Clear cell carcinoma of the thyroid. A case report.

A rare case of clear cell carcinoma of the thyroid is presented herein. A 31-year-old male had a large soft tumor in the right lobe of the thyroid which showed a hot nodule on scintigram with 99mTc. A right hemithyroidectomy was thus performed after the preoperative diagnosis of a functioning tumor had been made. At surgery, a tiny nodule behind the tumor was found and the histopathological diagnoses of the large tumor and the tiny nodule were clear cell carcinoma and papillary carcinoma, respectively. The thyroglobulin stain was positive in the cytoplasm of many clear cells and scattered colloid. This patient has been well without any evidence of recurrence over the past five years following surgery. The biological characteristics of clear cell carcinoma of the thyroid are discussed in this report.