Metastatic Follicular Variant of Papillary Thyroid Carcinoma Manifested as a Primary Renal Neoplasm

Although autopsies performed on patients with cancer have shown 4 6 to 7.6% of metastases to the kidneys, the preoperative clinical identification remains rare. The primary sources of metastases to the kidney are in decreasing order of frequency: breast, lung, intestine, contralateral kidney, stomach, ovary, cervix, pancreas, uterus, and pro tate. As far as we know, only seven cases of malignant neoplasms of the thyroid gland metastatictothe kidney have been reported [1]. Herein, we report the eighth case of this event and the second of a follicular variant of papillary thyroid carcinoma whose initial manifestation was hematuria and flank pain.