Abstract

Introduction: Cancer metastasis to the thyroid from a distant site is rare. A significant proportion of all secondary thyroid tumors are due to metastasis from clear cell renal carcinoma (CCRC). Here, we report a case of thyroid metastasis from a clear renal cell carcinoma several years after the diagnosis.

Case presentation: 71years old male with history of CCRC treated with partial left nephrectomy 9years previously, presented with weight loss and given his history of previous CRCC, further workup with CT thorax, abdomen and pelvis revealed presence of thyroid nodules requiring further assessment. Ultrasound assessment of the thyroid, showed a large, solid and isoechoic right lobe nodule. Fine needle aspiration cytology was non diagnostic on two occasions, total thyroidectomy and histopathological assessment showed evidence of thyroid metastasis from CCRC.

Conclusions: Secondary tumors in the thyroid gland are difficult to diagnose without cytology or histopathologic examination. Therefore, preoperative diagnosis of secondary thyroid neoplasm could be a challenge and requires detailed knowledge of the patient history. History of clear renal cell carcinoma in this case was important and has helped to think about thyroid metastasis before having the tissue diagnosis.

Keywords

metastasis, renal cell carcinoma, thyroid cancer, metastasis, renal, CCRC, TTF-1, metastasis, renal, cell, carcinoma