Thyroid metastasis of bladder transitional cell carcinoma.

The thyroid gland is a rare site for cancer metastasis. We report a 75-year-old man who was referred with a history of hematuria and generalized bone pain for the past few months. He had a past history of partial left lobe thyroidectomy for follicular adenoma. Subsequently he was referred for a thyroid mass and a subtotal thyroidectomy showed a poorly-differentiated carcinoma. On the latest admission, the patient underwent resection of a bladder tumour with malignant histology and an immunohistochemical profile of CK7+/CK20+/34 Beta E12+/CEA-/PSA-. Re-examination of thyroid sections with immunohistochemical stains revealed the malignant cells to be CK7+/CK20+/34 Beta E12+/CEA-/TTF1-. The findings were compatible with metastasis of the bladder transitional cell carcinoma to the thyroid gland.Scans revealed multiple liver and bone metastases. The patient died 2 months after the diagnosis.