A case of clear cell carcinoma arising from the base of the tongue

Clear cell carcinoma is a low-grade salivary gland tumor that is indolent and rare. We report a case of clear cell carcinoma arising from the base of the tongue. The patient was a 64-year-old man with a tumor at the base of the tongue incidentally detected during an upper gastroendoscopy. Computed tomography and magnetic resonance imaging revealed a 17-mm tumor arising from the base of the tongue. A biopsy indicated either a clear cell carcinoma arising from a minor salivary gland or metastasis from renal carcinoma; the latter was ruled out by abdominal examination. The tumor was successfully removed by intraoral median glossotomy. After the surgery, fluorescence in situ hybridization analysis revealed that the tumor cells were positive for EWSR1-ATF1 rearrangement, establishing the definitive diagnosis of clear cell carcinoma. No local recurrence or distant metastasis was observed 9 months post-surgery. Esthetics were maintained by the minimally invasive procedure, and the patient’s recovery progressed without any functional impairment such as dysphagia or dysarthria.