Indian J Surg Oncol (September 2016) 7(3):359–362 DOI 10.1007/s13193-016-0513-5
CASE REPORT
Riedel’s Thyroiditis Mimicking as Anaplastic Thyroid Carcinoma: Unusual Presentation Arsheed Hussain hakeem 1 & Sreerenjini Kaithaparambil Chandramathyamma 2 & Imtiyaz Hussain Hakeem 3 & Fozia Jeelani Wani 4 & Ramesh Gomez 5
Received: 30 September 2015 / Accepted: 16 February 2016 / Published online: 24 February 2016 # Indian Association of Surgical Oncology 2016
Abstract Riedel’s thyroiditis is a rare inflammatory process which not only involves thyroid gland but also the surrounding vital structures. It may also be associated with various forms of systemic fibrotic disorders. The exact etiology is not known, but currently most favored view is that of a localized form of systemic fibrotic process. We report a case of Riedel’s thyroiditis in a patient, highlighting a rare presentation mimicking anaplastic carcinoma. Clinical awareness of such presentation of Riedel’s thyroiditis would enhance our ability to make this diagnosis promptly. Apart from avoiding or minimizing aggressive surgical intervention, awareness of
such clinical entity may avoid complications and hence morbidity. Our case also highlights the difficulty in histological diagnosis which is very important to rule out malignancy and avoiding any major surgical intervention fraught with complications. Good response to high dose steroids as seen in our case is the current accepted treatment of choice. Keywords Riedel’s thyroiditis . Thyroid mass . Anaplastic carcinoma
Background Institution where work was done: Apollo cancer Hospital, Hyderabad, India. * Arsheed Hussain hakeem [email protected] Imtiyaz Hussain Hakeem [email protected] Fozia Jeelani Wani [email protected] Ramesh Gomez [email protected]
1
Department of Head and Neck Oncology, Apollo Cancer Hospitals, Hyderabad 500096, India
2
Department of Histopathology, Lakeshore Hospital and Research Center, Maradu Kochi, Kerala, India
3
Department of Internal Medicine, Poplar Bluff Regional Medical Center, MO, USA
4
Department of Gynaecology and Obstetrics, Apollo Hospitals, Hyderabad 500096, India
5
Department of Endocrinology, Lakeshore Hospital and Research Center, Maradu Kochi, Kerala, India
Riedel thyroiditis is a rare fibrotic condition affecting thyroid gland, characterized by replacement of the thyroid parenchyma with fibrosis [1]. This fibrotic process may not be limited to the thyroid only, but invades the surrounding vital structures [2, 4]. The exact etiology of the condition is not known but the current view favors it to be a local manifestation of a systemic fibrotic process or an autoimmune process [3, 4]. The common presentation of the Riedel’s thyroiditis is firm mass of the thyroid with associated symptoms like hoarseness, dyspnea, dysphagia and aphonia, usually caused by local infiltration of the advancing fibrotic process [5]. Infiltration of the surrounding vital structures may cause hypoparathyroidism, compression of the trachea, larynx, carotid sheath and esophagus. It may also cause invasion of strap muscles and fibrotic process may extend to superior mediastinum. We present a rare case of Riedel’s thyroiditis that presented as a diagnostic problem and clinically mimicked anaplastic carcinoma as whole thyroid gland was enlarged and rock hard on palpation and immobile due to infiltration into the surrounding structures. Clinical awareness of such a unique and rare presentation of Riedel’s thyroiditis should help us to make this diagnosis promptly. It will not only help in diagnosis but also alert the clinician to
360
Indian J Surg Oncol (September 2016) 7(3):359–362
minimize overly aggressive surgical intervention, thus avoiding complications and morbidity. Our case also highlights the good response to the steroids which may greatly enhance the clinical outcome.
Case Presentation A 50 year-old female, known case of hypothyroidism was referred to our head and neck clinic for long standing swelling lower neck with rapid increase in size from past 4 months. The main symptom associated was feeling of strangulation of the neck. It was not associated with dysphagia or hoarseness. There were no definite symptoms of inflammation like pain, edema, fever, malaise, or myalgias. She had undergone total hysterectomy for benign uterine ailment 10 years ago. On palpation of the neck there was a large swelling in the lower midline neck moving with deglutition. It was hard in consistency, most likely arising from the thyroid gland and involved both lobes of the thyroid gland and isthmus. Although the upper margin was distinct, the lower margin was not felt as the mass extended below clavicles on the both sides. There were no palpable lymph nodes in the neck or any other part of the body. Thyroid function test showed hypothyroidism: T3 of 52.3 ng/ dL (71 to 161 ng/dL), free T4 of 0.3 ng/dL (0.8 to 1.7 ng/dL), thyroid stimulating hormone (TSH) of 55 IU/mL (0.86 to 4.69 μIU/mL). Magnetic resonance imaging showed a diffusely enlarged mass involving both thyroid lobes and isthmus, extending to the infra- hyoid level and encircling the trachea and thyroid cartilage (Fig. 1). Magnetic resonance imaging also demonstrated that thyroid mass was homogeneously hypointense on both T1- and T2-weighted images (Figs. 1 and 2). There was no evidence of tracheal invasion on MRI. FNAC and Tru cut biopsy showed only plasma-lymphocytic infiltrates and malignant neoplasm such as anaplastic carcinoma could not be ruled out. The clinical features were favouring anaplastic transformation of longstanding thyroid nodular disease. Open
Fig. 1 Axial T1 weighted magnetic resonance imaging demonstrating homogeneously hypo-intense mass involving whole of thyroid gland and encasing the trachea
Fig. 2 Axial T2 weighted magnetic resonance imaging demonstrating homogeneously hypo-intense mass involving whole of thyroid gland and encasing the trachea
thyroid biopsy was performed to diagnose and also to rule out other malignant processes like lymphoma or undifferentiated carcinoma. On neck exploration it was difficult to find the facial planes as there was diffuse infiltration of the strap muscles and surrounding soft tissues. Whole of the thyroid gland was so hard and infiltrative to surrounding tissues that we did only resection of the isthmic area to avoid any surgical morbidity and sent the removed tissue for frozen section examination due to suspicion of anaplastic carcinoma. The results of the frozen section demonstrated that there were no malignant epithelial cells and only fibrosis with plasma-lymphocytic infiltration could be seen. As there was diffuse extra thyroidal infiltration into the surrounding vital structures, further surgical resection was avoided to prevent fatal complications. Postoperative period was uneventful. Final histopathology of thyroid gland showed diffuse and extensive fibrosis with marked infiltration of chronic inflammatory cells and blood vessels were damaged by the extensive fibrosis (Figs. 3 and 4). The final diagnosis of Riedel’s thyroiditis was made. She was subsequently started on high dose prednisolone i e 80 mg/day. After four weeks, there was marked reduction of the size of the swelling and the sensation of the strangulation of the neck. Within two weeks of
Fig. 3 Low power view of the surgical pathology specimen showing extensive (hematoxylin-eosin stain) bands of fibrosis with plasma cells and lymphocytic infiltration consistent with riedels thyroiditis
Indian J Surg Oncol (September 2016) 7(3):359–362
Fig. 4 High power view of the surgical pathology specimen showing extensive bands of fibrosis with plasma cells and lymphocytic infiltration consistent with riedels thyroiditis (hematoxylin-eosin stain)
starting steroids, the ESR was noted to have fallen to 10 mm/h. Prednisolone was gradually tapered over 6 months and replaced by tamoxifen 10 mg. After two years of follow up she is asymptomatic and recent thyroid USG shows only 0.5 cm swelling left side which has been static from past one and half years.
Comment Riedel’s thyroiditis is a rare fibrotic condition which not only involves the thyroid gland but also infiltrates the important surrounding structures in the neck [1, 2]. The etiology of this disease is far from clear, but the current view favors it to be a localized manifestation of the generalized fibro-inflammatory process that also involves other organs of the body [3, 4]. We report a case of riedel’s thyroiditis which mimicked anaplastic thyroid carcinoma both clinically and radio-logically. Our aim is not only to highlight a very rare presentation, but also to stress the difficulty in diagnosis, evaluation and medical management of this rare entity to avoid high morbidity and possible mortality with the surgical intervention in such a case. Fine needle aspiration cytology, particularly USG guided is an efficient tool for diagnosing thyroid masses, but Riedel’s thyroiditis usually cannot be diagnosed accurately by preoperative FNA [5]. It is difficult for pathologists and radiologists to diagnose the condition and rule out malignancy as is highlighted by our case where both the FNAC and Tru cut biopsy were not able to give a clear cut diagnosis. On the other hand various imaging modalities, including US, CT, MRI, and PET, can be performed for the diagnosis of riedel’s thyroiditis, but may not be helpful for the definitive diagnosis of Riedel’s thyroiditis and differentiation from thyroid malignancy [6].The only way to arrive at a conclusive diagnosis is histopathology from an open biopsy, or after decompressive goiter surgery performed for clinical symptoms [6]. To avoid any aggressive surgical intervention which will be potentially morbid, Riedel’s thyroiditis must be differentiated histologically from malignancies, especially anaplastic thyroid cancer,
361
thyroid lymphoma, sarcoma and fibrosing variant of Hashimoto’s thyroiditis. There is no agreed standard treatment for Riedel’s thyroiditis. Surgical intervention should be limited to debulking, mostly isthmusectomy to relieve constrictive pressure on trachea. Total thyroidectomy should be avoided in cases with diffuse extrathyroidal fibrosis as any surgical intervention will be highly morbid as identification and preservation of vital structures like recurrent laryngeal nerve and parathyroid glands will be difficult [7]. Medical management of the condition, although not supported by controlled trials is considered as treatment of choice to reverse and arrest the fibrotic process. High dose glucocorticoids are usually the first step in the medical management of the patient with the established diagnosis of Riedel’s thyroiditis and cause dramatic improvement in symptoms [8]. Various reports document positive results of glucocorticoids with doses from 15 to 60 mg of prednisone per day. Tamoxifen has also been reported to be an effective medical intervention in Riedel’s thyroiditis as well as other forms of the underlying multifocal fibrosis. [9] Proposed mechanisms of positive action of tamoxifen in this and associated inflammatory conditions involve the induction of autocrine secretion of TGF-β1 as observed in both estrogen receptor-positive and -negative tumor samples in vitro [9]. A recent report demonstrates significant reduction of goiter size using a combination of mycophenolate mofetil (1 g twice daily) and 100 mg prednisone daily in a case that failed to respond to the tamoxifen and prednisolone [10]. Low-dose irradiation has also been attempted in patients with Riedel’s thyroiditis.
Conclusions Riedel’s thyroiditis should be suspected in patients presenting with a hard thyroid mass with compressive symptoms. Surgical intervention should be restricted to obtain tissue for diagnosis and rule out malignancy. Extensive surgery due to potential risk of complications should be avoided. Medical management like high dose glucocorticoids followed by tamoxifen should be used to control inflammatory fibrotic process. Optimal dose and duration of anti-inflammatory treatment needs to be studied and needs further research. Consent The informed consent was obtained from the patient for the publication of this report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Competing interests The authors declare that they have no competing interests.
362
Indian J Surg Oncol (September 2016) 7(3):359–362
Authors’ contributions AHH wrote the draft of the article. SKC had been involved in the diagnostic pathology. IHH and FJW helped in the final writing of the paper and gave final approval of the article. AHH, IHH, SKC and FJW participated in the article revision. All authors read and approved the final manuscript.
4.
5. Financial Support None. 6. 7.
References 8. 1.
2.
3.
Riedel BMCL (1896) Die chronische, zur bildung eisenharter tumoren fuhrende entzundung der schilddruse. Verh Dtsch Ges Pathol Chir 26:101 Sheu SY, Schmid KW (2003) Inflammatory diseases of the thyroid gland. epidemiology, symptoms and morphology. Pathologe 24: 339–347 de Lange WE, Freling NJ, Molenaar WM, Doorenbos H (1989) Invasive fibrous thyroiditis (Riedel’s struma): a manifestation of
9. 10.
multifocal fibrosclerosis? A case report with review of the literature. Q J Med 72:709–717 Zimmermann-Belsing T, Feldt-Rasmussen U (1994) Riedel’s thyroiditis: an autoimmune or primary fibrotic disease? J Intern Med 235:271–274 Guimaraes VC. Subacute and Reidel’s thyroiditis. In: Jameson JL, De Groot LJ, eds. Endocrinology: adult and pediatric. 6th ed. Philadelphia: Elsevier 2010 1600–1603 Pi GY, Lee YS, Hong SW, Chang HS, Park CS (2012) A case of Riedel's thyroiditis. J Korean Surg Soc 82(5):317–320 Fatourechi MM, Hay ID, McIver B, Sebo TJ, Fatourechi V (2011) Invasive fibrous thyroiditis (Riedel’s thyroiditis): the Mayo Clinic experience 1976–2008. Thyroid 21:765–772 Perimenis P, Marcelli S, Leteurtre E, Vantyghem MC, JL W’m (2008) Riedel’s thyroiditis: current aspects. Presse Med 37: 1015–1021 Clark CP, Vanderpool D, Preskitt JT (1991) The response of retroperitoneal fibrosis to tamoxifen. Surgery 109:502–506 Levy JM, Hasney CP, Friedlander PL, Kandil E, Occhipinti EA, Kahn MJ (2010) Combined mycophenolate mofetil and prednisone therapy in tamoxifen- and prednisone-resistant Reidel’s thyroiditis. Thyroid 20:105–107
CASE REPORT
Riedel’s Thyroiditis Mimicking as Anaplastic Thyroid Carcinoma: Unusual Presentation Arsheed Hussain hakeem 1 & Sreerenjini Kaithaparambil Chandramathyamma 2 & Imtiyaz Hussain Hakeem 3 & Fozia Jeelani Wani 4 & Ramesh Gomez 5
Received: 30 September 2015 / Accepted: 16 February 2016 / Published online: 24 February 2016 # Indian Association of Surgical Oncology 2016
Abstract Riedel’s thyroiditis is a rare inflammatory process which not only involves thyroid gland but also the surrounding vital structures. It may also be associated with various forms of systemic fibrotic disorders. The exact etiology is not known, but currently most favored view is that of a localized form of systemic fibrotic process. We report a case of Riedel’s thyroiditis in a patient, highlighting a rare presentation mimicking anaplastic carcinoma. Clinical awareness of such presentation of Riedel’s thyroiditis would enhance our ability to make this diagnosis promptly. Apart from avoiding or minimizing aggressive surgical intervention, awareness of
such clinical entity may avoid complications and hence morbidity. Our case also highlights the difficulty in histological diagnosis which is very important to rule out malignancy and avoiding any major surgical intervention fraught with complications. Good response to high dose steroids as seen in our case is the current accepted treatment of choice. Keywords Riedel’s thyroiditis . Thyroid mass . Anaplastic carcinoma
Background Institution where work was done: Apollo cancer Hospital, Hyderabad, India. * Arsheed Hussain hakeem [email protected] Imtiyaz Hussain Hakeem [email protected] Fozia Jeelani Wani [email protected] Ramesh Gomez [email protected]
1
Department of Head and Neck Oncology, Apollo Cancer Hospitals, Hyderabad 500096, India
2
Department of Histopathology, Lakeshore Hospital and Research Center, Maradu Kochi, Kerala, India
3
Department of Internal Medicine, Poplar Bluff Regional Medical Center, MO, USA
4
Department of Gynaecology and Obstetrics, Apollo Hospitals, Hyderabad 500096, India
5
Department of Endocrinology, Lakeshore Hospital and Research Center, Maradu Kochi, Kerala, India
Riedel thyroiditis is a rare fibrotic condition affecting thyroid gland, characterized by replacement of the thyroid parenchyma with fibrosis [1]. This fibrotic process may not be limited to the thyroid only, but invades the surrounding vital structures [2, 4]. The exact etiology of the condition is not known but the current view favors it to be a local manifestation of a systemic fibrotic process or an autoimmune process [3, 4]. The common presentation of the Riedel’s thyroiditis is firm mass of the thyroid with associated symptoms like hoarseness, dyspnea, dysphagia and aphonia, usually caused by local infiltration of the advancing fibrotic process [5]. Infiltration of the surrounding vital structures may cause hypoparathyroidism, compression of the trachea, larynx, carotid sheath and esophagus. It may also cause invasion of strap muscles and fibrotic process may extend to superior mediastinum. We present a rare case of Riedel’s thyroiditis that presented as a diagnostic problem and clinically mimicked anaplastic carcinoma as whole thyroid gland was enlarged and rock hard on palpation and immobile due to infiltration into the surrounding structures. Clinical awareness of such a unique and rare presentation of Riedel’s thyroiditis should help us to make this diagnosis promptly. It will not only help in diagnosis but also alert the clinician to
360
Indian J Surg Oncol (September 2016) 7(3):359–362
minimize overly aggressive surgical intervention, thus avoiding complications and morbidity. Our case also highlights the good response to the steroids which may greatly enhance the clinical outcome.
Case Presentation A 50 year-old female, known case of hypothyroidism was referred to our head and neck clinic for long standing swelling lower neck with rapid increase in size from past 4 months. The main symptom associated was feeling of strangulation of the neck. It was not associated with dysphagia or hoarseness. There were no definite symptoms of inflammation like pain, edema, fever, malaise, or myalgias. She had undergone total hysterectomy for benign uterine ailment 10 years ago. On palpation of the neck there was a large swelling in the lower midline neck moving with deglutition. It was hard in consistency, most likely arising from the thyroid gland and involved both lobes of the thyroid gland and isthmus. Although the upper margin was distinct, the lower margin was not felt as the mass extended below clavicles on the both sides. There were no palpable lymph nodes in the neck or any other part of the body. Thyroid function test showed hypothyroidism: T3 of 52.3 ng/ dL (71 to 161 ng/dL), free T4 of 0.3 ng/dL (0.8 to 1.7 ng/dL), thyroid stimulating hormone (TSH) of 55 IU/mL (0.86 to 4.69 μIU/mL). Magnetic resonance imaging showed a diffusely enlarged mass involving both thyroid lobes and isthmus, extending to the infra- hyoid level and encircling the trachea and thyroid cartilage (Fig. 1). Magnetic resonance imaging also demonstrated that thyroid mass was homogeneously hypointense on both T1- and T2-weighted images (Figs. 1 and 2). There was no evidence of tracheal invasion on MRI. FNAC and Tru cut biopsy showed only plasma-lymphocytic infiltrates and malignant neoplasm such as anaplastic carcinoma could not be ruled out. The clinical features were favouring anaplastic transformation of longstanding thyroid nodular disease. Open
Fig. 1 Axial T1 weighted magnetic resonance imaging demonstrating homogeneously hypo-intense mass involving whole of thyroid gland and encasing the trachea
Fig. 2 Axial T2 weighted magnetic resonance imaging demonstrating homogeneously hypo-intense mass involving whole of thyroid gland and encasing the trachea
thyroid biopsy was performed to diagnose and also to rule out other malignant processes like lymphoma or undifferentiated carcinoma. On neck exploration it was difficult to find the facial planes as there was diffuse infiltration of the strap muscles and surrounding soft tissues. Whole of the thyroid gland was so hard and infiltrative to surrounding tissues that we did only resection of the isthmic area to avoid any surgical morbidity and sent the removed tissue for frozen section examination due to suspicion of anaplastic carcinoma. The results of the frozen section demonstrated that there were no malignant epithelial cells and only fibrosis with plasma-lymphocytic infiltration could be seen. As there was diffuse extra thyroidal infiltration into the surrounding vital structures, further surgical resection was avoided to prevent fatal complications. Postoperative period was uneventful. Final histopathology of thyroid gland showed diffuse and extensive fibrosis with marked infiltration of chronic inflammatory cells and blood vessels were damaged by the extensive fibrosis (Figs. 3 and 4). The final diagnosis of Riedel’s thyroiditis was made. She was subsequently started on high dose prednisolone i e 80 mg/day. After four weeks, there was marked reduction of the size of the swelling and the sensation of the strangulation of the neck. Within two weeks of
Fig. 3 Low power view of the surgical pathology specimen showing extensive (hematoxylin-eosin stain) bands of fibrosis with plasma cells and lymphocytic infiltration consistent with riedels thyroiditis
Indian J Surg Oncol (September 2016) 7(3):359–362
Fig. 4 High power view of the surgical pathology specimen showing extensive bands of fibrosis with plasma cells and lymphocytic infiltration consistent with riedels thyroiditis (hematoxylin-eosin stain)
starting steroids, the ESR was noted to have fallen to 10 mm/h. Prednisolone was gradually tapered over 6 months and replaced by tamoxifen 10 mg. After two years of follow up she is asymptomatic and recent thyroid USG shows only 0.5 cm swelling left side which has been static from past one and half years.
Comment Riedel’s thyroiditis is a rare fibrotic condition which not only involves the thyroid gland but also infiltrates the important surrounding structures in the neck [1, 2]. The etiology of this disease is far from clear, but the current view favors it to be a localized manifestation of the generalized fibro-inflammatory process that also involves other organs of the body [3, 4]. We report a case of riedel’s thyroiditis which mimicked anaplastic thyroid carcinoma both clinically and radio-logically. Our aim is not only to highlight a very rare presentation, but also to stress the difficulty in diagnosis, evaluation and medical management of this rare entity to avoid high morbidity and possible mortality with the surgical intervention in such a case. Fine needle aspiration cytology, particularly USG guided is an efficient tool for diagnosing thyroid masses, but Riedel’s thyroiditis usually cannot be diagnosed accurately by preoperative FNA [5]. It is difficult for pathologists and radiologists to diagnose the condition and rule out malignancy as is highlighted by our case where both the FNAC and Tru cut biopsy were not able to give a clear cut diagnosis. On the other hand various imaging modalities, including US, CT, MRI, and PET, can be performed for the diagnosis of riedel’s thyroiditis, but may not be helpful for the definitive diagnosis of Riedel’s thyroiditis and differentiation from thyroid malignancy [6].The only way to arrive at a conclusive diagnosis is histopathology from an open biopsy, or after decompressive goiter surgery performed for clinical symptoms [6]. To avoid any aggressive surgical intervention which will be potentially morbid, Riedel’s thyroiditis must be differentiated histologically from malignancies, especially anaplastic thyroid cancer,
361
thyroid lymphoma, sarcoma and fibrosing variant of Hashimoto’s thyroiditis. There is no agreed standard treatment for Riedel’s thyroiditis. Surgical intervention should be limited to debulking, mostly isthmusectomy to relieve constrictive pressure on trachea. Total thyroidectomy should be avoided in cases with diffuse extrathyroidal fibrosis as any surgical intervention will be highly morbid as identification and preservation of vital structures like recurrent laryngeal nerve and parathyroid glands will be difficult [7]. Medical management of the condition, although not supported by controlled trials is considered as treatment of choice to reverse and arrest the fibrotic process. High dose glucocorticoids are usually the first step in the medical management of the patient with the established diagnosis of Riedel’s thyroiditis and cause dramatic improvement in symptoms [8]. Various reports document positive results of glucocorticoids with doses from 15 to 60 mg of prednisone per day. Tamoxifen has also been reported to be an effective medical intervention in Riedel’s thyroiditis as well as other forms of the underlying multifocal fibrosis. [9] Proposed mechanisms of positive action of tamoxifen in this and associated inflammatory conditions involve the induction of autocrine secretion of TGF-β1 as observed in both estrogen receptor-positive and -negative tumor samples in vitro [9]. A recent report demonstrates significant reduction of goiter size using a combination of mycophenolate mofetil (1 g twice daily) and 100 mg prednisone daily in a case that failed to respond to the tamoxifen and prednisolone [10]. Low-dose irradiation has also been attempted in patients with Riedel’s thyroiditis.
Conclusions Riedel’s thyroiditis should be suspected in patients presenting with a hard thyroid mass with compressive symptoms. Surgical intervention should be restricted to obtain tissue for diagnosis and rule out malignancy. Extensive surgery due to potential risk of complications should be avoided. Medical management like high dose glucocorticoids followed by tamoxifen should be used to control inflammatory fibrotic process. Optimal dose and duration of anti-inflammatory treatment needs to be studied and needs further research. Consent The informed consent was obtained from the patient for the publication of this report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Competing interests The authors declare that they have no competing interests.
362
Indian J Surg Oncol (September 2016) 7(3):359–362
Authors’ contributions AHH wrote the draft of the article. SKC had been involved in the diagnostic pathology. IHH and FJW helped in the final writing of the paper and gave final approval of the article. AHH, IHH, SKC and FJW participated in the article revision. All authors read and approved the final manuscript.
4.
5. Financial Support None. 6. 7.
References 8. 1.
2.
3.
Riedel BMCL (1896) Die chronische, zur bildung eisenharter tumoren fuhrende entzundung der schilddruse. Verh Dtsch Ges Pathol Chir 26:101 Sheu SY, Schmid KW (2003) Inflammatory diseases of the thyroid gland. epidemiology, symptoms and morphology. Pathologe 24: 339–347 de Lange WE, Freling NJ, Molenaar WM, Doorenbos H (1989) Invasive fibrous thyroiditis (Riedel’s struma): a manifestation of
9. 10.
multifocal fibrosclerosis? A case report with review of the literature. Q J Med 72:709–717 Zimmermann-Belsing T, Feldt-Rasmussen U (1994) Riedel’s thyroiditis: an autoimmune or primary fibrotic disease? J Intern Med 235:271–274 Guimaraes VC. Subacute and Reidel’s thyroiditis. In: Jameson JL, De Groot LJ, eds. Endocrinology: adult and pediatric. 6th ed. Philadelphia: Elsevier 2010 1600–1603 Pi GY, Lee YS, Hong SW, Chang HS, Park CS (2012) A case of Riedel's thyroiditis. J Korean Surg Soc 82(5):317–320 Fatourechi MM, Hay ID, McIver B, Sebo TJ, Fatourechi V (2011) Invasive fibrous thyroiditis (Riedel’s thyroiditis): the Mayo Clinic experience 1976–2008. Thyroid 21:765–772 Perimenis P, Marcelli S, Leteurtre E, Vantyghem MC, JL W’m (2008) Riedel’s thyroiditis: current aspects. Presse Med 37: 1015–1021 Clark CP, Vanderpool D, Preskitt JT (1991) The response of retroperitoneal fibrosis to tamoxifen. Surgery 109:502–506 Levy JM, Hasney CP, Friedlander PL, Kandil E, Occhipinti EA, Kahn MJ (2010) Combined mycophenolate mofetil and prednisone therapy in tamoxifen- and prednisone-resistant Reidel’s thyroiditis. Thyroid 20:105–107
