Papillary carcinoma of the thyroid in a mature cystic teratoma of the ovary: a case report

Abstract

Mature cystic teratomas (MCT) are composed of a mixture of tissues derived from all three germ layers and are the most common ovarian tumor in both adolescents and women of reproductive age. Although most of these tumors are benign, malignant transformation of MCT occurs only in about 1-2% of cases. Any of the tissues within the MCT, can change malignant transformation. Struma ovarii is a rare ovarian tumor, reported as %0.5-1 of all ovarian masses and <3% of MCT’s. Less than 5% of struma ovarii present malignant transformation. We reported a 66 year-old postmenopausal woman who was admitted for routine control. We revealed solid-cystic mass in the right adnexa that suggested teratoma. We performed total abdominal hysterectomy and bilateral salpingooophorectomy and thyroid papillary carcinoma was determined in pathological assesment. It is difficult to determine the diagnosis prior to surgery, final pathological diagnosis was confirmed as struma ovarii based on the typical morphology of the thyroid follicles and the results of immunohistochemical staining.