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salivary gland tumors ( sgt ) are uncommon and account for 1% of all head and neck neoplasms .
sgt are more common in adults . minor salivary gland tumors ( msgts ) are unusual , accounting for only 15 - 20% of all sgts . in a study by vaidya et al . , of 104 minor sgt ,
there was no gender predilection and the median age of presentation was 45 years , with a range of 11 - 74 years .
only 0.32 - 5% of all salivary gland tumors occur in children aged less than 16 years . about 90% of pleomorphic adenomas
( pas ) occur in the parotid gland and 10% in the minor salivary glands .
they are responsible for only 5 - 10% of all salivary tumors under 20 years of age .
the most common sites of pas of the minor salivary glands are the palate , followed by the lips and the cheeks .
intraoral pa arising from the mucosa of the cheek is very rare , and most of them have been reported in adults .
we report a case of pa from the buccal mucosa in a 9-year - old female child .
a 9-year - old girl presented to the pediatric outpatient department of the jss hospital , mysore , with a swelling in the right cheek of 4 months duration .
, there was a firm , globular swelling measuring about 2 cm  2 cm in the posterior part of the buccal mucosa opposite the 2 right maxillary molar tooth .
the tumor was removed totally along with a margin of normal tissue with wide excision by the intraoral route under general anesthesia .
macroscopically , it was a grey white globular tissue mass measuring about 2 cm  2 cm [ figure 1 ] .
microscopic analysis showed a tumor with ductal cells arranged in sheets , glandular and acinar pattern in a background of abundant fibromyxoid areas  features consistent with the features of pa [ figure 2 ] .
photograph showing the resected specimen of the pleomorphic adenoma histopathology of the resected specimen showing tumor with ductal cells arranged in sheets , glandular and acinar patterns in a background of abundant fibromyxoid areas
pa is the most common salivary gland tumor accounting for 40 - 70% of all major and minor sgts and occurs mainly in the parotid gland .
they are commonly seen in 4 - 6 decades of life , with a female predominance .
the minor salivary glands are widely dispersed in the upper respiratory tract , including the lip , palate , pharynx , larynx and nasopharynx .
maximum densities of glands are in the palate . in a study by vaidya et al .
intraoral sgt are rare in children and are responsible for only 5 - 10% of all sgts .
the palate is the most common site of msgts , and is followed by the lips and cheek . in a study of pediatric oral lesions from thailand , a large number of lesions belonged to the cystic category ( 35% ) , followed by the inflammatory ( 34% ) and tumor / tumor - like categories ( 25% ) .
pa was seen only in two cases out of the 1251 oral biopsies performed on their patients .
bentz et al . analyzed 324 salivary gland masses in children and observed that 13.3% were sgts and 21% were from the minor salivary glands , with the palate being the most common site .
krolls et al . reviewed 430 cases of salivary gland lesions in children and found 11 pa of the minor salivary glands .
but , site , gender and ages were not mentioned . however , there are only few case reports of pa of the minor salivary glands in children .
jorge et al . reported five cases of pa of the minor salivary glands in children , and all of them were aged between 11 and 18 years .
of the five cases , two were affected on the lips and two on the palate and the tongue was involved in one case . to the best of our knowledge
, only few cases of pa from the buccal mucosa in children have been reported .
the tumors are named pa because of the epithelial and connective tissue components in varying degrees .
pa is histologically characterized by a variety of tissues consisting of epithelial cells arranged in a cord - like cell pattern with a plasmacytoid appearance .
myoepithelial cells are responsible for the production of abundant extracellular matrix with chondroid , collagenous , mucoid and osseous stroma .
both epithelial and mesenchymal elements arise from the same cell clone , which may be myoepithelial or ductal reserve cell . among the intraoral sgts
pa usually presents as a mobile , slow - growing , painless mass ; at times , it may grow rapidly , especially in the palate .
a sudden increase in size may be indicative of infection , hemorrhage or malignant transformation .
however , few cases of ulceration and bleeding have been reported . usually , the size of the pa ranges from 0.8 cm to 5 cm .
most of the lesions are asymptomatic ; therefore , there will be a large interval between the appearance of the lesion and the diagnosis , ranging from a few days to 15 years .
most of the pa from the minor salivary glands in children was noted between the ages of 10 and 18 years .
pa should be considered in the differential diagnosis of mass of the cheek in youngsters .
differential diagnosis of intraoral , solid , asymptomatic swelling include sgt , neurofibroma , rhabdomyosarcoma , lipoma , dermoid cyst , foreign body reaction , mucocele , buccal space abscess , fibroma , adenoid cystic carcinoma and mucoepidermoid carcinoma . in our case , the lack of inflammatory signs , ulceration , pain and invasion ruled out infection and malignancy .
the surgical treatment of pa is complete wide excision with good safety margins to prevent recurrence .
jorge et al . treated all five juvenile pa surgically and , after a long follow - up period , there was no recurrence .
he opined that pa behavior in children is similar to that of adults , with a low recurrence rate after complete surgical resection .
to conclude , this case report alerts the clinicians about the unusual causes of intraoral swellings .
as the swelling is usually asymptomatic , it may be discovered on routine oral examination .
pa of the cheek is rare and should be considered in the differential diagnosis of intraoral swellings of the buccal mucosa .
salivary gland tumors are rare in children and , when they do arise , they mainly affect the major salivary glands . 
 minor salivary gland tumors are rare in children and are responsible for less than 10% of the cases . 
 pleomorphic adenoma is the most common tumor of the salivary glands . 
 the most common sites of pleomorphic adenoma of the minor salivary glands are the palates , followed by the lips and the cheeks . 
 pleomorphic adenoma of the cheek is rare in children and only few cases have been reported so far .