Shahi et al. Journal of Medical Case Reports 2010, 4:15 http://www.jmedicalcasereports.com/content/4/1/15 C A S E R E P O R T JOURNAL OF MEDICAL CASE REPORTS Open Access Riedel’s thyroiditis masquerading as anaplastic thyroid carcinoma: a case report Navneel Shahi1*, Mohammed F Abdelhamid2, Mudit Jindall3, Reda W Awad2 Abstract Introduction: Riedel’s thyroiditis is a rare thyroid disease characterized by dense fibrous tissues that replace the thyroid gland and invade the adjacent structures that can mimic thyroid malignancy. We discuss the presentation, investigation and management of this very rare condition. Case presentation: We present a case of a 59-year-old African-Caribbean man who presented with a rapidly growing hard neck mass, a hoarse voice, dysphagia and breathing difficulty that clinically suggested thyroid malignancy. Biopsy, however, revealed dense fibrous tissues suggestive of Riedel’s thyroiditis. This was successfully treated with very high dose steroids, with no relapse in the symptoms. Conclusion: It is important for clinicians to be aware of this diagnosis when managing patients with thyroid disease, because Riedel’s thyroiditis can mimic malignancy. In addition, our case demonstrates that this condition should be treated with very high dose steroids to prevent relapse. Introduction Riedel’s thyroiditis is a rare chronic inflammatory dis- ease of the thyroid gland characterized by invasion of the thyroid gland and surrounding structures with dense fibrous tissues. It is a very rare condition. At the Mayo clinic, 37 cases were diagnosed in a series of 57,000 thyroidectomies that were performed between 1920 and 1984. The operative incidence was 0.06% and the overall incidence in outpatients was 1.06 per 100,000 [1]. It is most often seen in women. In a review of 178 patients, 83% were reported to be women. Riedel’s thyroiditis is associated with hypothyroidism, hypoparathyroidism, compression of the trachea, larynx, carotid sheath and esophagus. It may also cause invasion of adjacent muscles and mediastinum. Riedel’s thyroidi- tis is also associated with other fibrous inflammatory processes, including retroperitoneal fibrosis, orbital pseudotumour, mediastinal fibrosis, sclerosing cholangi- tis and fibrosis in other organ systems [2]. We present a rare case of Riedel’s thyroiditis that presented a diagnos- tic dilemma but had a good response to high dose of steroids, with no relapse after a year of treatment. * Correspondence: dr_navi9@yahoo.co.uk 1Warwick Hospital, Lakin house, Lakin Road, CV34 5BW, UK Case presentation A 59-year-old African-Caribbean man presented with a two-month history of neck pain, hoarse voice, dysphagia and breathing difficulties. He had an anterior neck swel- ling that increased rapidly in size. Clinical examination revealed an enlarged, hard and fixed goitre that was very tender on palpation. The trachea was deviated to the left side and there was no cervical lymphadenopathy. Fibre-optic laryngeal examination showed reduced mobility of the right vocal cord. Blood test showed a normal blood cell count and calcium and thyroid func- tion tests, negative thyroid peroxidase autoantibodies and an erythrocyte sedimentation rate (ESR) of 95 mm/ hr. A computed tomographic (CT) scan of the neck and thoracic outlet showed a large enhancing thyroid mass predominantly affecting the right lobe causing deviation of the trachea to the left with no cervical lymphadeno- pathy (Figure 1). During surgery this thyroid mass was found invading all the surrounding structures, including the carotid arteries, internal jugular vein and the right recurrent lar- yngeal nerve. The trachea was significantly deviated to the left side by this mass and no tissue planes could be identified for dissection. Anaplastic carcinoma of the thyroid was suspected, though unlikely due to the age of the patient. As surgical resection was impossible, a © 2010 Shahi et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.