Squamous cell carcinoma arising from mature cystic teratoma of the ovary

Mature cystic teratoma (MCT) is the most common germ cell tumor of the ovary. Malignant transformation is found in only 1%–2% of MCTs, with squamous cell carcinoma (SCC) being the most common type, and is extremely difficult to predict early detection for clinicians. We report a case of MCT with malignant transformation to SCC in a 59-year-old postmenopausal female with the initial complaint of pain in the lower abdomen. The case was suspected as MCT based on the magnetic resonance imaging findings and normal range of serum markers. Total abdominal hysterectomy with bilateral salpingo-oophorectomy was done with intraoperative spillage of the tumor occurred. The patient delayed 2 months for the planned adjuvant chemotherapy followed by completion of surgery in view of suboptimal cytoreduction and intraoperative spillage. She developed recurrent disease as bilateral adnexal deposits. She was on chemotherapy with paclitaxel and carboplatin-based combination regimen, and contrast-enhanced computed tomography scan after three cycles of chemotherapy showed decrease in size of metastatic deposits.