Radiation-induced epithelial-myoepithelial carcinoma in a patient previously treated with mantle-field radiation therapy for Hodgkin lymphoma.

Abstract

Radiation-induced salivary gland tumors are well described in the literature, with mucoepidermoid cancer being the most common histologic entity. Epithelial-myoepithelial carcinoma is a rare tumor accounting for <1% of all tumors in the salivary glands. We describe the first case of radiation-induced epithelial-myoepithelial carcinoma in the English-language medical literature. A 48-year-old man presented with right-sided mandibular pain and trismus, 25 years after mantle-field radiation therapy (RT) for Hodgkin lymphoma. He underwent excision of a right submandibular mass, which revealed a diagnosis of epithelial-myoepithelial carcinoma. Although typically a low-grade tumor, the histology revealed extensive necrosis and high mitotic activity. The patient required multiple resections and adjuvant therapy after multiple recurrences over a 4-year period. Reports of epithelial-myoepithelial carcinoma are relatively rare and this case highlights the importance of long-term follow-up and increased awareness of the risks of salivary gland tumors in this population.