An 80-seven-year-old woman visited our department for further examination and treatment of a mass in the palate. A mass measuring 32×30 mm was detected in the region from the midline of the palate to the right alveolar part. The results of a biopsy were consistent with a diagnosis of carcinoma ex pleomorphic adenoma. Then, partial maxillectomy was conducted with the patient under general anesthesia. Histologically, the lesion was regarded as carcinoma ex pleomorphic adenoma consisting of the following three tumorous components: pleomorphic adenoma, basal cell adenocarcinoma, and squamous cell carcinoma. The possibility that pleomorphic adenoma has concomitant carcinoma should be considered, and particularly careful examination is necessary in cases that probably have a long past history.
