Late solitary thyroid carcinoma metastasis to the kidney: a case report

Secondary tumour to the kidney is quite frequent. Even if, theoretically, all solid tumours may give rise to renal metastasis, secondary lesions to the kidney occur more commonly in patients with lung and breast cancer, melanoma and lymphoma. Only 15 cases of renal metastasis arising from a follicular thyroid carcinoma have been reported in the literature. Rarely, metastases to the kidney present as primary renal tumours and may be treated surgically for that mistaken diagnosis. Nevertheless, in patients with solitary late distant metastasis of thyroid cancer, complete surgical resection may be proposed, followed by 131I ablation in order to offer a better chance of prolonged survival. We describe a case of a renal mass undergoing radical surgery and revealing itself as a solitary metastasis from follicular carcinoma of the thyroid, appearing 10 years after total thyroidectomy and 131I ablation therapy.