Thyroid metastasis from renal cell carcinoma eight years after radical nephrectomy: a case report.

A forty-five-year-old female patient presented with thyroid nodules eight years after radical nephrectomy for renal cell carcinoma (T2N0M0, grade 2, clear cell subtype) in the right kidney. Ultrasonography of the neck showed multiple hypoechoic macronodules. There was no lymphadenomegaly. During total thyroidectomy following an initial diagnosis of multinodular goiter, frozen section analysis was made, which showed metastasis from renal cell carcinoma. Immunohistochemical studies demonstrated that the tumor cells were negative for thyroglobulin staining. No recurrences or other metastatic disease were seen during a follow-up period of 12 months. Although clinically the thyroid gland is a rare site for tumor metastasis, this possibility should be kept in mind in patients with a previous history of renal cell carcinoma.