Distant metastasis of rare malignant struma ovarii (MSO) has been reported for cases associated with papillary thyroid cancer but few with follicular thyroid cancer. A 38-yr-old woman with struma ovarii that was initially diagnosed as “benign” presented with pulmonary metastasis and coughing 17 yr later. The lungs lesions were confirmed to be follicular thyroid cancer by biopsy. Rereview of the initial surgical ovary specimens confirmed the condition to be MSO with follicular thyroid cancer. The patient was treated with total thyroidectomy, which showed no thyroid malignancy, followed by 131I (iodine-131) treatments. Dramatic reduction was observed in both the stimulated thyroglobulin level and the size of the pulmonary metastases over 1 yr. During the following 3-yr follow-up, the patient remained clinically well, with undetectable thyroglobulin (<1 ng/mL) and small stable pulmonary lesions. This is an exceedingly rare case of MSO with follicular thyroid cancer metastasized to the lungs presenting with a late onset but a fortunate excellent response to multidiscipline treatments. It is advisable that struma ovarii be carefully examined to avoid missing malignancy and patients be clinically followed up even with a benign initial diagnosis.
Departments of Nuclear Medicine (H.C., Y.L.)
General Surgery (G.C.)
Pathology (Z.L.), Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing
Department of Oncology, Affiliated Hospital of Qingdao University, Qingdao, China (T.L., J.L.)
H.C. and T.L. contributed equally.
The authors declare no conflict of interest.
Address correspondence and reprint requests to Yansong Lin, MD, PhD, Department of Nuclear Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China. E-mail: email@example.com.