An Extremely Rare Case of a Follicular Thyroid Cancer Metastasis to the Ovary: A Case Report

Follicular thyroid cancer (FTC) is a well-differentiated, low-risk cancer of the thyroid gland accounting for approximately 10-15% of all thyroid cancers. The only definitive management of FTC is surgery. Whilst distant metastasis can occur, spread to the ovaries is rare, with only two reported cases. Therefore, we present the third known case of a patient with a primary follicular thyroid cancer that developed ovarian metastases and review the current literature.

A 50-year-old female with a more than 10-year history of a multinodular goitre presented to the Ear, Nose and Throat Surgery, University Hospitals of North Midlands NHS Trust at a tertiary specialist centre with worsening compressive symptoms. A total thyroidectomy was performed and was histologically confirmed as a minimally invasive follicular thyroid cancer. She received radio-iodine ablation therapy. Unexpectedly, uptake was identified in the right ovary on a post-treatment (ablation) nuclear medicine (NM) thyroid I-131 scan and upon further imaging, a cyst was noted within the right ovary.

A bilateral salpingo-oophorectomy and hysterectomy were performed, which revealed a metastatic follicular thyroid carcinoma. Further post-op imaging was unremarkable, and the patient remains disease-free 18 months after her original thyroidectomy.

Appropriate multidisciplinary team (MDT) discussion, as well as detailed imaging and biopsies if indicated, are paramount to obtaining an accurate diagnosis. Surgical resection and radioactive iodine treatment should be considered in appropriate cases in order to control local disease.