NKX2-1 and renal cell carcinoma: Thyroid-like follicular carcinoma of the kidney (TLFCK) is an extremely rare subtype of renal cell carcinoma (RCC) that has low malignant potential and exhibits a striking histology that resembles well-differentiated thyroid follicular neoplasms.1 TLFCK, distinguished from kidney thyroidization and metastatic thyroid follicular carcinoma, is characterized as negative for thyroid immunohistochemical markers such as thyroid transcription factor-1 (TTF-1) and thyroglobulin (TG).