Squamous cell carcinoma arising in mature cystic teratoma (dermoid cyst) — a rare presentation

Mature cystic teratoma is a common benign adnexal tumour in females. malignant transformation in a mature cystic teratoma of the ovary is rare, occurring in only 1-2% of cases. the most common malignancy is squamous cell carcinoma, which consists of about 75% of malignant transformations. we describe a 43-year-old female with a 14cm right ovarian mature cystic teratoma with the rare finding of squamous cell carcinoma. the clinical evaluation was done with ultrasound, computed tomography (ct) scan and serologic marker serum ca-125. exploratory laparotomy was done to remove the mass. right salpingo-oophorectomy was done. moderately differentiated invasive squamous cell carcinoma arising in the background of mature cystic teratoma (dermoid cyst) was found. further, she had total abdominal hysterectomy, left salpingo-oophorectomy and omentectomy, which were disease-free. she is kept on follow-up with ultrasound, ct scan and serum ca-125. adequately staged patients with disease confined to the ovary have a much better prognosis with 5-year survival rates approaching 95%. purpose of this case report was to create awareness among physicians while dealing with dermoid cysts of large sizes in older patients