case of deep lobe parotid
tumor was removed by cervicofacial approach. Three out
of the 12 patients required lateral mandibulotomy for com-
plete exposure and extirpation of tumor. One patient who
was initially diagnosed as a case of ectopic pleomorphic
adenoma was found to have lot of adhesions during surgery.
It was diffi cult to remove this tumor even after mandibu-
lotomy. The fi nal diagnosis after complete excision biopsy
was metastatic squamous cell carcinoma. After six months,
primary was detected in the right main bronchus and the
patient died of hemoptysis. In one patient metastatic lymph
nodes in PFS from occult primary after open biopsy were
found. He was subjected to radiotherapy. All benign tumors
could be dissected out easily. However, there was diffi culty
in removing a carotid body tumor and another angiomatoid
Fig. 3 Oropharyngeal swelling in PFT
Fig. 4 Cervical swelling in PFT
Fig. 2 Comparison of age distribution of PFT in WWWS and our study
Indian J Otolaryngol Head Neck Surg
(April–June 2009) 61:112–119 115
123
variant of benign fi brohistocytoma where ligation and exci-
sion of external carotid artery was required for complete
excision. Hypoglossal nerve was retracted during exci-
sion of fi brohistocytoma. In another patient of poststyloid
fi bromyxoma of PFS, the internal carotid artery (ICA) was
engulfed by the tumor itself. This patient required ligation
of ICA and packing of internal juglar vein (IJV) during
extirpation of tumor. However, this patient died after two
weeks due to multiple cranial nerve palsy which lead to sep-
ticemia due to aspiration pneumonia. From this, we learn
that such patients should have undergone balloon occlusion
test combined with brain scan in the preoperative period to
measure the amount of blood fl owing to the brain. If balloon
test is inadequate, such benign tumors may be left as such.
In postoperative period, right vocal cord paresis was found
in one schwannoma patient on second postoperative day,
which improved in six weeks after a course of steroids. One
patient of neurofi broma presented with 9th, 10th and 11th
cranial nerve (CN) paresis, which improved after 8th week
of surgery. In WWWS search, the major surgical approach
was transcervical (82%) followed by transparotid (20%),
preoral (15.75%), combined (11.75%), swing (7.4%), post-
aural (3%) and lateral base skull approach in 2.7% cases.
Mandibulotomy was combined in 20.3% cases. WWWS
showed involvement of cranial nerves (6, 7, 9, 10, 11 and
12) in 19 % cases during postoperative period. The histo-
pathological diagnosis of PFT in present series and WWWS
is illustrated in Table 1.
The period of follow-up in benign tumors varied from
6 months to 10 years except one patient who died in post
operative period due to multiple cranial nerve palsy. There
was no reccurrence in benign tumors. Prognosis remained
singularly poor in malignant tumors. Reccurrence was seen
after 6 months in one patient of metastatic lymph nodes in
PFS from occult primary in bronchus lung. Another patient,
who was subjected to radiotherapy showed regression of
tumor in follow-up. However, he was lost to follow-up after
two months.
Discussion
The parapharyngeal space is an inverted pyramid shaped
potential space which extends from the base of the skull
superiorly to the greater cornua of the hyoid bone inferi-
orly. It is bounded medially by the parapharyngeal wall and
buccopharyngeal fascia, laterally by the medial pterygoid
and ascending ramus of mandible in the anterior portion
and parotid gland with its fascia in the posterior portion.
Because the space is limited above and laterally by the rigid
bones of base of skull and mandible respectively, the natural
expansion of tumors in majority of cases will be medially
towards the pharynx causing smooth bulge in the lateral
pharyngeal wall pushing tonsil anterior-medially. The space
not only contains fascia and muscles which are of little
pathological interest but also the bifurcation of the com-
mon carotid artery, the internal and external carotid arteries,
last four cranial nerves, cervical sympathetic chain and few
lymph nodes. Clinically, the parapharyngeal space should
be considered in two spaces: prestyloid space and poststy-
loid space. Fascia from the styloid process to the tensorveli
palatine muscle divides the parapharyngeal space into these
two compartments. The prestyloid space is anterolateral
and contains cervical portion of the deep lobe of the pa-
rotid gland, minor or ectopic salivary gland, a small branch
of the CN V to the tensor veli palatine muscle, ascending
Fig. 5 MRI showing fat plane in minor salivary gland tumor
Indian J Otolaryngol Head Neck Surg
116 (April–June 2009) 61:112–119
123
pharyngeal artery and pharyngeal venous plexus. The ma-
jority of the prestyloid space is actually fat. The poststyloid
compartment is posteromedial and contains ICA, IJV, CN
IX to XII, cervical sympathetic chain, lymph nodes and
glomus bodies. Lesion may arise from any of this structures
[2, 3].
We have done a WWWS through PubMed and Google
search. Our study included geographical distribution, age,
sex, mode of presentation, diagnostic modalities, surgi-
cal approach, postoperative complications, follow-up and
histopathology. Through web, we found that most of cases
were from Southeast Asian countries such as China, Japan,
Thailand, Singapore and India. Instances of sporadic cases
reports are there but a good series is lacking. “In the series
reported by Work and Gates [4]
and WWWS, the common-
est tumors were benign mixed salivary gland tumors (33.3%
and 41.2% respectively) and neurilimmomas (27.7% and
30.4% respectively). Hughes found that pleomorphic ad-
enoma was the most common neoplasm (40%), followed
by paraganglioma (20%), neurogenic tumor (14%), malig-
nant salivary gland tumor (13%), miscellaneous malignant
tumors (7%), and miscellaneous benign tumors (6%) [5].
However, in our series neurogenic tumors (50%) were most
frequent entities. In one of the most recently published
study on primary parapharyngeal tumors, Luna-Ortiz et al.
from Mexico reported neurogenic tumors to be 57% of all
tumors [6]. We also encountered two rare cases of fi brohis-
tocytoma and fi bromyxoma of PFS.
Neural tumors are derived from neural crest cells. They
can be divided into two main groups: the nerve sheath
tumors and tumors derived from the sympathoblast. The
normal nerve fi ber is ensheathed by schwann cells and
by loosely distributed endoneural fi brolasts. The schwann
cell is the parent cell of both common clinical tumors, the
schwannoma (neurilemmoma) and the neurofi broma [2]. In
the present series, 6 patients had tumors of neurogenic ori-
gin, i.e. two schwannoma of vagus nerve and two neurofi -
broma , one schwannoma of cervical sympathetic chain and
one neurofi broma of hypoglossal nerve. In one case fi bers
of the 10th nerve were found stretched over the capsule of
the tumor from which tumor could be dissected easily. The
patient had postoperatively right vocal cord paresis, which
improved subsequently. In CT scan, schwannoma usually
appeared as non-homogenous patchy mass with displace-
ment of vessels anteriorly (Fig. 6 A&B). In WWWS,
schwannoma constituted about 16.8% of PFT, hence,
the most common type of neurogenic tumor. In WWWS,
shwannomas were heterogeneously hypodense before
contrast enhancement and at least partially hyperdense
after contrast enhancement with displacement of adjacent
vessels at CT, if they were vagal in origin, antero-medially
displacement of ICA. Because most PFS neurogenic tumors
arise primarily from vagal nerve (less commonly arising
from the sympathetic chain or one of the other local nerves)
which is positioned posterior to the ICA, these neurogenic
tumors tend to displace this vessel anteriorly [7].
They may
have a deceptive post contrast enhancement on MRI, appar-
ently due to extravascular accumulation of contrast mate-
rial. The tumor arises from solitary nerve fi ber. Paralysis of
the associated nerve is thus unusual. Malignant change is
also very unusual and may not occur at all [2].
The present study includes three neurofi bromas of PFS.
In other case of neurofi broma, patient had 9th, 10th, 11th
cranial nerve palsy preoperatively which recovered at 8th
week postoperatively. Neurofi broma has an origin from
perineurium and is thus linked inseparably from the nerve
of origin. It usually presents as slowly enlarging painless
neck mass developing over a period of years. Angiography
is needed to differentiate these tumors from paraganglio-
mas, but the fi nal diagnosis must usually wait until excision.
The nerve from which the tumor arises is evident in one in
three operations. It may be stretched over the capsule of the
Table 1 Histopathology of PFT
Histopathology SRN Hospital, Allahabad (in %) World wide web search (in %)
Neurogenic 50.0 33.6
(a) Schwannoma 25.0 16.8
(b) Neurofi broma 16.6. 8.4
(c) Paraganglioma 8.3 8.4
Salivary gland tumors (Pleomorhic
adenoma)
16.6 41.2
(a) Deep lobe parotid 8.3
18.6
(b) Minor salivary gland 8.3 22.6
Miscellaneous (teratomas, giant cell
tumors, lipomas, fi bromatosis)
16.6 (fi brohistocytoma and
fi bromyxoma 8.3 each)
3.2 (rhabdomyomas – 0.7)
Malignant
16.6
21.8
(a) Secondary from occult primary 8.3
(b) Secondary from bronchogenic
carcinoma
8.3
Indian J Otolaryngol Head Neck Surg
(April–June 2009) 61:112–119 117
123
tumor, or the tumor can be in the central core of the nerve
with the fi bers spread around it. All simple tumors should
be excised and an attempt made to rejoin or graft the nerve
[2].
In WWWS, paragangliomas constitutes 8.2% of PFT.
Genetic susceptibility plays a part in the etiology of para-
gangliomas. The gene responsible for transmission of he-
reditary paragangliomas has been mapped to chromosome
11. In large pedigree analysis loci at 11q23 (PGL1) has been
shown to be most commonly associated with mutant PGL
gene which is inherited from carrier father in an autoso-
mal dominant fashion subject to maternal imprinting [8].
Paragangliomas usually were homogeneously hyperdense
after contrast enhancement with incorporation of adjacent
vessels on CT, if they were of carotid origin, lateral dis-
placement of ICA. Presence of internal fl ow voids on MRI
in a mass that is greater than 2 cm is suggestive of paragan-
glioma, rather than schwannoma. Flow voids are not help-
ful in distinguishing between these two lesions when their
mean diameter is less than 2 cm [9]. Oslen et al. described
chronic appearance of paraganglioma, that is, a salt pepper
appearance in all lesions larger than 2 cm in diameter [10].
The paragangliomas arise from chemoreceptor bodies. At
imaging, the three sites of origin may be distinguished.
Glomus vagale and jugulare tumors tend to displace the
ICA anteriorly. Splaying of internal and external carotids
and Lyre’s sign suggests the diagnosis of carotid body
tumor [11]. Glomus vagale tumors have smaller intracra-
nial extensions and better developed capsules than glomus
jugulare tumors. Vagal paragangliomas arise from nests of
paraganglionic tissue within the perineurium of the vagus
nerve at its ganglion nodosum, i.e. just below the skull base.
The carotid body tumor has a much more prominent surface
vasculature than the glomus vagale and can be deeply em-
bedded in the vessel wall, resection extremely painstaking.
Patients present with long history of the slowly enlarging
painless lump in the region of the carotid bulb. About 30%
patients present with parapharyngeal mass [2].
Patients may
present with bruit, blackout and increased carotid sinus
sensitivity. Nerve involvement is rare. The investigation
mandatory is carotid angiogram which demonstrates the tu-
mor circulation, extent of tumor and cross circulation if any.
Investigations of urine catecholamines and metabolites rule
out functional chemodectomas, because the patient may
suffer from hypotensive shock after removal of functional
chemodectomas. Treatment of choice is surgical excision.
Radiotherapy can be given to those who refuse surgery, in
poor risk patients or in metastatic disease. Prognosis is good
[12].
In the present series, two patients had salivary tumors.
These were pleomorphic adenoma originating each from
deep lobe parotid and minor ectopic salivary glands. In one
case tumor arose from minor salivary gland because MRI
scan clearly showed the fat plane between deep lope parotid
and tumor and the tumor was enucleated easily by fi nger
dissection as it was free from parotid gland. The other case
originating from deep lobe parotid which was removed by
cervicofacial transparotid approach. Salivary gland tumors
are the most common primary lesions (40% of all primary
PFS masses) [5, 13] These may cause swelling in one of
3 ways – dumble tumor from the stylomandibular process
of deep lobe of parotid, tumor from the cervical process of
deep lope and minor salivary gland tumor [2, 3]. There is
no consistent physical fi nding that allows a clinician to
differentiate confi dently between a deep lobe parotid mass
and an extraparotid lesion [14]. The best method for mak-
ing this distinction is still the visualization of a fat plane
Fig. 6 CT scan of poststyloid schwannoma of Xth nerve
showing non-homogenous patchy appearance and displacement
of internal carotid artery anteriorly (arrow)
Indian J Otolaryngol Head Neck Surg
118 (April–June 2009) 61:112–119
123
between the deep lobe and the posterolateral aspect of the
mass. This fat plane represents the compressed fi brofatty
supporting matrix of the parapharyngeal space and, when
it is seen; undoubtedly the mass is extraparotid in origin.
When the fat plane is not seen between the mass and the
parotid gland, the lesion is probably a parotid tumor. Thus
an absent fat plane sign correctly identifi ed a tumor as being
intraparotid [15].
In one patient metastatic lymph nodes in PFS from oc-
cult primary after open biopsy was found. He was subjected
to radiotherapy. One patient presented with benign PFT
(pleomorphic adenoma) but after surgical excision, he had
reoccurrence and later was diagnosed as metastatic squa-
mous cell carcinoma from bronchogenic carcinoma of lung.
The patient died of hemoptysis. The enlarged lymph nodes
in carotid space with areas of decreased central accentua-
tion may be either due to neoplastic and infl ammatory cause
[9]. Parotid lesions (mucoepidermoid carcinomas, adenoid
cystic carcinomas and acinar cell carcinoma) are uncom-
mon and mostly arises from the minor pharyngeal submu-
cosal glands. Most malignant tumors of peripheral nerve
arise from the schwannn cell. Neuroblastomas are tumors
of childhood and in the head and neck may be secondaries
from an abdominal tumor or may arise primarily from the
cervical sympathetic chain [2].
The goal of PFT surgery is to provide adequate tumor
visualization to achieve complete tumor removal, while
preserving the surrounding nerves and vessels and control
of any hemorrhage. Overall, transcervical and transparotid
approach are the two main approaches. They have also been
used with mandibulotomy to increase exposure. Transcer-
vical approach is usually used for poststyloid tumors and
transparotid approach for prestyloid tumors. They have also
been used with mandibulotomy to increase exposure. In
the present series, eight cases were removed surgically by
transcervical approach only. One case of deep lobe parotid
tumor was removed by cervicofacial approach. Three out
of 12 patients required lateral mandibulotomy for complete
exposure and extirpation of tumor. One patient who was ini-
tially diagnosed as a case of ectopic pleomorphic adenoma
was found to have lot of adhesion during surgery. It was
diffi cult to enucleate this tumor even after mandibulotomy.
However tumor, was freed from all around and removed in
a single piece. Transcervical approach starts with a trans-
verse incision at the level of the hyoid bone. The subman-
dibular gland is often removed or retracted anteriorly. An
incision through the fascia deep to the submandibular space
allowed for entry into the parapharyngeal space and blunt
dissection of the tumor. Many modifi cations have been
reported. Some surgeons divide the digastric, stylohyoid
and styloglossus muscles from the hyoid bone to improve
exposure. The styloid process and the stylomandibular liga-
ment can also be divided to elevate the mandible anteriorly
to improve access. This approach frequently involves blind
fi nger dissection. Transcervical approach can be combined
with mandibulotomy. Various locations for osteotomy have
been reported, including mandibular body, angle ramus, and
parasymphyseal. The key is to try to limit injury to the in-
ferior alveolar nerve while providing access to the parapha-
ryngeal space. The risk of mandibulotomy includes inferior
alveolar nerve anesthesia, loss of dentition, malocclusion,
mandibular malunion or non-union, and possibly requires
a tracheotomy. Olsen recommended mandibulotomy for
vascular tumors extending into the superior parapharyngeal
space, solid tumors that are confi ned to the superior aspect
of the parapharyngeal space and malignant tumors invad-
ing the skull base [16]. Transparotid approach is commonly
used for deep lobe parotid tumors. It starts with a superfi cial
parotidectomy with facial nerve preservation. The facial
nerve is then separated from the deep lobe of the parotid
gland and retracted. The dissection continued posteriorly
and inferiorly around the mandible.
Many surgeons prefer the transcervical-transparotid ap-
proach. A standard parotidectomy incision is made and car-
ried into the lateral neck. The main trunk and lower division
of the facial nerve are identifi ed. The posterior belly of the
digastric and stylohyoid muscle are divided, allowing for
visualization of the internal and external carotid arteries,
internal jugular vein, CN IX, X, XI, XII, and sympathetic
chain. The styloid process and stylomandibular ligament
may be transected to give a wide opening into the parapha-
ryngeal space. Olsen reported using this technique in 80%
of his case series. He recommended this approach for all
deep lobe parotid tumors, extraparotid salivary tumors and
most of the poststyloid neurogenic tumors [16]. Hughes
also reported that transcervical-transparotid approach to be
the preferred procedure for removal of most parapharyngeal
tumors [5]. For vascular tumors that extend into the superior
portion of the parapharyngeal space, Olsen recommended
cervical-parotid approach with midline mandibulotomy
[16]. Midline lip splitting is used to expose anterior man-
dible. Then the mandible is divided in the midline. An intra-
oral incision is then made in the fl oor of the mouth extend-
ing back to the anterior tonsillar pillar and up to the level of
the hard palate. The hypoglossal nerve and lingual nerve are
preserved. The styloglossus and stylopharyngeus muscles
are divided. The mandible is retracted laterally and supe-
riorly to give wide exposure to the parapharyngeal space.
Tracheotomy is necessary for this approach. Since primary
PFT are increasingly rare, few large scale studies are avail-
able. Shahab recently published his review of PFT for over
27 years of experience, the second largest study in literature
[17]. The 5 and 10-year survival for benign parapharyngeal
tumor is 100%. For malignancies the 5 year survival was
93%, but fall to 57% at 10 years. This study showed that a
patient is highly unlikely to die of a benign parapharyngeal
space tumor, therefore careful consideration of surgical
treatment and discussion with the patient are crucial. While
surgery is the mainstay of the treatment for parapharyngeal
tumor, radiation therapy should be considered in elderly
Indian J Otolaryngol Head Neck Surg
(April–June 2009) 61:112–119 119
123
patients with paragangliomas. Also isolated asymptomatic
parapharyngeal schwannomas in elderly patients with no
nerve defi cit should probably be observed.
Conclusion
Anatomy of PFS is complex with important neurovascular
structures. In the present series, most common age of pre-
sentation was 3th and 4th decade. There was predominance
of females in our study as compared to males in web search.
WWWS has shown highest prevalence of PFT in South
East Asian zone. Oropharyngeal and cervical swelling were
the commonest mode of presentation. FNAC was found to
be diagnostic in 75% of cases in web search. CT scan is
helpful in deciding the site, extent, relationship to styloid
process, parotid gland, vessels and the probable nature of
the neurogenic tumors. MRI was proved to be better than
CT scan in evaluating fat plane in prestyloid compartment.
Benign tumors of neuroectodermal origin were commonest
in our study which contradicts the WWWS of having maxi-
mum PFT of salivary gland in origin. Prognosis remained
favorable for PFT.
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