Metastatic clear cell renal carcinoma to the thyroid gland: a case report
Introduction: Preoperative diagnosis between primary and secondary thyroid tumors is difficult.
Presentation of Case: A 58-year-old Filipino woman with a history of Renal Cell Carcinoma was admitted for nodular goiter. Biopsy of the nodule was suggestive of papillary thyroid cancer, but final histopathologic results after total thyroidectomy revealed clear cell renal carcinoma metastasis.
Discussion: Head and neck metastasis of renal cell carcinoma is not frequent. Fine Needle Aspiration Biopsy is not enough to diagnose metastatic renal cell carcinoma to the thyroid. A history of clear cell renal carcinoma or multifocal growth pattern and clear cell appearance of cytoplasm by histopathology should be taken into account.
Conclusion: A previous history of renal cell carcinoma should prompt the possibility of metastasis in a patient presenting with thyroid mass even after diagnostic imaging and biopsy.