A Case of Primary Squamous Cell Carcinoma of the Thyroid Gland

Primary squamous cell carcinoma of the thyroid gland is an extremely rare case to observe and represents less than 1% in all the primary thyroid malignancies. Normally, squamous epithelium is absent in the thyroid gland and presently; its origin is believed to arise from metaplasia of follicular epithelium. Cancer has very aggressive clinical behavior and a very poor prognosis with survival rates of less than 1 year. The best chances of survival have been achieved with complete resection followed by postoperative radiotherapy. Recently, we came across a case of 80-year-old woman with primary squamous cell cacinoma of the thyroid gland present in the background of Hashimoto's thyroiditis. The patient had swelling in the anterior neck portion from the past 20 days. On physical examinaton, 3× 3c m 2 hard and fixed ill defined mass was detected in the right lobe of thyroid. Repeated fine needle aspiration biopsy of the thyroid revealed the presence of carcinoma. Apparently, Palliative thyroidectomy was performed after 3 months of diagnosis. During operation, the tumor was revealed as a mass of 100 mm in diameter and infiltrated the surrounding muscles, trachea and other soft tissue in the neck. After the operation, the patient's condition deteriorated and ultimately after 5 months of her initial visit, she died due to respiratory failure (J Kor Soc Endocrinol 20:84～89, 2005).