Oral Undifferentiated Pleomorphic Sarcoma: A Case Report

Abstract

Undifferentiated pleomorphic sarcoma is a common soft tissue sarcoma in the human body, but it is rarely reported in the oral cavity. This article aims to report a case of UPS in the mandible. An 83-year-old female patient was referred to the Department of Oral and Maxillofacial Pathology at the Faculty of Dentistry in Isfahan, Iran, with a complaint of sudden, painless swelling under her removable complete denture, which had grown gradually over three months. The size of the lesion was approximately 5cm, and there were no radiographic defects present. Neoplastic and malignant proliferation of cells, which is necessary for UPS final diagnosis, was present in the H&E microcopy evaluation. Furthermore, immunohistochemical examination proved that the lesion is an undiffer-entiated pleomorphic sarcoma. Because of the late diagnosis of the disease, the patient died due to lung metastasis before any treatment. © 2025 Tehran University of Medical Sciences.