Malignant struma ovarii: A case report and analysis of cases reported in the literature with focus on survival and I¹³¹ therapy

Background. Malignant struma ovarii is a rare type of germ cell tumor that is most often diagnosed postoperatively. The natural history and optimal treatment regimen for the disease are essentially unknown due to the small numbers of published cases. Case. A 32-year-old woman presented with pelvic pain and an ovarian mass that was ultimately treated by total abdominal hysterectomy/bilateral salpingo-oophorectomy. Postoperatively, she was diagnosed with a malignant struma ovarii. The patient was subsequently treated with thyroidectomy and I¹³¹ ablation and is currently disease free. A Medline literature search was performed and clinical data from 23 additional cases were compiled. Conclusion. In this review of 24 cases, 16 patients were followed conservatively postoperatively while 8 received varied additional therapy (4 with I¹³¹). There were 8 recurrences and all occurred in the conservatively managed patients. I¹³¹ for recurrent disease provided an initial complete response in 7 women. Treatment with thyroidectomy and I¹³¹ should be considered in the first line of management for malignant struma ovarii.