Abstract
Oncocytic carcinoma is an extremely rare tumor often arising in the salivary gland. In this paper, a case of oncocytic carcinoma of the parotid gland in a 55-year-old man is described. The patient complained of swelling in the left parotid region and underwent superficial lobectomy of the parotid gland. Four months after the operation, the left parotid gland showed a rapid recurrence of swelling. MRI demonstrated a large tumor of the left parotid gland extending to the parapharyngeal space. With a diagnosis of local recurrence of parotid carcinoma, he underwent left total parotidectomy with facial nerve resection and left radical neck dissection. He underwent 50 Gy of postoperative radiotherapy. Histological examination revealed that the tumor consisted of large, granular, and eosinophilic cells with mitosis. Phosphotungstic acid hematoxylin (PTAH) staining showed a presence of numerous mitochondria in the cytoplasm. The diagnosis of oncocytic carcinoma was confirmed based on these findings. The clinical course has been uneventful for 18 months postoperatively.
