A case of a true malignant mixed tumor of the parotid gland

Abstract

True malignant mixed tumor (carcinosarcoma) of salivary glands, with carcinomatous and sarcomatous components, is aggressive and extremely rare. We report a case of a true malignant mixed tumor in a parotid lesion. A 58-year-old man had a painless right infraauricular mass that had been present for about 30 years. A 6 × 4 cm elastic hard nodule existed from the tragus to the angle of the mandible. The patient underwent total parotidectomy with facial nerve preservation. The entire tumor was resected with the surrounding tissues except along the main trunk of the facial nerve. Histologically, the tumor showed a biphasic pattern composed of both carcinomatous and sarcomatous elements. The carcinomatous component was adenocarcinoma with ductal structure and the sarcomatous components varied from unclassified sarcoma to unequivocal chondrosarcoma. Two months later, the patient suddenly complained of right facial paralysis. Magnetic resonance imaging revealed a irregular mass extending to the parapharyngeal space. A radical operation, combined with chemotherapy and radiotherapy, was performed with neck dissection, partial mandibulectomy and facial nerve sacrifice. Despite these intensive therapies, an X ray study showed multiple pulmonary coin lesions three months after the second operation. We emphasize the necessity for radicality in initial operations when dealing with this type of tumor.