A case of large cell neuroendocrine carcinoma of the tongue

Large cell neuroendocrine carcinomas (LCNEC) are relatively rare tumors that arise in various organs. We report a case of primary LCNEC of the tongue. A 60-year-old man was referred to our department because of impaired swallowing function due to pain while eating, as well as an ulcer on the left side of the tongue. Squamous cell carcinoma was suspected on biopsy. A whole-body examination showed no evidence of metastasis. Therefore, the patient was given a clinical diagnosis of squamous cell carcinoma of the left side of the tongue suspected (cT4aN2bM0: Stage IVa). After preoperative chemotherapy, we performed a tracheostomy, bilateral neck dissection, complete removal of the tongue, and reconstructive surgery using a rectus abdominis free flap, with the patient under general anesthesia. Histologically, the tumor was composed of solid nests of atypical large cells. Necrosis was remarkable. Tumor nests showed peripheral palisading and rosette formation. Immunohistochemically, the cancer cells were positive for chromogranin A and synaptophysin. We diagnosed this tumor as LCNEC, based on the criteria established for pulmonary tumors. The patient is alive without recurrence or metastasis 55 months after surgery. Since LCNEC is exceptionally rare in the head and neck region, especially in the oral cavity, the prognosis was unclear, and treatment has not been established. Hence, studies of further cases are required to establish adequate treatment for LCNEC of the head and neck region.