Epithelial-myoepithelial carcinoma of floor of mouth: A case report with cytological, histological and immunohistochemical correlation.

A 61-year-old female presented with a 3-year-old swelling in the right floor of mouth. Clinical examination and fine needle aspiration cytology suggested a benign lesion. The mass was excised locally along with the involved sublingual and deep part of submandibular gland and duct. Post-operative histopathological examination revealed features of pleomorphic adenoma. However, on revision of histological sections, features were predominantly of a rare malignancy of the salivary glands, epithelial-myoepithelial carcinoma (EMC), along with focal areas of adenoid cystic carcinoma (Ad CC). The tumor was p-63, s-100 and smooth muscle actin positive but C-kit was negative, which ruled out Ad CC and the possibility of a hybrid carcinoma. The aim of this article is to describe a rare case of EMC in the floor of mouth and the confusing cytological picture that it created.