Mature Cystic Teratoma of the Ovary Transforms into Squamous Cell Carcinoma: A Case Report.

Mature cystic teratomas (MCTs) are benign ovarian tumors known to undergo malignant transformation in 1%-2% of cases. Most of these cases lead to squamous cell carcinomas (SCC), and the prognosis is often poor, particularly in advanced-stage disease. A 50-year-old postmenopausal woman presented with a large pelvic mass. The patient initially underwent suboptimal primary surgery and was later diagnosed with stage IIIA SCC arising from MCT. Following the first cycle of chemotherapy with carboplatin and paclitaxel, a computed tomography scan showed a rapidly growing large mass in the pelvic cavity after 4 weeks of primary surgery, leading to a second debulking surgery. However, the patient underwent only one cycle of chemotherapy after secondary debulking surgery because of her poor performance status. Subsequently, after 4 months of secondary debulking surgery, the patient developed rapidly progressive disease, leading to her death approximately after 8 months of diagnosis. While an appropriate multimodal treatment strategy has yet to be established, optimal cytoreductive surgery and adjuvant chemotherapy should be considered for treatment of advanced-stage diseases to improve survival outcomes.