This tumor constitutes about 5% of all malignant salivary gland tumors. It is more common in the parotid gland. Usually these tumors are asymptomatic, but may cause pain when they become aggressive. These tumors usually donot involve the facial nerve and commonly is confined to the superfical lobe of parotid gland.
Causative factors of this tumor is not known. Exposure to radiation has always been suspected.
This tumor commonly arises in children and young adults and is rare in elderly. This case is being reported because it is a rarity in this age group. Mucoepidermoid carcinoma may become cystic because of the presence of mucoid cells which secrete mucous. There are two malignant lesions that are known to cause cystic lesions in the parotid gland. They are mucoepidermoid carcinoma and adenocystic carcinoma.
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