Tumor-to-Tumor Metastasis: Renal Cell Carcinoma Metastatic to Papillary Carcinoma of Thyroid—Report of a Case and Review of the Literature

摘要

Metastatic disease to thyroid gland is a rare event. Although renal cell carcinoma (RCC) has been reported to metastasize the thyroid gland, metastatic RCC to a thyroid neoplasm is very unusual. We report a case of a 68-year-old man with history of RCC who presented with a 2.5-cm thyroid nodule. Histologic examination demonstrates a renal cell carcinoma metastatic to a papillary carcinoma of the thyroid. The clinicopathologic features of metastatic disease into a thyroid gland neoplasm are shown, and a review of the literature is presented.