Oral and maxillofacial tumors Benign tumors of the parotid gland Common benign tumors of the parotid gland include pleomorphic adenoma, Warthin tumor, large eosinophilic granuloma, and benign lymphoepithelial lesions. (1) Most 80% of benign parotid tumors are benign mixed tumors. They are pleomorphic adenomas in which there are many histologic components: mucinous gland-like, cartilaginous tissue, fibrous, mucinous, and various other components. These tumors are generally slow growing, but occasionally they grow rapidly and turn malignant, with about 1% to 7% likely to turn malignant (carcinoma, ectrodactyly diverse adenopathy). The facial nerve is most often involved in malignant mixed tumors; however, even in very large benign mixed tumors the facial nerve function is always unimpaired. The clinical presentation of benign mixed tumors is always isolated on the surface of the parotid gland and is well defined with a clear envelope. Occasionally, the tumor is deeper and present in the deep lobes. The most appropriate procedure for this is superficial parotidectomy or subtotal parotidectomy. Tumors deeper in the parotid gland may be more difficult to remove and often always have to be scooped out. However, facial nerve function can still be preserved with careful dissection and separation of the facial nerve and its branches. Poorly done surgery has a high chance of recurrence, especially with enucleation or local excision. It must be kept in mind that all tumors in the parotid region should be seen as parotid tumors unless otherwise proven. All patients should be taken to the operating room for surgery, including standard parotidectomy, identification and dissection of the facial nerve and its branches, and removal of the parotid tumor. Occasionally, a mandibulotomy is indicated for particularly large and deep parotid tumors that have formed a large mass on the lateral pharynx. (2) Worthing tumor, also known as papillary cystic adenoma (lymphomatous). It comes from the lymph nodes around or within the parotid gland and accounts for 10%-15% of all benign periparotid tumors. Ten percent of these tumors are multifocal and 10% are bilateral. This is rarely a malignant lesion and is easily diagnosed with FNA. (3) Large eosinophilic granuloma is a rare, fleshy, slow-growing parotid tumor that accounts for 1% of all parotid tumors. Benign lymphoepithelial lesions have recently become more common due to the increased incidence of AIDS and human HIV-positive rates. They are also common in patients with AIDS-related complex (ARC). These lesions present as a large mass in the caudal part of the parotid gland, which can be cystic in nature. CT can also be used to confirm areas of multiple cysts and bilaterality. The natural history of this disease is unknown and conservative therapy, including multiple needle aspirations and close observation, is commonly used. However, if the patient is symptomatic without HIV infection, surgery may be considered with good outcomes.