INTRAOSSEOUS ADENOID CYSTIC CARCINOMA OF MAXILLA: AN UNUSUAL PRESENTATION

Abstract

Adenoid cystic carcinoma (ACC) is a relatively rare tumor of epithelial cell origin. Palatal minor salivary glands are the most commonly affected locations followed by parotid, and submandibular glands. Bone lesions are rare. The mandible is more commonly involved than the maxilla. A 36-year-old woman presented with a painless swelling in the right maxilla, resulting in a marked facial asymmetry. Intraorally, a swelling affecting gingiva and crossing the midline of the hard palate was observed. Panoramic radiograph showed an ill-defined radiolucency, involving the right maxilla at the level of alveolar ridge and opacifying the maxillary sinus. Microscopy revealed basophilic cribriform islands and solid sheets of neoplastic cells invading bone trabeculae. Most of the tumoral cells presented myoepithelial characteristics and few true luminal/epithelial. Immunohistochemistry showed positivity for AE1/AE3, CK5, CK7, CK14, CK18, CK19, CK20, p63, α–smooth muscle actin, calponin, CD117, S-100, and Ki-67. ACC in the maxilla are rare but should be considered as differential diagnosis.