A Case of Carcinoma Ex Pleomorphic Adenoma in the Submandibular Region

This report describes a case of carcinoma ex pleomorphic adenoma originating from a recurrent pleomorphicadenoma in a 67-year-old woman. She was referred to our department because of a swelling in the rightcervical region. At presentation, a painless elastic hard tumor measuring 40 X 30mm was located in the right sideof the upper neck.Computed tomography and magnetic resonance imaging showed enhancement of a nodule and a segmentedmass. The biopsy diagnosis was a carcinoma ex pleomorphic adenoma.A radical neck dissection, including the tumor, was performed. Histological examination revealed a rare undifferentiatedcarcinoma. The final diagnosis was a carcinoma ex pleomorphic adenoma because the patient had previouslyundergone a resection of a ipsilateral submandibular pleomorphic adenoma showing atypia and intracapsularinvasion.There has been no sign of recurrence or metastasis for 4 years 8 months postoperatively.