[Thyroid metastasis from clear cell renal carcinoma].

clear cell renal cancer (ccrc) is a tumor with great metastatic potential, but solitary metastases, especially in the thyroid gland, are uncommon and difficult to diagnose1. A patient with a solitary thyroid metastasis from ccrc is reported, and the literature is reviewed. the patient was a 66-year-old male patient with a history of high blood pressure, chronic renal failure, hyperuricemia, current smoking and moderate alcohol consumption, atrial fibrillation, and early cognitive impairment due to Alzheimer’s disease. in 2005 the patient had undergone, at another hospital, left partial nephrectomy for a clear cell tumor. No subsequent adjuvant therapy was given, and abdominal ultrasound and computed tomography (ct) performed in April 2008 showed complete local remission. in October 2008, the patient attended the otolaryngology clinic reporting dysphonia having started one month earlier, with no dysphagia or odinophagia, associated constitutional symptoms, and two cervical tumors also detected in the previous month, a 3-4 cm tumor in the right thyroid lobe (rtL) and a 2-3 cm tumor in the left thyroid lobe (LtL), both hard and adherent to deep planes. Laboratory test results were normal, except for a tSH value of 9 microiU/mL with normal t4 and antithyroid antibodies, and a creatinine level of 1.7 mg/dL. Direct laryngoscopy detected paralysis in the right vocal cord with no other lesions. ct revealed a heterogeneous cervical mass at the expense of the rtL with laryngotracheal d i sp lacement and retrosterna l extens ion, wi th subcentimetric cervical adenopathies and internal jugular vein (iJV) thrombosis (fig. 1). fine needle aspiration (fNA) was not diagnostic due to the lack of cells. Positron emission tomography combined with ct showed thyroid uptake with a low suspicion of malignancy. Based on a preoperative diagnosis of locally advanced thyroid neoplasm with no histological confirmation, total thyroidectomy with lymph node removal from the central and right lateral compartments was decided. Surgery performed in July 2009 found in the rtL a solid, whitish tumor adherent to adjacent tissues, approximately