Endocrine Abstracts

Background: Struma ovarii is a rare form of the ovarian germ cell tumors composed predominantly of mature thyroid tissue. It occurs mostly in the fifth decade. About 5–10% of these tumors are malignant. We present the case of a 20-year-old-woman with papillary thyroid carcinoma arising in struma ovarii.

Case report: A 20-year-old woman presented to her gynecologist with pelvic pain. A right ovarian tumor was discovered at ultrasound examination. The patient was treated by complete right ovariectomy – histopathology revealed papillary thyroid carcinoma arising in struma ovarii (malignant struma ovarii). The patient underwent total thyroidectomy – the thyroid was found to be normal on histology. After operations the patient received ablative radioiodine treatment (200 mCi 131-I). An I-131 posttherapeutic whole-body radioiodine scintigraphy was performed and showed uptake in bone metastases. Thyroid hormone therapy using suppresive doses was introduced after radioiodine ablation. Thyroglobulin level is monitored. Next doses of radioiodine has been scheduled.

Discussion: The treatment of malignant struma ovarii remains controversial. We think that the management of malignant struma ovarii could be the same as in case of thyroid carcinoma, so after surgical removal of ovarian neoplasm, we recommend thyroidectomy, radiotherapy with 131-I and levothyroxine suppressive therapy. Long-term follow-up for the detection of metastases or tumor recurrence by serial serum thyroglobulin measurements and 131-I scan may be required in patients with this rare tumor.