Evaluation of Betulinic Acid Derivatives as PET Tracers for Hypoxia-Induced Carbonic Anhydrase IX (CA IX) Expression.

Non-invasive visualisation of the expression of hypoxia-related proteins, such as carbonic anhydrase IX (CA IX), by positron emission tomography (PET) could provide important information on the oxygenation status of tumours. Since betulinic acid derivatives bind specifically to CA IX the aim of the study was the development betulinic acid-based 68Ga-labelled PET tracers and to evaluate the hypoxia detecting properties in vitro and in vivo. The binding of betulinic acid (B-DOTA) and betulinyl-3-sulfamate (BS-DOTA) was assessed in two rat tumour cell lines (AT1 prostate and Walker-256 mammary carcinomas). AT1 cells express CA IX in a hypoxia-dependent manner whereas Walker-256 cells, expressing almost no CA IX in wildtype, were transfected with the rat Car9 gene. In vivo measurements were carried out in a small animal PET/CT in AT1 tumours in rats breathing room air, 8% or 100% O2. In AT1 cells hypoxia-induced overexpression of CA IX led to a stronger binding of BS-DOTA but not of B-DOTA. The BS-DOTA binding correlated linearly with the CA IX protein expression and could be blocked by an excess of unlabelled tracer. In the transfected Walker-256 cells no specific binding of either of the tracers was seen. In vivo the intratumoral accumulation of BS-DOTA was increased in animals kept under inspiratory hypoxia and reduced by hyperoxia. Therefore, betulinyl-3-sulfamate could be used as a PET tracer of CA IX expression in tumours and to provide information about the oxygenation status. However, accumulation data indicated that binding not only depends on hypoxia-induce CA IX expression but also on the tumour-line-specific basal expression and on the initial oxygenation status of the tumour.

Improvement in thyroid ultrasound report quality with radiologists' adherence to 2015 ATA or 2017 TIRADS: a population study.

Objectives: There has been slow adoption of thyroid ultrasound guidelines with adherence rates as low as 30% and no population-based studies investigating adherence to guideline-based malignancy risk assessment. We therefore evaluated the impact of adherence to the 2015 ATA guidelines or 2017 ACR-TIRADS guidelines on the quality of thyroid ultrasound reports in our healthcare region. Methods: We reviewed 899 thyroid ultrasound reports of patients who received fine-needle aspiration biopsy and were diagnosed with Bethesda III or IV nodules or thyroid cancer. Ultrasounds were reported by radiology group 1, group 2, or other groups, and were divided into pre-2018 (before guideline adherence) or 2018 onwards. Reports were given a utility score (0-6) based on how many relevant nodule characteristics were included. Results: Group 1 had a pre-2018 utility score of 3.62 and 39.4% classification reporting rate, improving to 5.77 and 97.0% among 2018-onwards reports. Group 2 had a pre-2018 score of 2.8 and reporting rate of 11.5%, improving to 5.58 and 93.3%. Other radiology groups had a pre-2018 score of 2.49 and reporting rate of 32.2%, improving to 3.28 and 61.8%. Groups 1 and 2 had significantly higher utility scores and reporting rates in their 2018-onward reports when compared to other groups' 2018-onward reports, pre-2018 group 1 reports, and pre-2018 group 2 reports. Conclusions: Dedicated adherence to published thyroid ultrasound reporting guidelines can lead to improvements in report quality. This will reduce diagnostic ambiguity and improve clinician's decision-making, leading to overall reductions in unnecessary FNA biopsy and diagnostic surgery.

Myocardial Infarction after Long-Term Treatment with a Tyrosine Kinase Inhibitor (TKI) with Anti-VEGF Receptor Activity.

TKIs including anti-VEGF receptor activity have been approved for the treatment of patients with radioiodine resistant thyroid carcinomas. For lenvatinib arterial thromboembolic events are listed as adverse events of special interest with lenvatinib. In the phase III study, arterial thromboembolic events were reported in 3% of lenvatinib-treated patients and 1% in the placebo group. Most of the patients had predisposing factors. Only one myocardial infarct was reported in the lenvatinib phase III study. We report a 73-year-old female patient with metastatic thyroid papillary carcinoma who was treated with total thyroidectomy. The operation was followed by four radioiodine therapies over a period of 6 years. At 6 years she developed lung metastasis without radioiodine uptake, one solitary liver metastasis and one solitary right renal metastasis. One year after the first diagnosis of radioiodine resistant lung metastasis the lung metastasis showed progression according to RECIST criteria. This treatment was resulting in prolonged partial response with disappearance of a hepatic and renal metastasis. A myocardial infarction occurred after 39 months of lenvatinib treatment resulting in implantation of 3 stents and a two chamber pacemaker. The treatment was discontinued. Except for well controlled hypertension there were neither predisposing diseases like diabetes nor symptoms of cardiac ischemia on exertion. However, the family history for cardiovascular diseases was positive for cardiac infarction reported for one brother. Another brother was treated for hypertension and the patient's mother suffered from a cerebral infarction at the age of 60. While only one myocardial infarct was reported in the lenvatinib phase III study with 392 patients this case suggests that long-term treatment with lenvatinib may be associated with an increased risk for myocardial infarct also in patients with no predisposing diseases except well controlled hypertension and positive family history for cardiovascular diseases.

[Speech therapy after thyroid gland operations in Germany: analysis of routine data from 50,676 AOK patients]. / Logopädie nach Schilddrüsenoperationen in Deutschland: eine Routinedatenanalyse von 50.676 AOK-Patienten.

BACKGROUND: This study investigated the frequency of postoperative speech therapy in the context of vocal cord palsy after thyroid surgery based on nationwide routine data. Additionally, volume-outcome relationships were examined. MATERIAL AND METHODS: Nationwide routine data from insured patients of the Local Health Insurance Fund (AOK) who underwent thyroid surgery for a benign thyroid disease between 2013 and 2015 were analyzed. Postoperative speech therapy was determined based on prescription data. Transient and permanent vocal cord palsy were determined using indicators. The effect of hospital volumes (volume quintiles) on prescription of postoperative speech therapy was determined by multivariate logistic regression. RESULTS: A total of 50,676 thyroid gland operations were identified. The overall frequency of postoperative speech therapy prescription was 6.5%. In AOK patients with transient or permanent vocal cord palsy, the frequencies of postoperative speech therapy prescription were 56.1% and 75.2%, respectively. The prescription volume of the normal case (≥21 units of speech therapy) was exceeded in 0.7% of the AOK patients. In the two lowest case volume categories the risk of postoperative speech therapy exceeding the prescription volume of the normal case was significantly higher compared to the highest case volume hospitals (odds ratios: 1.2 and 1.8, respectively). CONCLUSION: This study presents the reality of healthcare with respect to the frequency of speech therapy prescription after thyroid gland surgery in Germany. In addition, it was determined that the risk of postoperative speech therapy prescription exceeding the volume of the normal case after thyroid gland operations decreases with increasing case volumes of hospitals.

[Complications after thyroid gland operations in Germany : A routine data analysis of 66,902 AOK patients]. / Komplikationen nach Schilddrüsenoperationen in Deutschland : Eine Routinedatenanalyse von 66.902 AOK-Patienten.

BACKGROUND: Routine data from hospitals in the public healthcare system allow the analysis of large patient datasets without generating additional documentation efforts for hospitals. This study reports the frequencies of postoperative complications after thyroid surgery based on routine nationwide data. Moreover, volume-outcome relationships were investigated. MATERIAL AND METHODS: Nationwide routine data from insured patients of the Local Health Insurance Fund (AOK) who underwent thyroid surgery between 2008 and 2010 were analyzed. Complications were determined based on indicators for permanent vocal cord palsy, re-bleeding with re-operations and wound infections with specific treatment. The effect of hospital volumes (volume quintiles) on the indicators was determined by multivariate logistic regression. RESULTS: A total of 66,902 thyroid gland operations were identified. The overall frequency of permanent vocal cord palsy was 1.5 %, re-bleeding 1.8 % and wound infections 0.4 %. In the four lowest case volume categories the risk of permanent vocal cord palsy was significantly higher compared to the highest case volume hospitals (odds ratio 1.5, 1.7, 1.7 and 2.2, respectively). CONCLUSION: This study represents the reality of healthcare for thyroid surgery in Germany. Additionally, it was determined that the risk for permanent vocal cord palsy after thyroid gland operations decreased with increasing case volumes of hospitals.

In vitro anticancer activity of Betulinic acid and derivatives thereof on equine melanoma cell lines from grey horses and in vivo safety assessment of the compound NVX-207 in two horses.

Betulinic acid, a pentacyclic triterpene, and its derivatives are promising compounds for cancer treatment in humans. Melanoma is not only a problem for humans but also for grey horses as they have a high potential of developing melanoma lesions coupled to the mutation causing their phenotype. Current chemotherapeutic treatment carries the risk of adverse health effects for the horse owner or the treating veterinarian by exposure to antineoplastic compounds. Most treatments have low prospects for systemic tumor regression. Thus, a new therapy is needed. In this in vitro study, Betulinic acid and its two derivatives B10 and NVX-207, both with an improved water solubility compared to Betulinic acid, were tested on two equine melanoma cell lines (MelDuWi and MellJess/HoMelZh) and human melanoma (A375) cell line. We could demonstrate that all three compounds especially NVX-207 show high cytotoxicity on both equine melanoma cell lines. The treatment with these compounds lead to externalization of phosphatidylserines on the cell membrane (AnnexinV-staining), DNA-fragmentation (cell cycle analysis) and activation of initiator and effector caspases (Caspase assays). Our results indicate that the apoptosis is induced in the equine melanoma cells by all three compounds. Furthermore, we succeed in encapsulating the most active compound NVX-207 in 2-Hydroxyprolyl-ß-cyclodextrine without a loss of its activity. This formulation can be used as a promising antitumor agent for treating grey horse melanoma. In a first tolerability evaluation in vivo the formulation was administered every one week for 19 consecutive weeks and well tolerated in two adult melanoma affected horses.

Laser capture microdissection is a valuable tool in the preoperative molecular screening of follicular lesions of the thyroid: an institutional experience.

OBJECTIVES: The application of molecular tests to thyroid fine needle aspiration (FNA) has been shown to be a valuable tool to better refine the pre-operative malignant risk of patients with indeterminate cytology results. In this study, we investigated the feasibility of using the laser capture microdissection (LCM) technique to obtain DNA and RNA for molecular tests in routine thyroid FNA smears. METHODS: Nine coupled FNA and histological retrospective cases and 31 prospective FNA cases with a follicular neoplasm/suspicious for a follicular neoplasm (FN/SFN) diagnosis were included in this study. Both cytological and histological specimens were investigated by direct sequencing and reverse transcription-polymerase chain reaction (RT-PCR) for BRAF and RAS mutations and for PAX8/PPARG and RET/PTC rearrangements, respectively. RESULTS: LCM yielded good DNA and RNA quality in all cases (100%) in both series, irrespective of the staining used (Giemsa, Papanicolaou, immunostain for thyroglobulin) and the cytology technique (conventional or liquid-based preparations). Total mutations found in the FNA and in the corresponding histological specimen in both series were: one PAX8/PPARG rearrangement in a follicular carcinoma (FC), four NRAS mutations [in two FCs, one papillary carcinoma and one follicular adenoma (FA)] and one HRAS mutation in one FA. The sensitivity was 67% and the specificity was 91%. CONCLUSIONS: LCM is a valuable tool to obtain good quality DNA and RNA for molecular tests in cytological material from thyroid FNA, and can be a useful option in the management of patients with an FN/SFN FNA diagnosis.

Controversial constitutive TSHR activity: patients, physiology, and in vitro characterization.

G protein-coupled receptors constitute a large family of transmembrane receptors, which activate cellular responses by signal transmission and regulation of second messenger metabolism after ligand binding. For several of these receptors it is known that they also signal ligand-independently. The G protein-coupled thyroid stimulating hormone receptor (TSHR) is characterized by a high level of constitutive activity in the wild type state. However, little is known yet concerning the physiological relevance of the constitutive wild type TSHR activity. Certainly, knowledge of the physiological relevance of constitutive wild type receptor activity is necessary to better understand thyroid physiology and it is a prerequisite for the development of better therapies for nonautoimmune hyperthyroidism and thyroid cancer. Based on a literature search regarding all published TSHR mutations, this review covers several mutations which are clearly associated with a hyperthyroidism-phenotype, but interestingly show a lack of constitutive activity determined by in vitro characterization. Possible reasons for the observed discrepancies between clinical phenotypes and in vitro characterization results for constitutive TSHR activity are reviewed. All current in vitro characterization methods for constitutive TSHR mutations are "preliminary attempts" and may well be revised by more comprehensive and even better approaches. However, a standardized approach for the determination of constitutive activity can help to identify TSHR mutations for which the investigation of additional signaling mechanisms would be most interesting to find explanations for the current clinical phenotype/in vitro discrepancies and thereby also define suitable methods to explore the physiological relevance of constitutive wild type TSHR activity.

[Fine-needle aspiration cytology of thyroid nodules: molecular diagnostics in a routine diagnostic setting]. / Feinnadelzytologie von Schilddrüsenknoten: Molekulare Diagnostik in der klinischen Routine.

BACKGROUND AND OBJECTIVE: Results for the detection of point mutations and rearrangements have thus far been obtained by fresh material of fine needle aspiration cytology (FNAC). After a first retrospective study we report on the diagnostic detection in routinely obtained, consecutive air-dried FNAC smears. METHODS: RNA and DNA was extracted from 154 consecutive routine air-dried FNAC smears: 80 with microfollicular proliferation (MFP), 45 with follicular neoplasia (FN), 26 with the cytological diagnosis of papillary carcinomas (PTC) and 3 which were suspicious for malignancy. PAX8/PPARG and RET/PTC3 rearrangements were detected by qPCR, while BRAF and RAS point mutations were detected by pyrosequencing. RESULTS: Only 0.7 % and 5.3 % of the routine air-dried FNAC samples did not allow analysis of a point mutation or rearrangements, respectively. NRAS mutations could be detected in 7 MFP smears, and in one of FN and PTC samples, respectively. HRAS mutations were detected in one MPF and one FN sample. A KRAS mutation was only detected in one FN sample, whereas BRAF mutations were detected in 20 samples with PTC (but in no other sample). PAX8/PPARG was detected in 2 MFP samples, while RET/PTC was detected in only one MFP sample. In total, 13.8 % MFP-FNAC, 6.7 % FN-FNAC, and 80.8 % PTC-FNAC samples harbored a mutation. CONCLUSION: These results demonstrate that rearrangements and point mutations can be detected in routinely obtained air-dried FNAC samples.

miRNAs with the potential to distinguish follicular thyroid carcinomas from benign follicular thyroid tumors: results of a meta-analysis.

The detection of somatic mutations in indeterminate or follicular proliferation fine-needle aspiration cytologies (FNACs) is able to clarify only a subgroup of those FNACs. Therefore, further markers to differentiate this problematic FNAC category by the identification of mutation negative thyroid cancers and benign nodules are urgently needed. Our objective was to evaluate previously published miRNA markers and discover novel ones from all publicly available miRNA expression profiling data sets. By literature review and data repository search we gathered 3 data sets describing human miRNA expression profiles of follicular thyroid cancer (FTC) and follicular adenoma (FA) samples. Literature review summarized 27 previously published miRNAs, which were validated in the 3 available data sets. By means of uniform statistical analysis 6 further miRNAs were identified and tested in an independent, previously published microarray data set. Meta-analysis confirmed 7 out of 27 previously published, and 4 out of 6 de novo identified miRNAs. The low confirmation rate of previously published miRNA markers was induced by low numbers of samples in the analyzed studies and high false discovery rates that were higher than 0.2. Finally, miR-637, miR-181c-3p, miR-206, and miR-7-5p were discovered as de novo potential FTC markers and validated in at least one independent, previously published data set. Two out of these new identified miRNAs (miR-7-5p and miR-206) were validated by qPCR in an independent sample set of 32 FTC and 46 FA samples. Especially miR-7-5p was able to differentiate benign and malignant thyroid tumors in several datasets.

Impact of different methodologies on the detection of point mutations in routine air-dried fine needle aspiration (FNA) smears.

Currently the best method to select suspicious thyroid nodules for surgery is fine needle aspiration (FNA) cytology. However, FNA cytology has some inherent limitations, which can partly be overcome by molecular analysis. Therefore, molecular testing for somatic mutations has emerged as the most promising approach for molecular FNA diagnostics. The objective of this methodological study was to evaluate the feasibility of detecting BRAF, NRAS, HRAS, and KRAS mutations from routine air-dried thyroid FNA smears, and to find an optimal method for detecting these mutations in FNA samples. DNA was extracted from 110 routine air-dried FNA smears and the corresponding surgically obtained formalin-fixed paraffin-embedded tissues. The presence of BRAF, NRAS, HRAS, and KRAS mutations was assessed by real-time PCRs and high resolution melting analysis, and/or pyrosequencing in comparison to real-time PCRs using hybridization probes and fluorescence melting curve analysis. The high-resolution melting-PCRs revealed a significantly lower number of PCR failures and questionable results, and detected more mutations than the PCRs using hybridization probes. The number of PCR failures ranging from 14-16% by high-resolution melting-PCRs could be further reduced to 5-14% by adding pyrosequencing assays. Moreover, pyrosequencing increased the specificity of the assays, up to 98-100%, while the sensitivity ranged between 32-63%. In summary, the mutation detection, especially in air-dried FNA samples, improves when using PCR assays in combination with high resolution melting analysis. Additional improvement can be obtained by subsequent pyrosequencing in comparison to previously described real-time PCRs using hybridization probes and fluorescence melting curve analysis.

2013 European thyroid association guidelines for cervical ultrasound scan and ultrasound-guided techniques in the postoperative management of patients with thyroid cancer.

Cervical ultrasound scanning (US) is considered a key examination, by all major thyroid and endocrine specialist societies for the postoperative follow-up of thyroid cancer patients to assess the risk of recurrence. Neck US imaging is readily available, non-invasive, relatively easy to perform, cost-effective, and can guide diagnostic and therapeutic procedures with low complication rates. Its main shortcoming is its operator-dependency. Because of the pivotal role of US in the care of thyroid cancer patients, the European Thyroid Association convened a panel of international experts to review technical aspects, indications, results, and limitations of cervical US in the initial staging and follow-up of thyroid cancer patients. The main aim is to establish guidelines for both a cervical US scanning protocol and US-guided diagnostic and therapeutic procedures in patients with thyroid cancer. This report presents (1) standardization of the US scanning procedure, techniques of US-guided fine-needle aspiration, and reporting of findings; (2) definition of criteria for classification of malignancy risk based on cervical US imaging characteristics of neck masses and lymph nodes; (3) indications for US-guided fine-needle aspiration and for biological in situ assessments; (4) proposal of an algorithm for the follow-up of thyroid cancer patients based on risk stratification following histopathological and cervical US findings, and (5) discussion of the potential use of US-guided localization and ablation techniques for locoregional thyroid metastases.

Thyroid cancer in patients with hyperthyroidism.

Thyroid cancer can be associated with thyrotoxicosis caused by Graves' disease, toxic multinodular goiter, or autonomously functioning thyroid adenoma. The objective of this study was to summarize current evidence regarding the association of thyroid cancer and hyperthyroidism, particularly with respect to the type of hyperthyroidism found in some patients, and whether this affects the outcome of the patient. A PubMed search was performed up to August 2011. Articles were identified using combinations of the following keywords/phrases: thyroid cancer, papillary thyroid cancer, follicular thyroid cancer, medullary thyroid cancer, anaplastic thyroid cancer, hyperthyroidism, Graves' disease, auto-nomous adenoma, toxic thyroid nodule, and toxic multinodular goiter. Original research papers, case reports, and review articles were included. We concluded that the incidence, as well as the prognosis of thyroid cancer associated with hyperthyroidism is a matter of debate. It seems that Graves' disease is associated with larger, multifocal, and potentially more aggressive thyroid cancer than single hot nodules or multinodular toxic goiter. Patients with Graves' and thyroid nodules are at higher risk to develop thyroid cancer compared to patients with diffuse goiter. Every suspicious nodule associated with hyperthyroidism should be evaluated carefully.

Anticancer metallotherapeutics in preclinical development.

This article reviews recent studies of platinum and other metal-containing antitumor drugs in preclinical development. A short overview of the development of cisplatin-based drug generations is given. Some pioneering strategies towards unconventional drugs, such as platinum complexes with biomolecules and carrier ligands, organoplatinum and multinuclear platinum complexes developed in recent years are outlined. Furthermore, nonplatinum-based antitumor drugs containing ruthenium(II/III), gallium(III), titanium(IV) or tin(IV) that illustrate the prominent strategies are presented with an emphasis on recent developments. In addition, alternatives for water insoluble drugs will be discussed. A brief overview of development of nanodrug delivery systems and their potential as alternative cancerostatic carriers are discussed.

Reduction of thyroid nodule volume by levothyroxine and iodine alone and in combination: a randomized, placebo-controlled trial.

CONTEXT: Nodular goiter is common worldwide, but there is still debate over the medical treatment. OBJECTIVE: The objective of the study was the measurement of the effect of a treatment with (nonsuppressive) T(4), iodine, or a combination of both compared with placebo on volume of thyroid nodules and thyroid. DESIGN: This was a multicenter, randomized, double-blind trial in patients with nodular goiter in Germany [LISA (Levothyroxin und Iodid in der Strumatherapie Als Mono-oder Kombinationstherapie) trial]. SETTING: The study was conducted in outpatient clinics in university hospitals and regional hospitals and private practices. PARTICIPANTS: One thousand twenty-four consecutively screened and centrally randomized euthyroid patients aged 18-65 yr with one or more thyroid nodules (minimal diameter 10 mm) participated in the study. INTERVENTION: Intervention included placebo, iodine (I), T(4), or T(4)+I for 1 yr. T(4) doses were adapted for a TSH target range of 0.2-0.8 mU/liter. OUTCOME MEASURES: The primary end point was percent volume reduction of all nodules measured by ultrasound, and the main secondary end point was a change in goiter volume. RESULTS: Nodule volume reductions were -17.3% [95% confidence interval (CI) -24.8/-9.0%, P < 0.001] in the T(4)+I group, -7.3% (95% CI -15.0/+1.2%, P = 0.201) in the T(4) group, and -4.0% (95% CI -11.4/+4.2%, P = 0.328) in the I group as compared with placebo. In direct comparison, the T(4)+I therapy was significantly superior to T(4) (P = 0.018) or I (P = 0.003). Thyroid volume reductions were -7.9% (95% CI -11.8/-3.9%, P < 0.001), -5.2% (95% CI -8.7/-1.6%, P = 0.024) and -2.5% (95% CI -6.2/+1.4%, P = 0.207), respectively. The T(4)+I therapy was significantly superior to I (P = 0.034) but not to T(4) (P = 0.190). CONCLUSION: In a region with a sufficient iodine supply, a 1-yr therapy with a combination of I and T(4) with incomplete suppression of thyrotropin reduced thyroid nodule volume further than either component alone or placebo.

High prevalence of TSHR/Gsα mutation-negative clonal hot thyroid nodules (HNs) in a Turkish cohort.

Whereas the majority of hot thyroid nodules are caused by somatic TSH-receptor mutations, the percentage of TSH-receptor mutation negative clonal hot nodules (HN) and thus the percentage of hot nodules likely caused by other somatic mutations are still debated. This is especially the case for toxic multinodular goiter (TMNG). 35 HNs [12 solitary hot nodules (SHN), 23 TMNG] were screened for somatic TSHR mutations in the exons 9 and 10 and for Gsα mutations in the exons 7 and 8 using DGGE. Determination of X-chromosome inactivation was used for clonality analysis. Overall TSHR mutations were detected in 14 out of 35 (40%) HNs. A nonrandom X-chromosome inactivation pattern was detected in 18 out of 25 (72%) HNs suggesting a clonal origin. Of 15 TSHR or Gsα mutation negative cases 13 (86.6%) showed nonrandom X-chromosome inactivation, indicating clonal origin. The frequency of activating TSHR and/or Gsα mutations was higher in SHNs (9 of 12) than in TMNGs (6 of 23). There was no significant difference for the incidence of clonality for HNs between TMNGs or SHNs (p: 0.6396). Activating TSHR and/or Gsα mutations were more frequent in SHNs than in TMNG. However, the frequency of clonality is similar for SHN and TMNG and there is no significant difference for the presence or absence of TSHR and/or Gsα mutations of clonal or polyclonal HNs. The high percentage of clonal mutation-negative HNs in SHN and TMNG suggests alternative molecular aberrations leading to the development of TSHR mutation negative nodules.

Nodulogenesis and goitrogenesis.

Goitrogenisis is the consequence of a relative iodine deficiency interacting with a genetic predisposition for maladaptation to iodine deficiency. In the long run, the iodine deficiency induces increased H2O2 production that leads to an increased mutagenesis, resulting in somatic mutations with a proliferative advantage and thus the induction of thyroid nodules.

Evidence for a more pronounced effect of genetic predisposition than environmental factors on goitrogenesis by a case control study in an area with low normal iodine supply.

Family and twin studies suggest a genetic predisposition for euthyroid goiters. However, iodine deficiency and smoking are important exogenous factors for goiter development. We investigated goiter predisposition by a matched case control study in a region with recently documented low normal iodine supply. A sum of 376 patients were included in the study. We matched 188 patients with euthyroid/subclinically hyperthyroid goiter (TSH 4.20-0.05 mU/l) with 188 euthyroid controls without thyroid enlargement for age and gender. Thyroid ultrasound was performed in all patients, whereby 50.5% of patients with goiters showed a positive family history for goiter. In contrast, only 25% of control patients had a positive family history (p<0.001; OR=3.1). Patients with goiters had a significantly higher proportion of parents (p<0.001; OR=3.6) or siblings (p=0.004; OR=2.5) with goiters. Children of parents with goiters showed a 2.7-fold increased risk for goiter development (goiter prevalence 73.3%). Patients with a positive goiter family history had a 4.1-fold increased goiter risk (p<0.001). The contribution of smoking, obesity, and pregnancies to goiter development was less important than the genetic predisposition (OR=1.7; p=0.06; OR=1.67; p=0.13; OR=0.8; p=0.56). In a region with low normal iodine supply, the significantly higher rate of positive family histories in patients with goiters as compared to the matched controls as well as the increased goiter prevalence in children of parents with goiters indicate the importance of genetic factors in goiter development.

American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and European Thyroid Association medical guidelines for clinical practice for the diagnosis and management of thyroid nodules.

American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and European Thyroid Association medical guidelines for clinical practice for the diagnosis and management of thyroid nodules are systematically developed statements to assist health care professionals in medical decision making for specific clinical conditions. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment was applied. These guidelines are a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with their best clinical judgment. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances.