Malignant Struma ovarii in a 30-year old nulliparous patient

BACKGROUND: Struma ovarii is a rare monodermal germ cell tumor where the ovary is comprised of at least half thyroid tissue. This phenomenon may indicate an embryological origin. CASE PRESENTATION: A 30-year old nulliparous woman presented with acute right lower quadrant pain and underwent laparoscopic right salpingo-oophorectomy. The excised ovarian mass showed evidence of struma-derived papillary thyroid carcinoma. Ultrasound of the thyroid showed mild enlargement with two solid nodules. A fine needle aspirate of a thyroid nodule was positive for malignancy and a total thyroidectomy was performed. Microscopic features of the thyroid were consistent with papillary thyroid carcinoma. The two tumours were considered as synchronous independent primaries based on their histological presentation. CONCLUSIONS: We believe that aggressive surgical management followed by radioiodine therapy is best to reduce recurrence risk and optimize survival. The broad scope of interventions needed to treat malignant struma ovarii require a strong interdisciplinary team.