Retracting the thyroid matters: Who develops asymptomatic transient thyrotoxicosis after parathyroidectomy.

BACKGROUND: Hyperthyroidism after parathyroidectomy is not a well-understood complication. We sought to determine the incidence and risk factors of hyperthyroidism after parathyroidectomy. MATERIALS AND METHODS: This is a prospective study of 91 patients undergoing parathyroidectomy. Pre- and post-operative thyroid-stimulating hormone(TSH) and free thyroxine(T4) levels at two-week follow-ups were collected. Bivariate analyses were conducted to compare demographics, laboratory results, and intraoperative findings between patients with normal and suppressed post-parathyroidectomy TSH. RESULTS: Twenty-two(24.2 â€‹%) patients had suppressed TSH after parathyroidectomy and 2(2.2 â€‹%) reported symptoms of hyperthyroidism. All hyperthyroidism resolved within 6 weeks. No patients required medical treatment. Compared to the normal TSH group, the suppressed TSH group had significantly more bilateral explorations(91.0 â€‹% vs. 58.0 â€‹%, p â€‹= â€‹0.006), and superior parathyroid resections(95.5 â€‹% vs. 65.2 â€‹%, p â€‹= â€‹0.006). CONCLUSION: Transient hyperthyroidism is common following parathyroidectomy, which is likely associated with intraoperative thyroid manipulation. Gentle retraction of thyroid glands in parathyroidectomy is warranted, especially during superior parathyroid gland resection.

Hyperthyroidism: A Review.

Importance: Overt hyperthyroidism, defined as suppressed thyrotropin (previously thyroid-stimulating hormone) and high concentration of triiodothyronine (T3) and/or free thyroxine (FT4), affects approximately 0.2% to 1.4% of people worldwide. Subclinical hyperthyroidism, defined as low concentrations of thyrotropin and normal concentrations of T3 and FT4, affects approximately 0.7% to 1.4% of people worldwide. Untreated hyperthyroidism can cause cardiac arrhythmias, heart failure, osteoporosis, and adverse pregnancy outcomes. It may lead to unintentional weight loss and is associated with increased mortality. Observations: The most common cause of hyperthyroidism is Graves disease, with a global prevalence of 2% in women and 0.5% in men. Other causes of hyperthyroidism and thyrotoxicosis include toxic nodules and the thyrotoxic phase of thyroiditis. Common symptoms of thyrotoxicosis include anxiety, insomnia, palpitations, unintentional weight loss, diarrhea, and heat intolerance. Patients with Graves disease may have a diffusely enlarged thyroid gland, stare, or exophthalmos on examination. Patients with toxic nodules (ie, in which thyroid nodules develop autonomous function) may have symptoms from local compression of structures in the neck by the thyroid gland, such as dysphagia, orthopnea, or voice changes. Etiology can typically be established based on clinical presentation, thyroid function tests, and thyrotropin-receptor antibody status. Thyroid scintigraphy is recommended if thyroid nodules are present or the etiology is unclear. Thyrotoxicosis from thyroiditis may be observed if symptomatic or treated with supportive care. Treatment options for overt hyperthyroidism from autonomous thyroid nodules or Graves disease include antithyroid drugs, radioactive iodine ablation, and surgery. Treatment for subclinical hyperthyroidism is recommended for patients at highest risk of osteoporosis and cardiovascular disease, such as those older than 65 years or with persistent serum thyrotropin level less than 0.1 mIU/L. Conclusions and Relevance: Hyperthyroidism affects 2.5% of adults worldwide and is associated with osteoporosis, heart disease, and increased mortality. First-line treatments are antithyroid drugs, thyroid surgery, and radioactive iodine treatment. Treatment choices should be individualized and patient centered.

Postoperative Hypocalcemia in Hyperthyroid Patients: The Parathyroids Aren't Always to Blame.

INTRODUCTION: Hypocalcemia is commonly reported after thyroidectomy and has multiple possible etiologies including: parathyroid devascularization, reactive hypoparathyroidism from relative hypercalcemia in thyrotoxicosis, and abrupt reversal of thyrotoxic osteodystrophy. In patients that are actively hyperthyroid and undergoing thyroidectomy, it is not known how many experience hypocalcemia from nonhypoparathyroidism etiologies. Therefore, our aim was to examine the relationship among thyrotoxicosis, hypocalcemia, and hypoparathyroidism. METHODS: A retrospective review was performed of prospectively-collected data from all patients undergoing thyroidectomy for hyperthyroidism by 4 surgeons from 2016 to 2020. All patients carried a diagnosis of Graves' disease or toxic multinodular goiter. Patient demographics, preoperative medications, laboratory reports, and postoperative medications were reviewed. Hypocalcemia within the first month of surgery despite a normal parathyroid hormone (PTH) level was the primary outcome of interest and was compared between patients with and without thyrotoxicosis. Secondary outcomes were duration of postoperative calcium use and the relationship between preoperative calcium supplementation and postoperative calcium supplementation. Descriptive statistics, Wilcoxon rank-sum, and chi-square tests were used for bivariate analysis, as appropriate. RESULTS: A total of 191 patients were identified, with mean age of 40.5 y (range 6-86). Most patients were female (80%) and had Graves' disease (80%). At the time of surgery, 116 (61%) had uncontrolled hyperthyroidism (thyrotoxic group, Free Thyroxine >1.64 ng/dL or Free Triiodothyronine > 4.4 ng/dL), with the remaining 75 (39%) considered euthyroid. Postoperative hypocalcemia (calcium < 8.4 mg/dL) developed in 27 (14%), while hypoparathyroidism (PTH < 12 pg/mL) was observed in 39 (26%). Thyrotoxic patients comprised a majority of those with hypocalcemia (n = 22, 81%, P = 0.01) and hypoparathyroidism immediately following surgery (n = 14, 77%, P = 0.04). However, a majority of initially hypocalcemic, thyrotoxic patients had normal PTH values within the first month after surgery (n = 17, 85%), pointing to a potential nonparathyroid etiology. On bivariate analysis, no significant relationship was found for thyrotoxic patients with initial postoperative hypocalcemia (18%) and hypoparathyroidism <1-month after surgery (29%, P = 0.29) or between 1 and 6 mo after surgery (2%, P = 0.24). Of the 19 patients in the nonhypoparathyroidism group, 17 (89%) were off all calcium supplements by 6 mo postop. CONCLUSIONS: In patients with hyperthyroidism, those in active thyrotoxicosis at time of surgery have a higher rate of postoperative hypocalcemia compared to euthyroid patients. When hypocalcemia lasts >1 mo postoperatively, data from this study suggest that hypoparathyroidism may not be the primary etiology in many of these patients, who typically require calcium supplementation no more than 6 mo postoperatively.

Graves' thyrotoxicosis soon after hemithyroidectomy for low-risk papillary thyroid carcinoma.

Hyperthyroidism is a medical problem that is commonly encountered by emergency physicians, internists and endocrinologists. The development of hyperthyroidism in the postoperative setting of hemithyroidectomy is quite rare. Reported causes include destructive thyroiditis and inappropriate thyroid hormone replacement. Here we report a case of Graves' disease causing thyrotoxicosis soon after surgery in a woman who underwent hemithyroidectomy for low-risk papillary thyroid carcinoma.

Thyrotoxicosis following SARS-COV-2 vaccination: a case series and discussion.

AIM: To describe a case series of thyrotoxicosis likely triggered by SARS-CoV-2 vaccination and to warn physicians about this potential correlation. To report clinical, laboratory and imaging findings and provide further information that goes in line with the underlying mechanisms. METHODS: Single-center case series based on all the information collected in the hospital medical records, as well as the temporal sequence between the onset of symptoms and COVID-19 vaccination. RESULTS: We report 8 cases with thyrotoxicosis after SARS-CoV-2 vaccination. 4 cases of Graves' disease (GD), 2 cases of subacute painful thyroiditis (SAT), 1 case of concurrent GD and SAT and 1 case of atypical subacute thyroiditis. Five patients received BNT162b2 mRNA vaccine, 3 patients 1273 mRNA vaccine. The onset of symptoms following vaccination ranged from 10 to 14 days in six of eight patients and from 7 to 8 weeks in two patients. CONCLUSIONS: Several hypotheses have been proposed to explain the potential correlation between SARS-CoV-2 vaccination and thyrotoxicosis, including immune system hyper-stimulation, molecular mimicry and Autoimmune/Autoinflammatory Syndrome Induced by Adjuvants (ASIA). We should pay greater attention to thyroid disorders in patients receiving vaccine against SARS-CoV-2.

Silent thyroiditis following vaccination against COVID-19: report of two cases.

PURPOSE: It is well established that thyroiditis and other thyroid disorders can be induced by COVID-19 infection, but there is limited information about the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. We report two cases of thyrotoxicosis following SARS-CoV-2 vaccine. METHODS AND RESULTS: Two young health care peoples (wife and husband) received a first dose of SARS-CoV-2 vaccine, and few weeks later developed clinical manifestations of thyroid hyperactivity, with increased thyroid hormone levels on thyroid function tests, suppressed thyroid-stimulating hormone and negative antithyroid antibodies, despite being healthy before vaccination. They were diagnosed at the 4th week after first dose of SARS-Cov-2 vaccine as silent thyroiditis and followed without treatment, since their symptoms were not severe. At the 6th week, the patients became wholly asymptomatic and their thyroid function returned to normal. CONCLUSIONS: Thyrotoxicosis can occur after SARS-CoV-2 vaccination probably related to silent thyroiditis.

Can Pretreatment Serum Beta-hCG be Used for Predicting Thyrotoxicosis in Gestational Trophoblastic Disease?

BACKGROUND: Gestational trophoblastic disease (GTD) comprises a diverse spectrum of entities of abnormal cellular proliferations originating in placental trophoblasts. The specific marker of GTD is beta-hCG which has a similar structure to the TSH molecule, interfering level of thyroid hormones. How and when to check for thyroid function test during this period remain challenging. OBJECTIVE: To assess values of pretreatment beta-hCG and its benefit for predicting thyrotoxicosis among patients with diagnoses of GTD. METHODS: Retrospective analytical study included all women diagnosed with GTD at Lampang Hospital from January 2010 to May 2020. The patients' pretreatment beta-hCG and thyroid function were collected. Sensitivity and specificity for detecting laboratory hyperthyroidism were reported and classified by pretreatment beta-hCG levels. RESULTS: Forty-four women with diagnoses of GTD were recruited. The range of pretreatment beta-hCG levels were classified  into 4 groups: beta-hCG > 50,000 IU/ml (group 1), beta-hCG > 100,000 IU/ml (group 2), beta-hCG > 150,000 IU/ml (group 3), beta-hCG > 200,000 IU/ml (group 4). The sensitivity for prediction of high fT4 were 100%, 94.1%, 94.1% and 88.2% in group 1,2,3 and 4, respectively, while the specificity were 12%, 20%, 32% and 44% in group 1,2,3 and 4, respectively. CONCLUSION: Pretreatment beta-hCG > 100,000 uIU/ml has the high sensitivity and acceptable specificity for predicting hyperthyroidism. So we don't need to check or wait for thyroid function test in patients who had beta-hCG < 100,000 IU/ml.

Tirotoxicosis por enfermedad trofoblástica gestacional: revisión a partir de 3 casos / Thyrotoxicosis due to gestational trophoblastic disease: clinical cases

La enfermedad trofoblástica gestacional (ETG) es una complicación del embarazo poco común. Corresponde a un espectro de lesiones proliferativas del tejido trofoblástico: Mola Hidatiforme (MH) en sus formas parcial y completa, Coriocarcinoma, Tumor Trofoblástico y Tumor Trofoblástico Epiteloide. Los distintos tipos de ETG presentan en común la hipersecreción de gonadotrofina coriónica humana (hCG). La hCG es una hormona glicoproteica con una estructura muy similar a la TSH, por lo cual puede estimular la función tiroidea en condiciones fisiológicas y en algunas condiciones patológicas. La ETG puede cursar con hipertiroidismo, el cual puede variar en intensidad, desde una presentación asintomática con alteración leve de hormonas tiroideas a un cuadro de hipertiroidismo manifiesto. Se presentan 3 casos clínicos de pacientes con ETG, específicamente MH que evolucionaron con tirotoxicosis transitoria. Los casos presentaron un cuadro leve de hipertiroidismo con pocos síntomas asociados. La taquicardia fue el único síntoma en la mayoría de los casos. En todas las pacientes las hormonas tiroideas se normalizaron después del tratamiento de la ETG. Conclusión: Se debe tener presente la posibilidad de hipertiroidismo en toda paciente con ETG. Un alto nivel de sospecha permitirá identificar a aquellas pacientes que cursen con hipertiroidismo, permitiendo así un diagnóstico y tratamiento oportuno.

Gestational trophoblastic disease (GTD) is a rare complication of pregnancy. GTD includes a group of proliferative lesions of trophoblastic tissue: partial and complete hydatidiform mole, choriocarcinoma, epithelioid trophoblastic tumor, and placental site trophoblastic tumor. The different types of GTD have in common the hypersecretion of human chorionic gonadotropin (hCG). HCG is a glycoprotein hormone with a similar structure to TSH. In physiological and pathological conditions hCG can stimulate thyroid function. GTD can present with hyperthyroidism, which can vary in intensity, from an asymptomatic presentation with mild alteration of thyroid hormones to a manifest hyperthyroidism. We present 3 clinical cases of patients with GTD thyrotoxicosis. All cases presented mild hyperthyroidism. Tachycardia was the only symptom in most cases. In all patients thyroid hormones return to normal after treatment of GTD. Conclusion: In patients with GTD the possibility of hyperthyroidism should be kept in mind. A high level of suspicion will allow to identifying patients with hyperthyroidism.

Thyroid disorders and SARS-CoV-2 infection: From pathophysiological mechanism to patient management.

The World Health Organization (WHO) declared the COVID-19 epidemic to be a global pandemic in March 2020. COVID-19 is an infection caused by SARS-CoV-2, a coronavirus that utilizes the angiotensin-2 converting enzyme to penetrate thyroid and pituitary cells, and may result in a "cytokine storm". Based on the pathophysiological involvement of the pituitary-thyroid axis, the current review discusses the diagnosis of abnormal thyroid function test, and the management of patients presenting with thyrotoxicosis, thyroid-associated orbitopathy and hypothyroidism in the context of SARS-CoV-2 infection.

A remarkable case of thyrotoxicosis initially caused by graves' disease followed by a probable TSHoma - a case report.

BACKGROUND: Graves' disease is the commonest cause of thyrotoxicosis whilst thyrotropin (TSH)-producing pituitary adenomas (thyrotropinomas, TSHomas) are very rare and account for just 1-2% of all pituitary adenomas. Coexistence of a TSHoma and Graves' disease has been very rarely reported. Here, we report a case of a patient whose initial presentation with primary thyrotoxicosis due to Graves' disease, was subsequently followed by a relapse of thyrotoxicosis due to a probable TSHoma. CASE: A sixty-eight year old woman was referred to our department with classical features of thyrotoxicosis. Initial biochemistry confirmed hyperthyroxinaemia [free thyroxine (fT4) 20.4 pmol/L (reference range 7.0-16.0)] and a suppressed TSH [< 0.02mIU/L (0.50-4.20)]. A technetium pertechnetate uptake scan was consistent with Graves' Disease. She was treated with carbimazole for 18 months and remained clinically and biochemically euthyroid. After stopping carbimazole her fT4 started to rise but TSH remained normal. Laboratory assay interference was excluded. A TRH stimulation test demonstrated a flat TSH response and pituitary MRI revealed a microadenoma. Remaining pituitary hormones were in the normal range other than a slightly raised IGF-1. An 11C-methionine PET/CT scan coregistered with volumetric MRI (Met-PET-MRICR) demonstrated high tracer uptake in the left lateral sella region suggestive of a functioning adenoma. The patient declined surgery and was unable to tolerate cabergoline or octreotide. Thereafter, she has elected to pursue a conservative approach with periodic surveillance. CONCLUSION: This is a very unusual case of thyrotoxicosis caused by two different processes occurring in the same patient. It highlights the importance of considering dual pathology when previously concordant thyroid function tests become discordant. It also highlights a potential role of Met-PET-MRICR in the localisation of functioning pituitary tumours.

A systematic review of the incidence of thyroid carcinoma in patients undergoing thyroidectomy for thyrotoxicosis.

INTRODUCTION: Hyperthyroidism (HT) has been associated with no insignificant rates of thyroid malignancy. There are no current specific guidelines that suggest routine preoperative imaging for thyroid nodules in patients with Grave's disease. We therefore performed a systematic review assessing rates of thyroid malignancy in patients undergoing surgery for different causes of HT: Grave's disease (GD), toxic adenoma (TA) and toxic multinodular goitre (TMNG). METHODS: Major databases (MEDLINE, PubMed and the Cochrane library) were searched to identify eligible studies. RESULTS: After searching and appraising, 33 papers were found to be eligible for analysis. The mean overall rate of malignancy was 8.5% (range 0.8%-32.4%). The mean rates based on histological subtype were as follows: papillary thyroid cancer (PTC), 3.1% (range 0%-13.2%); micropapillary carcinoma (mPTC), 5.1% (range 0%-16.9%); and follicular thyroid cancer (FTC), 0.8% (range 0%-4.4%). In those patients who had preoperative imaging, mean malignancy rates were higher in patients with pre-identified nodules (19.8%) compared to those without any nodules (8.7%). Mean rates were lower in patients with GD/diffuse goitre (5.9%) compared to patients with TA (6.5%) and TMNG (12%). CONCLUSION: Hyperthyroidism is associated with notable rates of thyroid cancer, although the mechanisms for this are not clear. The presence of nodules increases this risk. This review raises the question for considering preoperative assessment of nodules in all patients undergoing surgery for HT, in order to correctly assess and evaluate any patients with suspected concurrent thyroid malignancy, before proceeding with surgery.

Case report of a suspected pheochromocytoma co-presenting with a glioblastoma multiforme: case report and review of the literature.

The combination of a pheochromocytoma with any brain neoplasm is a rare occurrence, to our knowledge, this is the first reported case of a glioblastoma multiforme co-presenting with undiagnosed pheochromocytoma.

[Thyroid dysfunctions secondary to cancer immunotherapy]. / Les dysthyroïdies sous immunothérapie anti-cancéreuse.

The immune checkpoint inhibitors (CPI) such as anti-PD(L)1 or anti-CTLA4 had improved long-term patients' outcomes in different malignancies. Thyroid disorders are the most frequent endocrine side effects from CPI reported in clinical trials and in clinical routine practice. The incidence of thyroid dysfunction is variable according to ICP used (more frequent under anti-programmed cell death 1 (PD1) or anti-programmed cell death-ligand 1 (PDL1)). Most thyroid dysfunctions have been reported to occur 2 to 4 courses after CPI initiation. The clinical symptoms are generally nonspecific (asthenia, weight change, rarely cardiac rhythm disorder). These thyroid dysfunctions are commonly painless thyroiditis with a biphasic evolution: thyrotoxicosis followed by a secondary hypothyroidism frequently definitive. Diagnosis is made on a thyroid test (TSH and FT4). In most cases, no further exam is necessary. Beta blockers therapy is recommended in symptomatic thyrotoxicosis with palpitations. Thyroid hormones therapy will be introduced quickly in case of hypothyroidism. Thyroid dysfunctions are not a contra-indication to the continuation of immunotherapy. Due to the high frequency of these complications, close monitoring of the thyroid status is recommended under CPI.

Uncommon Association Between Diabetic Ketoacidosis, Thyrotoxicosis, Cutaneous Abscess and Acute Pericarditis in an Immunocompetent Patient: A Single Case Report and Literature Review.

INTRODUCTION: The typical factors precipitating diabetic ketoacidosis (DKA) include infections (30%), cessation of antidiabetic medication (20%), and a new diagnosis of diabetes (25%). The etiology remains unknown in 25% of cases. Less frequent causes cited in the literature include severe thyrotoxicosis and, infrequently, pericarditis. Few publications have described the role of human T lymphotropic virus type 1 (HTLV-1) in endocrine and metabolic disorders. Based on a clinical case associated with several endocrine and metabolic disorders, we suggest a potential role for HTLV-1, an endemic virus in the Amazonian area, and review the literature concerning the role of this virus in thyroiditis, pericarditis and diabetes mellitus. CASE REPORT: A fifty-year-old Surinamese woman without any medical history was admitted for diabetic ketoacidosis. No specific anti-pancreatic autoimmunity was observed, and the C-peptide level was low, indicating atypical type-1 diabetes mellitus. DKA was associated with thyrotoxicosis in the context of thyroiditis and complicated by nonbacterial pericarditis and a Staphylococcus aureus subcutaneous abscess. The patient was infected with HTLV-1. CONCLUSION: To our knowledge, this uncommon association is described for the first time. Few studies have analyzed the implications of HTLV-1 infection in thyroiditis and diabetes mellitus. We did not find any reports describing the association of pericarditis with HTLV-1 infection. Additional studies are necessary to understand the role of HTLV-1 in endocrine and cardiac disorders.

Hipertiroidismo en personas mayores de 65 años: serie de casos de un hospital universitario / Thyrotoxicosis in the elderly: case series report from a university hospital

Introducción: En Chile en las últimas décadas ha aumentado la población de personas mayores de 65 años. La tirotoxicosis en este grupo está asociada a complicaciones como fibrilación auricular (FA), insuficiencia cardiaca (ICC), osteoporosis y aumento de la mortalidad. En algunos casos puede presentarse con síntomas no específicos, cuadro conocido como hipertiroidismo apático. Objetivos: Evaluar las características clínicas de la tirotoxicosis en personas mayores. Método: Serie de casos retrospectiva. Se analizaron fichas clínicas de pacientes mayores de 65 años con el diagnóstico de tirotoxicosis controlados en nuestro centro entre enero de 2012 y mayo de 2018. Resultados: En el periodo estudiado 54 pacientes fueron diagnosticados de tirotoxicosis. Se excluyen 4 por datos incompletos. El 80% corresponden a mujeres. La mediana de edad fue 71 años (rango 65-94), sin diferencias por género (p=0,61). La etiología más frecuente fue enfermedad de Graves (EG) en 64%, seguido por bocio multinodular hiperfuncionante en 20%, adenoma tóxico en 10% y asociada a fármacos en 6%. De los pacientes con EG, 28% presentó orbitopatía distiroidea (OD) clínicamente evidente. Un 30% se diagnosticó en contexto de baja de peso, deterioro cognitivo o patología cardiovascular, sin presentar síntomas clásicos de hipertiroidismo. Un 16% presentó FA, 14% ICC y 6% fractura osteoporótica. El 28% fue diagnosticado durante una hospitalización o requirió ser hospitalizado durante los meses siguientes. Los mayores de 75 años presentan una mayor probabilidad de hipertiroidismo apático (OR 5,1, IC95% 1,15-22,7 p=0,01). Además, las complicaciones aumentan en mayores de 75 años, encontrándose en este grupo todos los casos de FA. Conclusiones: La etiología más común de tirotoxicosis fue la EG, a diferencia de lo reportado en otras poblaciones. Un número importante de pacientes debutó sin síntomas clásicos de hipertiroidismo, principalmente mayores de 75 años, por lo que se debe tener una alta sospecha en este grupo etario.

Introduction: Hyperthyroidism in the elderly can produce severe complications such as atrial fibrillation (AF), heart failure (CHF) and osteoporosis. In the elderly, thyrotoxicosis may have only nonspecific symptoms, known as apathetic hyperthyroidism. Objective: To evaluate the clinical characteristics of thyrotoxicosis in the elderly. Methods: Retrospective case series. We reviewed clinical records of patients with thyrotoxicosis older than 65 years, between January 2012 and March 2019. Results: During this period, 54 patients were diagnosed with thyrotoxicosis. Four patients were excluded due to incomplete data. 80% were women. The average age was 73 years (range 65-94), without age difference between gender (p=0,61). The most frequent etiology was Graves' disease in 64%. Hyperfunctioning multinodular goiter was confirmed in 20%, toxic adenoma in 10% and drug-associated in 6%. Twenty eight percent of Graves' disease patients had dysthyroid orbitopathy. Thirty percent presented as apathetic hyperthyroidism. Sixteen percent of the patients presented AF, 14% CHF, and 6% osteoporotic fracture. Twenty-eight percent were diagnosed during hospitalization or required hospitalization in the following months. Those older than 75 years had a greater probability of presenting apathetic hyperthyroidism (OR 5.1, 95% CI 1.15- 22.7 p=0.01). Complications increase in this age group, with all cases of AF. Conclusions: The most common etiology of thyrotoxicosis in this group was GD. This differs from other populations. A significant number of patients presented without classic symptoms of hyperthyroidism, especially in people older than 75 years. Special attention should be paid to atypical symptoms of hyperthyroidism in this group.

Subsequent thyroid disorders associated with treatment strategy in head and neck cancer patients: a nationwide cohort study.

BACKGROUND: We investigated the risk of thyroid disorders, namely hypothyroidism, thyrotoxicosis and thyroiditis, in head and neck cancer patients undergoing multimodal treatment. METHODS: A cohort study design using Taiwan's National Health Insurance Research Database was used to assess head and neck cancer patients over 20 years old. The cohort was divided into one group who underwent primary tumor excision only (PTE) and another with additional neck dissection (PTE + ND). The tumor sites were stratified to estimate the tumor-site-specific risk of thyroid disorders. The effect of subsequent resurgery, radiotherapy (RT), chemotherapy (CT), and concomitant (CCRT) or sequential chemoradiation therapy (sequential CT+ RT) on the risk of thyroid disorders was explored. RESULTS: For 1999-2012, 7460 patients who underwent PTE + ND and 3730 who underwent PTE were enrolled and followed-up until the end of 2013. There were 122 and 50 patients in the two groups, respectively, who developed thyroid disorders, with no statistical difference between the groups. Patients with hypopharyngeal, oropharyngeal, or laryngeal cancer in the PTE + ND group had a higher risk of thyroid disorders (adjusted HR: 1.50, 95% CI: 0.67-3.38) than those in the PTE group when adjusted for covariates and mortality. Patients who underwent subsequent RT (adjusted HR: 3.64, 95% CI: 1.05-2.77) and CCRT (adjusted HR: 1.70, 95% CI: 1.05-2.77) after PTE + ND had a significantly higher risk of thyroid disorders. CONCLUSION: RT results in a major risk of subsequent thyroid disorders, and ND may exacerbate this effect. Physicians should monitor thyroid function from two years after treatment initiation, especially in patients who undergo ND and subsequent RT.

Transient thyroiditis after parathyroidectomy for tertiary hyperparathyroidism.

Thyrotoxicosis due to thyroiditis is predominantly caused by infection or autoimmune disease of the thyroid. Parathyroid surgery however, is a lesser known cause of thyroiditis, due to thyroid manipulation. We treated a patient who developed transient symptomatic thyroiditis following parathyroid surgery for tertiary hyperparathyroidism. Therefore, the differential diagnosis for patients with symptoms after parathyroid surgery should include transient thyroiditis.

Papillary thyroid carcinoma in cervical lymph nodes with vanished thyroid gland after ablation of Graves' disease by radioactive iodine.

Primary thyroid carcinoma after thyroid ablation by radioactive iodine is rare. We present a very rare condition of lateral apparent papillary thyroid carcinoma eight years after receiving radioactive iodine for thyrotoxicosis, which led to complete anatomical and functional involution of the thyroid gland.