these range from various slow - growing benign tumors and low - grade malignancies to fast growing high - grade malignancies .
angiofibromas are one such group of tumors arising in this region , which present as swellings . of these
, nasal angiofibromas ( nas ) are the most common and nas occurring in the region other than the nose are called as extranasopharyngeal angiofibromas ( ena ) .
a 54-year - old male reported to our department with history of swelling over the right side of face since 5 years .
the patient reported insidious onset of swelling with a gradual progress to the present size .
he also reported mild , intermittent , and dull pain in the region of swelling .
clinical examination confirmed a solitary , oval , well - defined swelling measuring approximately 7  5 cm in the preauricular region [ figure 1 ] .
it extended superioinferiorly from the level of outer canthus of the eye to inferior border of mandible and anterioposteriorly extended from 2 cm in front of anterior border of ramus to the mastoid notch [ figure 1 ] .
on palpation , the swelling was firm , non - tender , free from skin , and mobile over the underlying structures .
ultrasonography revealed a large lobulated solid mass of 6  4 cm in the right parotid region with multiple vessels with low velocity flow and without any areas of calcification or cystic changes .
findings were suggestive of a low - grade vascular tumor . computed tomography scan with contrast medium revealed a large well - circumscribed , solitary isodense lesion measuring 6.36  4.39 cm [ figure 2 ] .
it was observed to be extending anteriorly over the superficial lobe of the parotid gland , with anterior displacement of parotid gland .
fnac revealed numerous vascular channels with occasional singly scattered and single cluster of plump spindle cells .
ct- scan transverse section classical superficial parotidectomy was performed under general anesthesia using a modified appiani incision .
tumor mass was dissected anteriorly and excised along with the superficial lobe of parotid gland [ figure 3 ] .
facial nerve was located using the anterograde method and all the branches of facial nerve were preserved .
follow up , facial nerve function was intact and no sign of reoccurrence was observed .
histopathological sections revealed connective tissue with numerous vascular spaces of variable sizes ranging from small capillary - like vessels to partly lined vessels . around the endothelial cells ,
cells were plump or stellate - shaped with mild inflammatory cell response and composed predominantly of plasma cells and a few lymphoid follicles [ figure 4 ] .
photomicrograph shows numerous endothelial lined blood capillaries with collagen fibres interspersed with fibroblasts and fibrocytes ( h&e stain , 40 ) .
( b ) photomicrograph shows endothelial lined blood vessels with connective tissue wall in the background of collagen fibres interspersed with fibroblasts and fibrocytes ( h&e stain , 400 ) photomicrograph of the sections showing the blood vessels positive for cd 34 ( ihc stain , 100 )
various soft tissue tumors , both benign and malignant , present as swelling in the parotid region . clinical examination confirmed a smooth - surfaced , solitary , oval , firm , well - defined swelling measuring approximately 7  5 cm in the preauricular region .
based on the clinical findings of location , consistency and borders a differential diagnosis of pleomorphic adenoma , solitary fibrous tumor ( sft ) , low - grade fibrosarcoma , and lipoma was made . as the most common tumors found in the region are parotid tumors , a provisional diagnosis of mixed parotid tumor was made . however , fnac and contrast - enhanced ct scan were in favor of a tumor with vascular component , shifting the differential diagnosis towards tumors with a vascular component presenting as slow - growing , circumscribed firm swellings .
histopathological examination of the excised lesion revealed features suggestive of angiofibroma and had to be differentiated from lesions with similar features .
the differential diagnosis included low - grade vascular lesions , spindle cell neoplasms , comprising of a large range of benign and low - grade malignant soft tissue lesions , including cellular angiofibroma , sft , low - grade fibromyxoid sarcoma ( lgfms ) , low - grade myxofibrosarcoma , myxoid liposarcoma , giant cell angiofibroma ( gca ) , angiomyolipoma , and angiomyofibroblastoma .
cellular angiofibroma , usually occurs in the pelviperineal region , which would be an unusual location for the tumors reported herein ; however , cases have been reported to have occurred in the buccal mucosa , raising a diagnostic possibility .
cellular angiofibroma shows more rounded , non - branching vessels , often of medium size with thicker walls .
the tumors are generally more uniformly cellular , composed of lesional cells with short , stubby nuclei resembling those of spindle cell lipoma .
sfts occur in a variety of locations in the head and neck region ; myxoid examples may be particularly difficult to identify and should be considered in the differential diagnosis .
microscopically , besides the so - called  patternless  architecture , there is pronounced regional variation in cellularity , prominent thick collagen bundles and characteristic branching ectatic staghorn vessels , which are not accompanied by the abundant smaller - sized vessels present in angiofibroma of soft tissue . in addition , the tumor cells in sft express strong and diffuse cd34 in most cases .
this entity lacks the innumerable , evenly distributed , arborizing thin - walled vessels characteristic of angiofibroma .
lgfms is a distinctive fibroblastic malignant neoplasm characterized by a peculiar tendency to give rise to very late metastases .
histologically , it shows alternating collagenous and myxoid areas with a usually swirling or whorled growth pattern , a frequently lobular appearance , and deceptively bland spindle cell morphology .
the lesions tend to be more hypocellular , with a fibrous component that has uniform collagen deposition rather than the fibrillary or coarsely banded collagen fibers in angiofibroma of soft tissue . although lgfms may contain arcades of thin - walled vessels , vascularity is usually not prominent .
usually occurring in subcutaneous tissues of the extremities , it shows distinctive histologic features including a lobulated growth pattern with infiltrative margins and fusiform , round , or stellate tumor cells with frequently slightly eosinophilic cytoplasm and hyperchromatic atypical or pleomorphic nuclei .
obvious features of malignancy are usually present , characteristic elongated curvilinear vessels with perivascular hypercellularity , these features bear little or no resemblance to the rich vascular network of angiofibroma .
myxoid liposarcoma contains a prominent plexiform network of thin - walled capillaries ( which has been referred to as a  chicken wire  or 
however , it also shows scattered univacuolar and multivacuolar lipoblasts throughout , as well as stromal mucin pools not seen in angiofibroma .
gca has been reported as a benign mesenchymal tumor with 2 cases originating in the buccal mucosa .
although benign , the lesion has potential for local reoccurrence , especially after incomplete resection .
histopathologically , it has similar presentation to that of sft , with presence of multinucleated giant cells not seen in angiofibroma .
angiomyolipoma differs from angiofibromas because of the presence of prominent muscular arteries while angiomyofibroblastoma differs because of the presence of fibrovascular component with a loose myxoid fibroelement .
enas have interstitial stromal tissue predominance with less vascular elements such as that of long - standing na .
other distinctive histologic features are angiofibroma of soft tissue , consisting of a vaguely lobular , variably cellular proliferation of bland , uniform spindle cells set in an abundant , variably myxoid or collagenous extracellular matrix with numerous small , and thin - walled , branching blood vessels .
the complexity of the vascular pattern , often also including larger vessels of varying size and shape , is the most noticeable feature .
immunohistochemical analyses may show that stromal cells have strong cytoplasmic reactivity for vimentin and are generally immunonegative for smooth muscle actin and desmin .
histopathology coupled with immunohistochemistry usually confirms the diagnosis in favor of angiofibroma . in our case ,
the tissue specimen showed features consistent with the diagnosis of ena . in 1980 , de vincentiis and pinelli reviewed a series of 704 cases of angiofibroma and found that 13 cases manifested outside the nasopharynx , thus suggesting that extra nasopharyngeal localization of this tumor is a possible although rare occurrence . a review article by windfuhr and remmert in 2004 summarized 65 patients with enas .
the most common site reported for enas is the maxillary sinus followed by the ethmoid , nasal cavity , and nasal septum .
enas are also reported to originate from the ethmoid sinus , nasal cavity , nasal septum , larynx , sphenoid sinus , cheek , conjunctiva , oropharynx , retromolar area , middle turbinate , inferior turbinate , and tonsil .
other rare sites for enas occurrence have also been described - external nose , hard palate , external ear , lacrimal sac , carotid bifurcation , oesophagus , trachea , facial nerve , middle cranial fossa , and infratemporal fossa .
the most common age of incidence was the second decade ( 46% ) in comparison to 80% of patients with nas .
enas have a higher mean age , i.e , 22 years compared to nas , which have a mean age of 18 years .
this lesion has been described as different from that of the classical nasopharyngeal variety in being more common in females , older individuals with an early presentation , and being capsulated with poor vascularity and infrequent recurrence . unlike nas , enas present non - specific and numerous symptoms .
imaging modalities such as ct scan , mri , ct angiography , and ultrasonography are required for optimal preoperative evaluation of nas and enas .
imaging of nas with a contrast agent leads to diffuse and usually homogenous involvement in ct and mri scans with strong contrast enhancement .
in contrast , enas enhances moderate amount of contrast or none due to its weak vascular involvement . surgical excision is the prime modality of treatment for enas ; radiotherapy maybe applied for non - resectable lesions .
occurrence of enas , although rare in the maxillofacial region , should be considered in differential diagnosis of swellings in this region .
 angiofibromas are rare , benign , locally invasive vascular tumors , which represent 0.05 - 0.5% of all head and neck tumors . 
 most frequent site of occurrence is the posterior nasopharynx , called as nasopharyngeal angiofibromas ( na ) , when these arise outside the nasopharyngeal region they are termed as extranasopharyngeal angiofibromas ( ena ) . 
 only 65 cases of ena have been reported , and the most common site has been reported to be maxilla followed by ethmoids . 
 other unusual sites of occurrence reported so far in literature are nasal cavity , nasal septum , larynx , sphenoid sinus , pterygomaxillary fissure , infratemporal fossa , cheek , oropharynx , retromolar area , middle turbinate , inferior turbinate , and tonsil . 
 ena arising from the superficial lobe of parotid gland has not been reported in the literature so far and this case is the first to be reported . 
INTRODUCTION
CASE REPORT
DISCUSSION