Endocrine Abstracts

Introduction: Struma ovarii is an uncommon ovarian neoplasm that more than half of itself is made up of thyroid tissue. In clinical trials about the disease, malign transformation has been detected at the rate of 0.5–5%. Because of the disease’s rareness, there is no absolute agreement about diagnosis and treatment of the disease.

Case report: A 33-year-old woman admitted to gynecology department with abdominal pain. Her pelvic MR revealed 147×99 mm multiseptated cyst in right over which may compatible with teratoma. On laboratory evaluation, her CA-125 level was 43.8 U/ml (normal range: 0–35). The cyst was excised and frozen section analysis was performed. The frozen section showed stuma ovarii so no additional surgical procedure was performed. Diameter of 300 micron papillary thyroid carcinoma was determined at the histopathological examination. At postoperative evaluation, there was no metastasis on thoracic and abdominal imaging. There was no nodule on thyroid USG. In the second operation, omentectomy, excision of paraovarian palpable lymph nodes and right oophorectomy were performed. Pathologic examination revealed no over invasion or lymph node metastasis. Preoperative and postoperative thyroid function tests were measured in normal range; on the other hand postoperative thyroglobulin level was 0.071 ng/ml (normal range: 1.4–78) and anti-thyroglobulin value was 427 IU/ml (normal range: 0–115). Postoperative CA-125 level of the patient was found to be regressed to 12.9 U/ml. Because of the diameter of the tumor tissue, thyroidectomy or adjuvant radioactive iodine therapy treatment was not performed. There has been no recurrence in 1 year follow-up.

Conclusion: There is still no consensus on the diagnosis and treatment of malignant SO. The general approach is that low-risk cases can be followed without adjuvant radioactive iodine therapy such as primary thyroid papillary carcinoma. However, further studies are needed to determine the effect of this approach on recurrence and mortality rates.