Welcome to the ePoster Viewing Panel of AICOG 2025

INTRODUCTION ? ?Struma ovarii? is dominant monodermal growth of thyroid tissue in Ovarian Teratoma. When such ectopic thyroid tissue is found over peritoneum, it is called ?Strumosis? which is considered as malignant spread. AIMS & OBJECTIVES ? To study a rare case of Recurrent Struma Ovarii with Strumosis diagnosed accurately and managed successfully with laparoscopic surgery. To accumulate the current knowledge on Strumosis and learn about Highly Differentiated Follicular Carcinoma of ovarian origin (HDFCO). MATERIALS & METHOD ? A case of a 57 year old P2L2 had a history of Laparoscopic Bilateral Ovarian Cystectomy in 2008 where histopathology suggested Struma Ovarii both ovaries. Currently, after 16 years, when she presented with dull aching abdomen pain and MRI was done, it suggested two solid lesions in the pelvis of 3cm and Ovarian cysts with a raised Thyroglobulin level. She was operated for the same. RESULT ? On Laparoscopy she had a Recto-sigmoid mesentery mass 3cm, a left Iliac fossa peritoneal nodule 1cm and a solid Ovarian 5cm cyst. Laparoscopic Bilateral Salpingo-oophorectomy with excision of these lesions were done. Peritoneal and omental biopsy were taken. Her histopathology report came back as Struma Ovarii with evidence of thyroid tissue in the other two lesions suggesting Strumosis. Her Thyroglobulin levels then done were raised to 450. It was thus considered as a malignant entity and treated with Thyroidectomy followed by Radioactive Iodine. CONCLUSION ? WHO has recently reclassified this emerging clinical entity of Peritoneal Strumosis as an extremely rare subtype - Highly Differentiated Follicular Carcinoma of Ovarian Origin (HDFCO). HDFCO is only diagnosed when signs of spread beyond the ovary are exhibited, proving its malignant behavior. It is often misdiagnosed because of its rarity. It should be treated aggressively as a malignant tumor with radical clearance and Iodine therapy as needed.