Abstract
Myoepithelial carcinoma (MEC) ex pleomorphic adenoma (PA) is defined as a rare malignant myoepithelial neoplasm arising from a primary or recurrent benign pleomorphic adenoma. We report a case of MEC ex PA in the buccal region of a 93-year-old woman. The patient was referred to our hospital because of a mass in her left buccal region. Intraoral examination revealed a protruding mass measuring 25 mm on the left buccal mucosa. MR revealed a well-defined, 47 × 31 × 28 mm lesion in the left buccal area, with inhomogeneous high intensity on T2-weighted images. A biopsy of the tumor suggested a salivary gland tumor, however accurate preoperative diagnosis was difficult. The patient underwent enucleation of the tumor under general anesthesia. The final pathological diagnosis was MEC ex PA. Most of the tumor consisted of MEC, however PA was also observed. Four years and nine months post-operation, the patient has shown no evidence of recurrence or metastasis.
