Epithelial–Myoepithelial Carcinoma of the Lacrimal Sac and Literature Review of the Lacrimal System

Background Epithelial–myoepithelial carcinomas make up less than 0.1% of head and neck malignancies and are regarded as rare, low-grade malignant neoplasms of the salivary gland. They are thought to arise from intercalated ducts with histopathology showing a classic biphasic morphology of an outer layer of myoepithelial cells and inner layer of epithelial cells. These tumors most commonly occur in the parotid gland; however, rare cases have also been described in the nasal cavity, nasopharynx, subglottis, base of tongue, and the lacrimal gland. Objective To describe the clinical presentation, surgical management, and histopathology of the first reported case of lacrimal sac epithelial–myoepithelial carcinoma. To conduct a literature review of this malignancy, which is present in the lacrimal system. Methods Case report (n = 1) and literature review. Results We report a case of a 72-year-old man presenting with epiphora and a lacrimal sac mass with intranasal extension on imaging and nasal endoscopy. A combined endoscopic endonasal and open approach provided successful definitive treatment for final pathologic diagnosis of epithelial–myoepithelial carcinoma of the lacrimal sac, with orbital reconstruction and lacrimal stenting providing good cosmetic and functional results. Conclusions After PubMed database search for any case series or reports of lacrimal system epithelial–myoepithelial carcinomas, we believe this is the first documented case originating from the lacrimal sac. Although the histopathology of this tumor is distinct, unusual location and clinical presentation may pose significant diagnostic difficulties.