A Case of Riedel’s Thyroiditis

Riedel’s thyroiditis is a rare disease of unknown etiology, mainly affecting middle-aged to old females. The condition is characterized by an aggressive fibrosis partly or totally replacing the normal thyroid gland tissue. Herein, we report a case of Riedel’s thyroiditis. A 62-year-old woman presented to us with a mass on the left side of the neck and was admitted to the hospital. On palpation, the mass, 40 mm in diameter, was found to be very hard in consistency and not freely mobile. CT revealed a large mass lesion in the left lobe of the thyroid. At operation, the mass was very hard to palpation and adherent to the trachea and esophagus. Histopathological examination revealed fibrous invasion of the connective tissue and organs surrounding the thyroid gland, and based on the findings, we made the diagnosis of Riedel’s thyroiditis. After surgery, the patient has had an uneventful clinical course.