Malignant transformation from mature cystic teratoma of the ovary.

We present a case of malignant change of an ovarian mature cystic teratoma. Our patient was a 48-year-old woman and she visited a primary care doctor presenting with abdominal pain. At her first visit, her pelvic tumor measured 70 × 50 mm by ultrasonography. She was diagnosed as rupture of the malignant tumor occurred secondary to mature cystic teratoma and she took the surgery (abdominal total hysterectomy, bilateral oophorectomy and partial omentectomy). Pathologic diagnosis was squamous cell carcinoma (SCC) occurred secondary to mature cystic teratoma. Treatment with paclitaxel/carboplatin (TC chemotherapy) and gemcitabine hydrochloride/carboplatin (GC chemotherapy) after operation was not effective, and the refractory ileus resulting from rapid progression of the disease continued. She was died of disease progression 7 months after the diagnosis of ovarian cancer. We discuss about the clinical characteristics of malignant transformation of mature cystic teratoma and considered about the treatment of the ovarian SCC.