Malignant struma ovarii with a robust response to radioactive iodine

Abstract

Struma ovarii is a rare, usually benign ovarian tumour with malignancy occurring in 3000 μg/L following recombinant TSH administration prior to her first dose of I131. At 25 months following radioiodine treatment, she is in remission with an undetectable thyroglobulin and clear I131 surveillance scans. This case demonstrates an unusual presentation of malignant struma ovarii together with challenges of predicting metastatic disease, and demonstrates a successful radioiodine regimen inducing remission.