A Rare Cancer of the Tongue That Showed Unusual Histology and Immunohistochemical Phenotype: Case Report

We report a rare case of primary tongue cancer that showed unusual clinical, histological and immunohistological features. The patient was a 73-year-old man who presented with a submucosal tumor in the left side of tongue. Treatment consisted of preoperative chemotherapy, hemiglossectomy, unilateral neck dissection and postoperative chemo-radiotherapy. The tumor locates in the submucosa, independently of the overlying tongue epithelium and the salivary gland. The tumor showed infiltrating growth, arranged in cord or trabecular nests without keratinization or distinct duct formation. The tumor cells were positive for pan-keratin, cytokeratin 7 (CK7) and p63, but negative for other specific markers. Since this tumor did not match any of the defined entity, we diagnosed this lesion as carcinoma, not otherwise specified of the tongue.