Background & objectives: Sebaceous carcinoma originating within an ovarian mature cystic teratoma (MCT) is an extremely rare entity. To the best of our knowledge, less than 14 cases have been reported in the literature. Methods: We report a case of a sebaceous carcinoma arising within a mature teratoma. Results: An 83-year-old female presented with urinary retention symptoms. A pelvic MRI scan revealed a left o...