Myoepithelial Cell Carcinoma of the Oral Tongue: Case Report and Review of the Literature.

BACKGROUND

Myoepithelial cell carcinoma is a rare malignant neoplasm of salivary gland origin that typically presents in the parotid gland and minor salivary glands. It has been described previously in head and neck sites such as buccal mucosa, alveolar ridge, and base of tongue.

METHODS

A 55-year-old man presented with 30 years of right-sided tongue pain and 10 years of gradually worsening ulceration. Physical examination demonstrated a 2.5 cm ulcerative lesion of the anterior right oral tongue. An initial biopsy was consistent with moderately to poorly differentiated squamous cell carcinoma. Imaging included a positron emission tomography (PET)/computed tomography (CT) scan that demonstrated the right tongue lesion as well as hypermetabolic right level II adenopathy. The patient underwent surgical excision of the right tongue, upper aerodigestive tract endoscopy, and a bilateral supraomohyoid neck dissection. The tongue defect was closed primarily.

RESULTS

Final pathology of the surgical specimen demonstrated myoepithelial cell carcinoma. All of the margins were free of tumor and no cervical lymph nodes showed metastasis. Immunohistochemistry demonstrated myoepithelial differentiation. The tumor did not show EWSR1 gene rearrangement on genetic testing, suggesting salivary gland origin. Multidisciplinary tumor board evaluation recommended no adjuvant therapy. The patient recovered well after surgery and nearly a year later is without evidence of recurrent or residual disease.

CONCLUSIONS

We present the first reported case of myoepithelial cell carcinoma with primary origin in the oral tongue and review the available literature on this unusual tumor. We discuss the clinical, pathological, and immunohistochemical features and treatment of myoepithelial cell carcinoma.