Epithelial-myoepithelial carcinoma of the parotid gland: Case report

Abstract

Introduction and importance

Malignant salivary gland neoplasms present a significant diagnostic challenge, requiring the integration of clinical, radiological, and pathological assessments. Epithelial-myoepithelial carcinoma (EMC) is a rare malignant neoplasm that exhibits a biphasic histopathological pattern. Although the major salivary glands are most commonly affected, EMC can also involve minor salivary glands and, in rare instances, the seromucous glands of the upper aerodigestive tract.

Presentation of case

A 47-year-old male presented with a right-sided parotid mass. On physical examination, a solitary, well-defined, nodular mass, approximately 3 cm in size, was palpated in the right parotid gland, demonstrating mobility. Fine-needle aspiration biopsy indicated a cystic lesion. A right superficial parotidectomy was performed with careful preservation of the facial nerve. The tumor was managed with surgery alone, with negative surgical margins. The patient had no recurrence at the 3-year follow-up.

Clinical discussion

Tumors with features such as positive surgical margins, aneuploidy, nuclear atypia, solid growth pattern, increased mitotic activity, and necrosis are indicative of more aggressive behavior in EMC. Despite being classified as low-grade tumors, EMC has been associated with local recurrence and distant metastasis. In cases exhibiting aggressive characteristics, surgery alone may be insufficient, necessitating the addition of elective neck irradiation to prevent local recurrences. Achieving tumor-negative surgical margins is considered critical for reducing the likelihood of recurrence.

Conclusion

EMC is a rare salivary gland malignancy that requires careful diagnostic evaluation and management. While surgery alone may be sufficient for certain cases with negative surgical margins, further treatment such as irradiation may be warranted in aggressive cases to minimize recurrence.