Epithelial Myoepithelial Carcinoma Masquerading as Simple Parotid Cyst in a Middle Aged Male

Indian J Otolaryngol Head Neck Surg. 2023 Jun;75(2):1186-1189. doi: 10.1007/s12070-022-03388-4. Epub 2023 Jan 9.

Abstract

Epithelial-Myoepithelial Carcinoma (EMC) is a very rarely seen biphasic tumour typically seen in older females and constitutes 0.5-1% of all salivary gland neoplasms. The parotid gland is most often involved and occasionally there may be involvement of submandibular and minor salivary glands. Clinical picture often reveals benign nature of the disease. Computed tomography (CT) and magnetic resonance appearances are non-specific and the cytological diagnosis may be challenging, thus more accurate diagnosis can only be made by histological and immunohistochemical study. There is no consensus regarding the optimal treatment of this neoplasm, largely due to its rarity. Wide surgical excision with a clear margin is the treatment of choice because of the tumour's tendency to infiltrate locally. Adjuvant radiotherapy is often required in cases of large primary tumours and positive surgical margins. The tumour may commonly recur locally after resection in 30-50% of cases. We herein present an unusual case of a 46-year-old male who presented with cystic swelling of left parotid gland and diagnosed as EMC on histopathology and immunohistochemical examination. The patient was treated with surgical resection followed by post-operative radiotherapy.

Keywords: Epithelial-Myoepithelial Carcinoma; Histopathology; Immunohistochemistry; Operating microscope; Parotid gland.