Abstract
Ovarian mature teratoma is a benign tumor that predominantly occurs in young women. Malignant transformation is rare, accounting for approximately 1-2% of all cases, and sebaceous carcinoma arising within a mature teratoma is extremely uncommon. We report a rare case of sebaceous carcinoma
arising in an ovarian mature teratoma, together with a review of the relevant literature. The patient was a 73-year-old nulligravid woman. Abdominal contrast-enhanced computed tomography revealed an 18-cm
pelvic mass, and she was referred to our department with a suspected diagnosis of ovarian mature
teratoma. Contrast-enhanced pelvic MRI showed no findings suggestive of malignancy; however, the SCC antigen level was elevated at 3.5 ng/mL. Therefore, intraoperative frozen section diagnosis was planned. A right abdominal salpingo-oophorectomy was performed, and frozen section analysis revealed findings suspicious for squamous cell carcinoma arising in the background of a mature teratoma. Consequently, total abdominal hysterectomy, left salpingo-oophorectomy, and partial omentectomy were added. Final histopathological examination revealed sebaceous differentiation in the area initially suspected to be squamous carcinoma. Based on the presence of frequent mitotic figures, necrosis, and nuclear atypia, the lesion was diagnosed as sebaceous carcinoma arising in an ovarian mature teratoma, classified as FIGO stage IA. No adjuvant therapy was administered, and the patient remains under observation without recurrence. Given the rarity of sebaceous carcinoma and the limited number of reported cases arising within ovarian mature teratomas, this case is presented with a review of the literature.〔Adv Obstet Gynecol, 78 (1), 23-29, 2026(R8.2)〕
