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Mortar is of fundamental importance for the building technology. It is used to bind together masonry units and ease the building process. Several building techniques evolved to take advantage of the capacity of mortars to improve cohesiveness and form sound structures. In this paper, I discuss how lime and gypsum mortars were employed from the Antiquity to the Middle Ages. Gypsum mortars offered several advantages due to their adhesive properties and quick setting. Their use as a structural binding agent developed in regions rich in gypsum, and was particularly significant in vault construction. Lime mortars offered different advantages over gypsum ones, particularly in terms of mechanical resistance and resilience to humid conditions. The massive use of lime mortars started with the ancient Romans and continued throughout the centuries as the foremost binding material, until the introduction of Portland cement mortars in the nineteenth century. [ABSTRACT FROM AUTHOR]

The article discusses the topographic and urban elements of the area of Casa Bianca in the Sibari archeological excavations in Italy. Topics discussed include elaboration of structures existing in the eastern sector of Casa Bianca, the scope and variety of architectural elements, combining Roman and more recent styles; and architectural elements of buildings found in the western sector of Casa Bianca, also including a variety of styles. The article includes archeological images of the excavation sites.

The article discusses the conservation and restoration of the Sibari archeological site in Italy, with a focus on the reintegration and comprehensibility of the materials and structures found in the site. Topics discussed include the efforts of archeologists to construct and develop the cultural meaning and promote the cultural value of the findings at the Sibari site, the difficulty of reconstructing the forms and usage of the site during its history, and the efforts toward restoration of the site.

The article discusses the architecture of the Casa Bianca area in the archeological excavation of Sibari, in Italy, with a focus on the sanctuary and the first stages of the architectural description and restoration of the sanctuary. Topics discussed include the work of the Italian Archaeological School of Athens (SAIA) in the Casa Bianca area, including the history of excavations; description of the buildings included in the Casa Bianca and sanctuary area, and the precise layout of the area, including archeological diagrams.

The text is a collection of notes on the concept of minimum intervention in archaeological restorations. These are observations made during research and professional activities in which the principle of minimum intervention in relation to the various problems that have to be dealt with in order to slow down deterioration, to enhance the evocative capacity of the ruin, to restore the conditions of equilibrium through interventions of structural character and in case that reuse of the monument is forseen. In all these cases the minimum intervention does not always coincide with the minimum transfer of material. The professional has to identify, through his sensibility and capacity for understanding the reality of the artifact, the most appropriate solution in order to guarantee the necessary preconditions for passing on the work in its most authentic material and iconographic state. [ABSTRACT FROM AUTHOR]

No building of the Roman age can be compared to the large hall in the monumental complex known as "A Thermae", which lies between the theater and the agora of Argos. An analysis of the building system of the vault shows the architect and the workers' mastery of Roman building systems, as well as techniques of Oriental origin never attested in Rome. More specifically, the use of walls of regular courses of brick is Roman, as is that of opus caementicium, employed here to create slanted ceilings supporting the pitched roof. The building system of the vault, instead, employing side-by-side arches of trapeze-shaped bricks, is of Oriental origin. The presence of a cavity between the brick vault and the covering slabs, however, is the real architectural singularity of the building, where stability is achieved through masterful sizing and arranging of the various parts. [ABSTRACT FROM AUTHOR]

BACKGROUND Graves' disease and destruction-induced thyrotoxicosis can be discriminated on the basis of radioiodine uptake (RAIU); however, this test is contraindicated during lactation. In addition, not all institutions have the facilities to assess this parameter. OBJECTIVE To evaluate whether measurement of thyroid blood flow can be used to differentiate between Graves' disease and destruction-induced thyrotoxicosis. DESIGN AND INTERVENTION This Japanese study evaluated patients aged 14-70 years who had untreated thyrotoxicosis. A control group of healthy individuals was also assessed. Levels of serum TSH, free T4 and free T3 levels were measured by chemiluminescent immunoassay. Serum anti-TSH-receptor antibody ('TSH-binding inhibitory immunoglobulin'; TBII) levels were measured by enzyme-linked immunosorbent assay and the results were expressed as the percent inhibition of TSH binding, with a cut-off value of <15%.Thyroid volume and blood flow were measured by Doppler ultrasonography. RAIU was measured at 3 h and 24 h. Graves' disease was diagnosed in patients with elevated free T4 and free T3 levels, reduced TSH levels, high TBII levels, and/or high RAIU. Painless thyroiditis was diagnosed in the presence of elevated free T4 and free T3 levels for <3 months, and/or development of transient hypothyroidism, and/or low RAIU. Subacute thyroiditis was diagnosed in patients with fever, neck pain or swelling, in the presence of elevated free T4 and free T3 levels, low thyroid gland echogenity, and/or low RAIU. OUTCOME MEASURES The main outcome measures were thyroid blood flow, thyroid volume, TBII status, and RAIU. RESULTS The study assessed 56 patients with Graves' disease (mean age 41.3 years), 28 patients with painless thyroiditis (mean age 40.9 years), 30 patients with subacute thyroiditis (mean age 50.0 years), and 25 healthy controls (mean age 38.7 years). Thyroid volume was greater in patients with thyroiditis than in healthy controls (P<0.0001); however, there was no significant difference in this parameter between the thyroiditis groups. Thyroid blood flow, TBII levels, and RAIU were higher in patients with Graves' disease than in those with destruction-induced thyrotoxicosis (P<0.0001). Patients with Graves' disease had a thyroid blood flow >4%, whereas patients with destruction-induced thyrotoxicosis had a thyroid blood flow <4%. All 56 patients with Graves' disease had TBII levels >15%. High TBII levels were also detected in 3 patients with painless thyroiditis and 1 patient with subacute thyroiditis. Thyroid blood flow correlated with RAIU at 3 h (coefficient of correlation [r] = 0.492; P <0.01) and 24h (r=0.762; P<0.001) in patients with Graves' disease and painless thyroiditis. There was no correlation, however, between thyroid blood flow and either thyroid volume or TBII level in patients with Graves' disease. CONCLUSION Thyroid blood flow >4% differentiated Graves' disease from destruction-induced thyrotoxicosis and was a reliable alternative to RAIU. [ABSTRACT FROM AUTHOR]

The relevance of thyroid autoimmunity to the prognosis of papillary thyroid carcinoma is still unsettled. We decided to investigate the impact of thyroid autoimmunity on the prognosis of papillary thyroid carcinoma and the handling of TgAbs. We evaluated the clinical course of a large group of patients according to the presence (PTC-LT) or absence (PTC) of lymphocytic thyroiditis at histology. We studied 194 consecutive patients with a diagnosis of PTC and treated them with total thyroidectomy plus 131I ablation between 2007 and 2009. Median follow-up (with 25th-75th percentiles) was 84.0 (56.4-118.0) months. The remission criteria were: basal Tg < 0.2 ng/mL (or stimulated Tg: < 1), TgAbs < 8 IU/mL (otherwise 'decreasing TgAb trend', a decline of ≤20% in sequential TgAb measurements) and unremarkable imaging. PTC-LT and PTC patients had comparable treatment. TgAbs were detectable in 72.5% of PTC-LT and 16.5% of PTC patients. Time to remission was longer in the detectable than in the undetectable TgAb cohort (28.5 vs· 7.5 months (median); HR: 0.54, CI: 0.35-0.83, P = 0.005). When comparing PTC-LT to PTC patients, the difference was maintained in the detectable TgAb (29.3 vs 13.0 months; HR: 0.38, CI: 0.18-0.80; P = 0.01) but not in the undetectable TgAb cohort (7.7 vs 7.3 months; HR: 0.90, CI: 0.55-1.47; P = 0.68). Using the decreasing TgAb trend, the influence of detectable TgAbs on time to remission was abolished. Thyroid autoimmunity does not influence the prognosis of papillary thyroid carcinoma. A decreasing TgAb trend seems an appropriate criterion to establish the remission of papillary thyroid carcinoma. [ABSTRACT FROM AUTHOR]

Background Using recombinant human monoclonal thyroglobulin antibodies expressed as Fab molecules (TgAb-Fab), we have recently confirmed the restriction of Tg epitopes in Hashimoto’s thyroiditis (HT). Objective To investigate Tg epitopes of serum TgAb in HT adults and HT juveniles from a geographically isolated area (Sardinia). Design and Patients Serum TgAb of 39 Sardinian HT adults, 53 Sardinian HT juveniles and 45 non-Sardinian HT adults were evaluated. The binding of serum TgAb to Tg in ELISA was inhibited by four recombinant human TgAb-Fab, identifying Tg epitopic regions A–D. The percentage of Tg binding inhibition was calculated comparing the binding of serum TgAb in presence of each TgAb-Fab with that in its absence. Results In the whole cohort of 137 patients, A region TgAb-Fab induced the highest levels of inhibition (55·3 ± 17·8%) (mean ± SD). Lower levels of inhibition were induced by TgAb-Fab of regions B (27·8 ± 25·8%), C (26·8 ± 24·6%) and D (17·5 ± 18·4%). In Sardinian HT adults inhibition by TgAb-Fab of regions A, B and C were comparable to Sardinian HT juveniles; the marginal D region TgAb-Fab induced a slightly higher inhibition (22·1 vs. 13·8%; P = 0·034) in the former than in the latter group. In Sardinian and non-Sardinian HT adults inhibitions by the four TgAb-Fab were similar. Conclusions In HT, the Tg epitope pattern of serum TgAb was similar in juveniles and adults from a geographically restricted area and in two adult populations from different geographical areas. Thus, in HT, neither age nor genetic background appear to influence B-cell epitopes. [ABSTRACT FROM AUTHOR]

To investigate the risk of hypothyroidism after radioiodine (131I) treatment for hyperfunctioning thyroid nodules.Retrospective analysis of patients treated with131I for hyperfunctioning thyroid nodules and followed up for a maximum of 20 years.A total of 346 patients treated with131I in the years 1975–95, for a single hyperfunctioning nodule.Hypothyroidism was defined as TSH levels> 3·7 mU/l. Kaplan–Meier survival analysis was used to analyse permanence of euthyroidism after131I. A stepwise Cox proportional hazard model was used to identify factors influencing the progression to hypothyroidism.The cumulative incidence of hypothyroidism was 7·6% at 1 year, 28% at 5 years, 46% at 10 years and 60% at 20 years. Age (P < 0·01), 24-th131I uptake (P < 0·05) and previous treatment with methimazole (MMI,P < 0·1) were associated with a faster progression towards hypothyroidism, while thyroid and nodule size, thyroid status at diagnosis and degree of extranodular thyroid parenchymal suppression had no influence. In hyperthyroid patients with partial parenchymal suppression, however, previous MMI treatment was the most important prognostic factor (P < 0·01).After 20 years of follow-up, 60% of patients treated with131I for a single hyperfunctioning nodule are hypothyroid. Factors increasing the risk of hypothyroidism are age,131I uptake and MMI pretreatment. The prognostic value of this last factor, however, depends on the degree of suppression of the extranodular thyroid parenchyma at the scan. [ABSTRACT FROM AUTHOR]

Objective: Recently, several scientific societies designed ultrasound (US) risk stratification systems (RSS) to guide the workup of thyroid nodules and decide which nodules should under go fine-needle aspiration cytology (FNAC). However, these systems have been developed against papillary thyroid car cinoma, and scanty data on their role in identifying medullary thyroid carcinoma (MTC) are available. The aims of this study are to describe the US features of MTC and evaluate the performance of RSS in identifying MTC. Methods: Data of 152 consecutive patients with MTC was evaluated. The re sults of the pre-operative neck US of all patients were collected. Ultrasound features of each MTC were e valuated and classified according to the five main RSS available. Results: Median MTC dimension was 1.3 cm. Most of the nodules showed so lid composition, hypoechoic pattern, and regular margins. About half of them showed the presence of calcifications, but only a subgroup had microcalcifications. A minority of the nodules showed a 'taller than wide' shape. Only 7.9% of all MTC showed the simultaneous presence of at least four US features suggestive of malignancy. Ultrasonographic high-risk of malignancy of the MTC included in the five RSS, varied from 45.4 to 47.4%, and performing FNAC was suggested in only 48.7 to 63.8% of all MTC. Conclusions: In this series, neither single nor the association of US featu res are specific for MTC. The five main RSS correctly identify less than 50% of MTC and do not suggest perf orming FNAC in about half of them with potentially missed or delayed diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: We report on a 36-year-old infertile woman, presenting a premature ovarian failure with an otherwise normal female phenotype. Cytogenetic analyses showed the presence of a supernumerary marker chromosome, that was characterized by FISH (fluorescent in situ hybridization) and array CGH (comparative genomic hybridization). This marker chromosome was derived from chromosome 15, and contained only heterochromatic material. The Prader Willi/Angelman region was not present. No duplications of the 15q regions were detected by array CGH. Supernumerary markers of chromosome 15 have been reported in cases of infertility and amenorrhea, that is also described in cases with marker derived by other acrocentric chromosomes. The case here presented constitutes a further example that etiology of POF is not always associated with a defective gene, but in some cases oocytes atresia can be the consequence of the abnormal meiotic pairing of chromosomes. [Copyright &y& Elsevier]

Background. The tyrosine kinase inhibitors (TKIs) are indicated for the treatment of locally advanced or metastatic progressive thyroid carcinoma (CDT), refractory to radioactive iodine. The following report describes the efficacy of lenvatinib administered through a nose-gastric tube (SNG) in a patient affected with a poorly differentiated thyroid carcinoma (PDTC) which determined a stenosis of the esophagus. Material and Methods. A patient was followed up for papillary thyroid carcinoma follicular variant (T3NxMx), subjected to total thyroidectomy and treated with iodine-131 radio metabolic therapy. Two years after surgery, following the onset of dysphonia and dysphagia, patient was submitted to a computed tomography (CT) scan of the neck that showed the presence of a lesion of 6 × 2.5 × 3.5 cm, which determined trachea deviation and cervical esophagus compression. The biopsy indicated the presence of PDTC, triggering tracheal lumen reduction and sub-stenosis of the cervical esophagus for an ab-extrinsic compression. A nose-gastric tube (SNG) was placed and lenvatinib was started at a dose of 20 mg/day, administered via this probe after opening the capsules and diluting the drug in 10 ml of saline solution. Results. One month later, CT showed a significant cervical lesion reduction. Bronchoscopy confirmed tracheal infiltration, but the residual caliber was improved from 50% to 75%. At the esophagogastroduodenoscopy (EGDS), the sub stenosis of the cervical esophagus was no longer appreciated; however, a double perforation of the esophagus was found, without fistula. Conclusion. Lenvatinib therapy is effective also when administered via SNG. Our result is of particular relevance in the management of thyroid cancer patients, especially in the presence of subjects unable to swallow. Further studies are needed to validate the administration of lenvatinib by SNG, in order to extend the indications to this alternative administration way, beside the oral one. [ABSTRACT FROM AUTHOR]

Summary: Objective: To compare the efficacy of Radioiodine (RI) and Radiofrequency ablation (RFA) in the treatment of autonomously functioning thyroid nodules (AFTNs). End‐points: nodule volume reduction (NVR) and thyroid function normalization. Design, patients and measurements: Twenty‐two patients (2:20 M:F; 51.9 ± 13.9 years) affected by 25 AFTNs, treated by RFA were retrospectively compared with 25 patients (8:17 M:F; 57.2 ± 12.8 years) affected by a single AFTN treated by RI. Both group showed analogous characteristics as to age, gender, toxic/pretoxic phase and pretreatment nodule volume (calculated by the ellipsoid formula). Thyroid hormone levels and autoimmune thyroid profile were assessed before treatment. A fixed RI activity of 555 MBq (15 mCi) was administered. RFA was performed with an 18G, single‐tipped electrode, by the "modified moving shot technique." Thyroid hormones were assessed and the nodule post‐treatment volume calculated 12 months after treatment. Results: No statistical difference was found between the post‐treatment NVR by comparing RI and RFA (P = 0.69). The volume reduction rates were 68.4 ± 28.9% and 76.4 ± 16.9% after RI and RFA, respectively. As to the thyroid function, 5/25 patients developed clinical hypothyroidism after RI. After RFA, all the 22 patients silenced their AFTN and normalized the thyroid hormones. Subclinical hypothyroidism was recorded in two patients after both RI and RFA. Thus, the functional therapeutic success, defined as the restoration of euthyroidism, was achieved in 18/25 (72%) patients treated by RI and in 20/22 (90.9%) treated by RFA. Conclusions: No statistical difference in NVR was found between RI and RFA. All patients responded to RI but 5/25 were "over‐treated" developing hypothyroidism. RFA was effective in all patients with no case of post‐treatment clinical hypothyroidism. No radiation exposure and lower risk of post‐treatment hypothyroidism might make RFA the favourite option especially for young patients. [ABSTRACT FROM AUTHOR]

Abstract Follicular Variant of Papillary Thyroid Carcinoma (FVPTC) is usually associated with a good outcome. Nevertheless, in rare cases, it develops distant metastases (1–9%). Our goal was to investigate whether mRNA and miRNA expression profiles may help distinguish between metastatic versus non-metastatic FVPTCs. Twenty-four primary FVPTCs, 12 metastatic and 12 non-metastatic, with similar clinicopathological features were selected and analyzed by nanoString nCounter technology using two distinct panels for expression analysis of 740 mRNA and 798 miRNAs. Data analysis was performed using the nanoString nSolver 3.0 software. Forty-seven mRNA and 35 miRNAs were differentially expressed between the two groups. Using these mRNA and miRNAs, metastatic and non-metastatic FVPTCs were clearly divided into two distinct clusters. Our results indicate that FVPTCs with metastatic abilities have different expression profiles compared to the non-metastatic. A prospective validation is needed to evaluate the usefulness of this molecular approach in the early identification of high-risk FVPTCs. Highlights • No molecular signatures are currently available for metastatic potential of FVPTCs. • A set of mRNA and miRNA are significantly deregulated in metastatic tumors. • A mRNA/miRNA signature could identify FVPTCs at risk to develop metastasis. [ABSTRACT FROM AUTHOR]

Background: The outcomes of patients with thyroid cancer proven by histology in patients in whom cytology was Thy 3 (indeterminate; Thy 3 patients in this study) based on the Italian consensus classification compared with those in whom cytology was Thy 4 (suspicious for malignancy) or Thy 5 (indicative for malignancy) (Thy 4–5 patients here) remains unclear. Objective: To analyze the outcome of 371 Thy 3 patients versus 269 Thy 4–5 patients homogeneously treated with total thyroidectomy and 131I activity. Results: T1 stage was observed in 46.0% of Thy 3 and in 38.8% of Thy 4–5 patients (p = 0.02), N0 in 95.9% of Thy 3 and in 75.5% of Thy 4–5 patients (p < 0.0001). 35/261 (9.6%) Thy 3 and 85/269 (31.5%) Thy 4–5 patients required >30 mCi of 131I (p < 0.0001). 359/371 (96.8%) Thy 3 and 232/269 (86.2%) Thy 4–5 patients were free of disease at the end of follow-up (p < 0.001). The time required to obtain 50% of patients in remission was 2 years in Thy 3 and 4 years in Thy 4–5 patients (p < 0.001). The most common histological type was the follicular variant of papillary thyroid carcinoma (FV-PTC) in Thy 3 patients (239/371, 64.4%) and the classic variant in Thy 4–5 patients (185/269; 68.8%). The FV-PTC had better prognostic features compared with the other PTC variants: T1 stage was observed in 133/277 (48.0%) FV-PTC patients and in 146/363 (40.0%) patients with the other variants (p < 0.001), N0 was present in 265/277 (96.0%) FV-PTC and in 290/363 (79.8%) patients with the other variants (p < 0.001). Overall, 267/277 FV-PTC patients (96.4%) and 324/363 patients (89.0%) with the other variants were free of disease (p < 0.0008) at the end of follow-up, and the time required to obtain 50% of patients in remission was 2 years in FV-PTC and 4.0 years in the other variants (p < 0.001). Conclusion: Patients with Thy 3 cytology have better outcomes of thyroid cancer compared with patients with Thy 4 or Thy 5 cytology, and indeterminate cytology is commonly associated with the less aggressive FV-PTC. [ABSTRACT FROM AUTHOR]

Background: Thyroglobulin (Tg) antibodies (TgAb) can interfere with Tg measurement and can be used as “Tg surrogate” in patients with differentiated thyroid cancer (DTC) treated with total thyroidectomy (TTx) and radioiodine remnant ablation (RRA). In contrast, few data, and in patients usually followed for a short-term follow-up, have been reported about the changes of TgAb levels in patients treated with TTx but without RRA. The aims of this study were to evaluate the changes of TgAb levels in DTC patients treated with TTx but not RRA and to identify the factors that influence these changes. Methods: The change in TgAb levels in 107 DTC (<1 cm) patients submitted to TTx but not RRA was evaluated. Patients were followed for a median of 6.3 years, and all had at least three determinations of TgAb and neck ultrasound (nUS). Results: TgAb levels showed a progressive decrease during follow-up. Initial TgAb levels and degree of lymphocytic infiltration influenced the time but not the rate of TgAb disappearance. No influence on time and rate of the decrease in TgAb was observed when the association with thyroperoxidase antibodies (TPOAb) levels were considered. A TgAb cutoff value of 61.9 IU/mL at first postoperative evaluation was a good indicator for disappearance of the TgAb within six years. No tumor recurrence was observed in the series. In one case, the progressive increase in TgAb anticipated the reappearance of benign thyroid tissue with lymphocytic infiltration. Conclusions: TgAb levels decline in the majority of DTC patients treated with TTx but not ablated with radioiodine. The levels decrease rapidly after the surgical treatment and continue to decrease over time. The time of disappearance is influenced by the initial TgAb levels and the degree of lymphocytic infiltration. No influence of the actual TPOAb levels has been observed. An increase in TgAb levels should not be overlooked, since it can indicate the presence or reappearance of either normal thyroid tissue or tumor recurrence. [ABSTRACT FROM AUTHOR]

Anaplastic (ATC) and poorly differentiated thyroid cancer (PDTC) are very aggressive cancers whose histological diagnosis is not always straightforward. Clinical, pathological and genetic features may be useful to improve the identification of these rare histotypes. In the present study the clinical, pathological and genetic features of two groups of ATC (n=21) and PDTC (n=21) patients were analyzed. Clinical data were retrieved from a computerized database. The oncogenic profiles were studied using the Sanger sequencing method of a selected series of oncogenes and/or tumor suppressor genes known to be altered in these tumors. The presence of macrophages in both series of tissues was evaluated by immunohistochemistry. Patients with ATC were older and affected by a more advanced disease at diagnosis than those with PDTC. The median survival was significantly shorter in ATC compared with PDTC patients (P=0.0014). ATC showed a higher prevalence of TP53 and TERT mutations (10/21, 47.6% and 9/21, 42.8%, respectively) while TERT and BRAF mutations were the most prevalent in the PDTC group (7/21, 33.3% and 4/23, 19% respectively). Genetic heterogeneity (i.e., >2 mutations) was more frequent in ATC (10/21, 28.6%) compared with in PDTC (3/21, 4.7%) (P=0.03). Macrophages were more frequently present in ATC, particularly in those cases with TP53 mutations. In conclusion, these data indicate that ATC and PDTC may be characterized by different clinical, pathological and genetic profiles. In particular ATC, but not PDTC, were positive for TP53 and PTEN alterations. Complex mutations were also found in ATC but not in PDTC. Moreover, genetic heterogeneity was more frequent in ATC than PDTC. Finally, TP53 mutation and the accumulation of several mutations correlated with a shorter survival time. [ABSTRACT FROM AUTHOR]

The 2017 American Thyroid Association guidelines for the diagnosis and management of thyroid disease during pregnancy and the postpartum were published six years after the previous ones. They provide comprehensive clinical recommendations for the whole spectrum of thyroid diseases, as well as for optimal iodine intake during pregnancy, postpartum, and lactation. The present position statement mainly regards the recommended flow chart for therapeutic decision making in pregnant women being diagnosed with subclinical hypothyroidism. Here, we comment on the major biochemical and clinical situations and the corresponding therapeutic recommendations. In particular, we welcome the critical revision of the thyrotropin (TSH) reference range in pregnancy, and we agree that there is no need to treat thyroid peroxidase antibody–negative women with a serum TSH ranging from 2.5 μIU/mL to the upper limit of the reference range. This recommendation will hopefully reduce the huge proportion of healthy pregnant women in whom, according to the previous guidelines, levothyroxine therapy had to be initiated. On the other hand, we are concerned with the recommendation to only “consider treatment” in thyroid peroxidase antibody–negative pregnant women with a serum TSH ranging from the upper limit of the reference range to 10.0 μIU/mL. This is because thyroid antibodies may be falsely negative during gestation, and serum negative chronic autoimmune thyroiditis is a well-known clinical entity even outside pregnancy. Based on these and other arguments, we recommend treatment with levothyroxine in pregnant women with TSH levels ranging between the upper limit of the reference range and 10.0 μIU/mL independently from their thyroid antibody status. [ABSTRACT FROM AUTHOR]

Background: In order to establish whether thyroglobulin autoantibodies (TgAb) influence the metabolic clearance of thyroglobulin (Tg) in humans, serum Tg and TgAb were correlated shortly after radioiodine (131I) treatment. Methods: Samples were collected from 30 consecutive patients undergoing 131I activity for Graves' hyperthyroidism at the time of treatment and every 15 days thereafter, up to 90 days. Tg and TgAb were measured by immunometric assays (functional sensitivities: 0.1 ng/mL and 8 IU/mL). Results: Tg was detectable in all patients at day 0. Tg concentrations rose from a mean of 33.2 ng/mL [confidence interval (CI) 17.8-61.0 ng/mL] at day 0 to a mean of 214.6 ng/mL [CI 116.9-393.4 ng/mL] at day 30 and then steadily decreased, reaching the lowest concentration at day 90 (M= 10.9 ng/mL [CI 5.5-20.9 ng/mL]). Compared to their levels at day 0 (M= 23.6 IU/mL [CI 10.5-52.9 IU/mL]), TgAb remained stable through day 15 and then gradually increased up to a mean of 116.6 IU/mL [CI 51.9-262.2 IU/mL] at day 90. Patients were then split into two groups according to their TgAb status at day 0: undetectable (<8 IU/mL; 9 patients) or detectable (≥8 IU/mL; 21 patients) TgAb. Compared to the other cohort, patients with detectable TgAb showed significantly lower Tg concentrations at day 0 (M= 20.3 ng/mL [CI 10.1-40.2 ng/mL] vs. M= 101.8 ng/mL [CI 36.6-279.8 ng/mL]), similar at day 15, lower levels at day 30 (M= 146.5 ng/mL [CI 74.3-287.8 ng/mL] vs. M= 514.8 ng/mL [CI 187.8-1407.9 ng/mL]), at day 45 (M= 87.5 ng/mL [CI 43.1-176.6 ng/mL] vs. M= 337.9 ng/mL [CI 120.1-947.0 ng/mL]), at day 60 (M= 61.6 ng/mL [CI 31.0-121.4 ng/mL] vs. M= 255.8 ng/mL [CI 79.0-823.8 ng/mL]), and at day 75 (M= 24.5 ng/mL [CI 11.9-49.2 ng/mL] vs. M= 249.5 ng/mL [CI 63.5-971.1 ng/mL]), and similar levels at day 90. Patients with detectable TgAb showed a lower (M= 182.5 ng/mL [CI 92.0-361.0 ng/mL] vs. M= 514.8 ng/mL [CI 187.8-1407.9 ng/mL]) and an earlier (day 15 vs. day 30) peak of Tg. The mean Tg concentration was lower in patients with detectable TgAb than in those with undetectable TgAb (area under the curve: 17,340 ± 16,481 ng/mL vs. 36,883 ± 44,625 ng/mL; p = 0.02). Conclusions: TgAb influence the changes in Tg concentrations observed immediately after 131I treatment, inducing lower levels and an earlier peak of Tg. These observations indicate that TgAb significantly influence the metabolic clearance of Tg, supporting the concept that their interference in the measurement of Tg is mainly due to an in vivo effect. [ABSTRACT FROM AUTHOR]

Background: Limited data suggest that treatment with statins is associated with a reduced risk of Graves' orbitopathy (GO) in patients with Graves' disease (GD), attributed to the anti-inflammatory rather than to the hypolipemic effects of these medications. The aim of the present study was to investigate whether there is an association between high cholesterol and GO. The primary outcome was the relation between GO and lowdensity lipoprotein (LDL)-cholesterol. The secondary outcomes were the relation between severity or activity (the clinical activity score [CAS]) of GO and LDL-cholesterol. Methods: A cross-sectional investigation was conducted in consecutive patients with GD who came under the authors' observation to undergo radioiodine treatment, a stratification aimed at forming two distinct groups of patients under the same conditions. A total of 250 patients were enrolled, 133 with and 117 without GO. Ophthalmological assessments and serum lipids measurements were performed. Results: In multivariate analyses with correction for the duration of hyperthyroidism, a variable that differed between patients with respect to the presence or absence of GO, a correlation between the presence of GO and both total (p = 0.01) and LDL-cholesterol (p = 0.02) was observed. In patients with hyperthyroidism lasting <44 months, total and LDL-cholesterol were higher (p = 0.01 and p = 0.008, respectively) among GO patients. In this subgroup, based on the presence/absence of GO, cutoff values were established for total (191 mg/dL) and LDL-cholesterol (118.4mg/dL), above which an increased risk of GO was observed (total cholesterol relative risk: 1.47; p = 0.03; LDL-cholesterol relative risk: 1.28; p = 0.03). GO severity and CAS did not correlate with serum lipids. However, CAS was found to be higher (p = 0.02) in patients with high total cholesterol. When the analysis was restricted to untreated GO patients, a correlation was found between CAS and both total (p = 0.04) and LDL-cholesterol (p = 0.03), after adjustment for GO duration. Conclusions: In patients with a short duration of hyperthyroidism, total and LDL-cholesterol correlate with the presence of GO, suggesting a role of cholesterol in the development of GO. Depending on GO duration, total and LDL-cholesterol correlate with GO activity, suggesting a role of cholesterol in the clinical expression of GO. [ABSTRACT FROM AUTHOR]

Papillary thyroid carcinoma (PTC) is the most common type of endocrine malignancy and accounts for ~80% of thyroid carcinomas in adults and 90% in children. Risk stratification is important for identifying patients at higher risk and, for this reason, recent advances in molecular genetics of thyroid cancer can be applied to provide novel biomarkers useful in understanding tumor behavior. B‑Raf proto‑oncogene, serine/threonine kinase (BRAF) and rat sarcoma (RAS) mutations have been widely studied and appear to have an important role in thyroid tumorigenesis. Somatic telomerase reverse transcriptase (TERT) promoter mutations have been recently identified in several types of malignant tumors, including thyroid neoplasia; however, the actual role of TERT mutations in thyroid tumorigenesis is still under debate. In the present study, the mutational status of BRAF, RAS and TERT was analyzed in order to elucidate the roles of these genes in thyroid tumorigenesis. The TERT mutational analysis was also correlated with an immunohistochemical study of TERT protein expression. According to the literature, our data provide evidence of the BRAF and RAS roles in thyroid tumorigenesis, supporting an association between BRAF (V600E) mutations and the more aggressive clinical and pathological features of thyroid tumors. By contrast, TERT mutations were not significantly associated with any clinical parameters; therefore, its role in initial tumorigenesis should be further investigated. [ABSTRACT FROM AUTHOR]

Absence of neoplastic disease in the organ-recipient is required in order to allow organ transplantation. Due to its rarity, no data regarding management of patients with Multiple endocrine neoplasia type 1 (MEN1) and end-stage renal failure candidates for kidney transplantation are available. A 36 year-old man was referred to the present hospital with MEN1, with a neuroendocrine pancreatic tumor and primary hyperparathyroidism and associated Alport syndrome with end stage renal failure. The present study aimed to establish the eligibility of the patient for a kidney transplantation. The neuroendocrine tumor had been treated with duodenopancreatectomy two years earlier and hyperparathyroidism by parathyroidectomy. The review of the literature did not provide data regarding the eligibility for kidney transplantation of patients harboring a neuroendocrine pancreatic tumor in the context of MEN1. Due to the end-stage renal failure, neuroendocrine markers were unreliable and the investigation therefore relied on imaging studies, which were unremarkable. Young age, low-grade tumor, low expression of Ki67, absence of metastatic lymph nodes, onset in the setting of a MEN1 were all positive prognostic factors of the neuroendocrine tumor. Normal serum calcium ruled out persistent primary hyperparathyroidism. Overall, hemodyalisis is known to significantly reduce life expectancy. Benefits of kidney transplantation overcome the risk of neuroendocrine tumor recurrence in a young patient bearing MEN1. [ABSTRACT FROM AUTHOR]

Anaplastic thyroid carcinoma (ATC) is a rare malignancy, accounting for 1-2% of all thyroid cancers. Although rare, ATC accounts for the majority of deaths from thyroid carcinoma. ATC often originates in a pre-existing thyroid cancer lesion, as suggested by the simultaneous presence of areas of differentiated or poorly differentiated thyroid carcinoma. ATC is characterized by the accumulation of several oncogenic alterations, and studies have shown that an increased number of oncogenic alterations equates to an increased level of dedifferentiation and aggressiveness. The clinical management of ATC requires a multidisciplinary approach; according to recent American Thyroid Association guidelines, surgery, radiotherapy and/or chemotherapy should be considered. In addition to conventional therapies, novel molecular targeted therapies are the most promising emerging treatment modalities. These drugs are often multiple receptor tyrosine kinase inhibitors, several of which have been tested in clinical trials with encouraging results so far. Accordingly, clinical trials are ongoing to evaluate the safety, efficacy and effectiveness of these new agents. This Review describes the updated clinical and pathological features of ATC and provides insight into the molecular biology of this disease. The most recent literature regarding conventional, newly available and future therapies for ATC is also discussed. [ABSTRACT FROM AUTHOR]

Background: The follicular variant (FV) of papillary thyroid cancer (PTC) is one of the most common variants of PTC. Clinically, non-infiltrative FVPTC is considered a low-risk variant of PTC, and the non-invasive encapsulated forms of FVPTC represent a group of thyroid tumors with a particularly good prognosis. Consequently, these neoplasms have been very recently reclassified as non-invasive follicular neoplasms with papillary-like nuclear features (NIFTP). From a molecular standpoint, NIFTP appears to be similar to follicular neoplasms. However, only limited data are currently available regarding their gene expression profile. Methods: The aim of this study was to identify specific molecular signatures of 26 NIFTPs compared to those of 19 follicular adenomas (FAs) and 18 infiltrative FVPTCs (IFVPTCs). A nanoString custom assay was used to perform mRNA expression analysis. All cases were also genotyped for BRAF, N-, H-, and K-RAS mutations. Samples were grouped on the basis of gene expression profiles by Pearson's correlation and non-negative matrix factorization clustering analysis. Finally, the uncorrelated shrunken centroid machine-learning algorithm was used to classify the samples. Results: The results revealed distinct expression profiles of FAs and IFVPTCs. NIFTP samples can exhibit different expression profiles, more similar to FAs (FA-like) or to IFVPTCs (IFVPTC-like), and these different expression profiles largely depend on the presence of different mutations ( RAS or BRAF). Conclusion: In conclusion, although further validation of the model is required by using a larger group of prospective cases, these data reinforce the hypothesis that IFVPTC-like NIFTPs might represent precursors of IFVPTC. [ABSTRACT FROM AUTHOR]

Noninvasive encapsulated follicular variants of papillary thyroid carcinomas have been recently reclassified as noninvasive follicular thyroid neoplasms with papillarylike nuclear features (NIFTPs). NIFTPs exhibit a behavior that is very close to that of follicular adenomas but different from the infiltrative and invasive follicular variants of papillary thyroid carcinomas (FVPTCs). The importance of miRNAs to carcinogenesis has been reported in recent years. miRNAs seem to be promising diagnostic and prognostic molecular markers for thyroid cancer, and the combination of miRNA expression and mutational status might improve cytological diagnosis. The aim of the present study was to evaluate the miRNA expression profile in wild-type, RAS- or BRAF-mutated NIFTPs, infiltrative and invasive FVPTCs, and follicular adenomas using the nCounter miRNA Expression assay (NanoString Technologies). To identify the significant Kyoto Encyclopedia of Genes and Genomes (KEGG) molecular pathways associated with deregulated miRNAs, we used the union of pathways option in DNA Intelligent Analysis (DIANA) miRPath software. We have shown that the miRNA expression profiles of wildtype and mutated NIFTPs could be different. The expression profile of wild-type NIFTPs seems comparable to that of follicular adenomas, whereas mutated NIFTPs have an expression profile similar to that of infiltrative and invasive FVPTCs. The upregulation of 4 miRNAs (miR-221-5p, miR-221-3p, miR-222-3p, miR-146b-5p) and the downregulation of 8 miRNAs (miR-181a-3p, miR-28-5p, miR-363-3p, miR-342-3p, miR-1285-5p, miR-152-3p, miR-25-3p, miR-30e-3) in mutated NIFTPs compared to wild-type ones suggest a potential invasive-like phenotype by deregulating the specific pathways involved in cell adhesion and cell migration (Hippo signaling pathway, ECM-receptor interaction, adherens junction, regulation of actin cytoskeleton, fatty acid biosynthesis and metabolism). [ABSTRACT FROM AUTHOR]

BRAF mutations represent the most common genetic alteration in papillary thyroid carcinoma (PTC). The p.V600E mutation is specific for the classic and tall-cell variants of PTC and has been associated with a more aggressive biologic behavior. On the other hand, the p.K601E mutation is peculiar to the follicular variant of PTC, and seems to be a favorable prognostic indicator. A 12-year-old boy presented with a 10-mm left-sided thyroid nodule. Fine-needle aspiration cytology reported the lesion as suspicious for a follicular neoplasm (Bethesda category IV). The patient underwent lobectomy, and histopathology revealed a follicular adenoma with normal surrounding tissue. The cytological smear was found to be positive for BRAF p.K601E mutation, and this was later confirmed on the corresponding paraffin block. This case was independently revised by 4 expert pathologists, all of whom confirmed the benign nature of the thyroid lesion. This article describes the presence of a BRAF mutation in a benign thyroid lesion. To the authors' knowledge, this is the fourth case of follicular adenoma carrying BRAFK601E reported in literature to date. BRAFK601E mutation can occur in benign thyroid lesions. This finding, in the context of the current literature and the recently proposed reclassification of the noninvasive encapsulated follicular variant of papillary thyroid carcinoma into a benign lesion, confirms the importance of preoperative BRAF p.K601E testing in offering patients a tailored treatment plan and avoiding overtreatment. [ABSTRACT FROM AUTHOR]

Introduction Italy is still characterized by a mild iodine deficiency and is among the most intensive users of chemical products for agriculture in Europe. The aim of this study was i) to evaluate thyroid effects of exposure to mancozeb, a fungicide widely used in agriculture, in a sample of Italian grapevine workers, and ii) to verify whether the iodine intake may modulate the risk of thyroid disruption due to the mancozeb metabolite ethylenthiourea (ETU). Methods One hundred seventy-seven occupationally exposed male workers (29 from Chianti, a mild iodine deficient area, and 148 from Bolzano an iodine sufficient province) and 74 non-occupationally exposed male controls (34 from Chianti and 40 from Bolzano) were enrolled in the study. Serum biomarkers of thyroid function, as well as urinary iodine and ETU concentrations were assessed. Moreover all the recruited subjects underwent clinical examination and thyroid ultrasound. Results Multivariate comparisons showed lower mean serum levels of FT4 in Chianti-workers as compared to Bolzano-workers. Moreover, an increased urinary iodine excretion (>250 µg/L) was more frequently found among more exposed workers (ETU>20 µg/L) than among less exposed ones and this effect was more pronounced in Chianti- than in Bolzano-workers. Chianti-workers also showed a significantly higher frequency of very low thyroid volume (≤6.0 ml) as compared to controls. Conclusions These findings showed a mild thyroid disrupting effect due to occupational exposure to mancozeb, more pronounced in workers residing in an area characterized by a mild to moderate iodine deficiency as compared to workers residing in an area covered by a long-lasting iodine prophylaxis program. [ABSTRACT FROM AUTHOR]

Background: A recent clinical trial has shown a beneficial effect of the antioxidant agent selenium in Graves' orbitopathy (GO). In order to shed light on the cellular mechanisms on which selenium may act, this study investigated its effects in cultured orbital fibroblasts. Methods: Primary cultures of orbital fibroblasts from six GO patients and six control subjects were established. Cells were treated with H2O2 to induce oxidative stress, after pre-incubation with selenium-(methyl)selenocysteine (SeMCys). The following assays were performed: glutathione disulfide (GSSG), as a measure of oxidative stress, glutathione peroxidase (GPX) activity, cell proliferation, hyaluronic acid (HA), and pro-inflammatory cytokines. Results: H2O2 induced an increase in cell GSSG and fibroblast proliferation, which were reduced by SeMCys. Incubation of H2O2-treated cells with SeMCys was followed by an increase in glutathione peroxidase activity, one of the antioxidant enzymes into which selenium is incorporated. At the concentrations used (5 μM), H2O2 did not significantly affect HA release, but it was reduced by SeMCys. H2O2 determined an increase in endogenous cytokines involved in the response to oxidative stress and GO pathogenesis, namely tumor necrosis factor alpha, interleukin 1 beta, and interferon gamma. The increases in tumor necrosis factor alpha and interferon gamma were blocked by SeMCys. While the effects of SeMCys on oxidative stress and cytokines were similar in GO and control fibroblasts, they were exclusive to GO fibroblasts in terms of inhibiting proliferation and HA secretion. Conclusions: Selenium, in the form of SeMCys, abolishes some of the effects of oxidative stress in orbital fibroblasts, namely increased proliferation and secretion of pro-inflammatory cytokines. SeMCys reduces HA release in GO fibroblasts in a manner that seems at least in part independent from H2O2-induced oxidative stress. Some effects of SeMCys are specific for GO fibroblasts. These findings reveal some cellular mechanisms by which selenium may act in patients with GO. [ABSTRACT FROM AUTHOR]

Background: Thyroid ultrasound (US) elastography provides an estimation of tissue stiffness and is helpful to differentiate malignant from benign lesions. Tissue proprieties and molecules causing stiffness are not established. The aim of the study was to correlate US elastography findings with tissue properties in thyroid nodules. Methods: A total of 115 thyroid nodules from 112 patients who underwent surgery for the presence of Thy 3 (indeterminate) cytology (n = 67), Thy 4-5 (suspicious—indicative of carcinoma) cytology (n = 47), or large goiter in the presence of Thy 2 cytology (n = 1) and suspicious US features were examined by US elastography. Tissues obtained after surgery were characterized for cell number, microvessel density, fibrosis, and expression of galectin-3 (Gal-3) and fibronectin-1 (FN-1). Results: Low elasticity on qualitative US elastography (LoEl) was found in 66 nodules (one benign and 65 carcinomas); high elasticity (HiEl) was found in 49 nodules (46 benign and three carcinomas; p < 0.0001). Quantitative analysis, performed in 24 nodules and expressed as elastic ratio between the strain of the nodule and that of the surrounding thyroid parenchyma, showed a mean of 1.90 (interquartile range [IQR] 1.18-2.77) in 14 nodules with LoEl, and a mean of 1.01 (IQR 0.91-1.10) in 10 nodules with HiEl ( p = 0.002). Stiffness did not correlate with cell number and was inversely correlated with microvessel density. Fibrosis was higher in nodules with LoEl than in those with HiEl ( p = 0.009) and in carcinomas than in benign nodules ( p = 0.02). Fibrosis was higher in nodules with high expression of Gal-3 ( p < 0.001) and FN-1 ( p = 0.004). Fibrosis and expression of Gal-3 and FN-1 were higher in the classic compared with the follicular variant of papillary thyroid carcinoma and lower in follicular adenomas. Conclusions: Low elasticity at US elastography is highly correlated with malignancy. Nodule stiffness is correlated with fibrosis and expression of Gal-3 and FN-1. These features are more evident in the classic than in the follicular variant of papillary thyroid carcinoma. [ABSTRACT FROM AUTHOR]

Background: The management of patients with differentiated thyroid carcinoma (DTC) showing low levels of serum thyroglobulin autoantibodies (TgAb) and undetectable Tg after thyroidectomy is unsettled. This study sought to elucidate the clinical significance of low levels of TgAb and to evaluate their interference with Tg measurement in vitro. Methods: Tg and TgAb levels were correlated with the post-thyroidectomy staging of 177 consecutive DTC patients undergoing 131I ablation after total thyroidectomy (clinical study). Tg was measured by an immunometric assay (functional sensitivity: 0.1 ng/mL), and TgAb were evaluated by six assays (functional sensitivities: 1.2-96 IU/mL; positive cutoffs: 4-150 IU/mL). The changes in Tg concentration (Tg recovery) of diluted specimens from DTC patients were also measured after incubation with 67 sera from DTC patients with undetectable Tg and low levels of TgAb (in vitro study). DTC sera containing Tg were diluted serially (from 330 to 0.1 ng/mL) and incubated with TgAb samples; Tg was then measured. Results: In the clinical study: all patients had residual thyroid tissue, and 10 had metastatic disease. Depending on the TgAb assay, median Tg values were 7.0-10.9, 0.0-5.3, and 0.0-0.0 ng/mL in patients with undetectable, borderline (between functional sensitivities and positive cutoffs), and positive TgAb, respectively ( p < 0.001). An undetectable Tg value was associated with borderline levels of TgAb in five assays. Only two patients with metastatic disease had undetectable Tg; both were TgAb positive by three or more assays. Conversely, no patient with undetectable Tg and undetectable or borderline TgAb by sensitive assays had metastatic disease. In the in vitro study, TgAb interfered significantly with Tg recovery ( p < 0.001), but low levels of TgAb did not abolish Tg recovery. Conclusions: While low levels of TgAb do not preclude Tg measurement in vitro, they can be associated with an undetectable Tg in DTC patients with residual thyroid tissue after thyroidectomy. However, the finding of low levels of TgAb by sensitive assays associated with an undetectable Tg rules out metastatic disease. [ABSTRACT FROM AUTHOR]

Background: Obesity and hypothyroidism are both common disorders within the general population. Obese hypothyroid subjects require higher doses of levothyroxine (LT4) compared with normal weight individuals. Previous studies on the effects of bariatric surgery on LT4 dose requirements in hypothyroid subjects have provided conflicting results. The aim of this study was to evaluate the LT4 requirements in a group of obese subjects with acquired hypothyroidism, before and after weight loss achieved by bariatric surgery. Methods: Ninety-three obese hypothyroid subjects (mean age = 48 ± 9 years; mean body mass index = 45.9 ± 5.6 kg/m2), were evaluated before and 28 ± 8 months after bariatric surgery. Changes in the LT4 dose, anthropometric measures, and hormone values were evaluated. In 20 patients, data of body composition, assessed by dual energy X-ray absorptiometry, were also analyzed. Results: On average, after weight loss, a significant reduction of the total dose of LT4 was documented (from 130.6 ± 48.5 to 116.2 ± 38.6 μg/day; p < 0.001). The LT4 dose had to be reduced in 47 patients, was unchanged in 34, and had to be increased in 12 patients affected by autoimmune thyroiditis. Reduction of the LT4 dose was proportional to reduction of the lean body mass. Conclusions: The weight loss achieved with modern surgical bariatric procedures is associated with a reduction of LT4 requirements in most hypothyroid subjects, which appears to be related to a decrease of the lean body mass. Occasionally, a concurrent decline of residual thyroid function, as it occurs in autoimmune thyroiditis, can counteract this phenomenon and eventually produce an increase of LT4 needs. It is believed that during the weight loss phase that follows bariatric surgery, there is no need for preventive adjustments of the LT4 dose, but serum thyroid hormones and thyrotropin should be periodically monitored in order to detect possible variations of LT4 requirements and to allow proper corrections of the therapy. [ABSTRACT FROM AUTHOR]

Background: High-dose intravenous glucocorticoid (ivGC) pulse therapy, which is commonly used for Graves' orbitopathy (GO), has been associated with acute liver damage (ALD), resulting in a fatal outcome in a few cases. No certain risk factors for ALD have been established. Consequently, a large retrospective cohort study was performed. Methods: The relationship between ALD and several potential risk factors was assessed in 1076 consecutive patients with GO given ivGC. ALD was defined as an increase of alanine aminotransferase ≥300 IU/L. Results: Fourteen cases of ALD were recorded, resulting in a morbidity of 1.3%. Thirteen patients recovered and one died, resulting in a mortality of 0.09%. There was a significant, positive correlation of ALD with age and methylprednisolone acetate (MPA) cumulative dose, and ALD was more common (relative risk [RR]=2.8; p=0.05) in patients aged ≥53 years (9/420; 2.14%) than in those aged <53 years (5/656; 0.76%). In patients aged ≥53 years, there was a significant positive correlation of ALD with MPA cumulative dose, and with MPA dose per infusion. Thus, the frequency of ALD in this age group was greater (RR=3.48; p=0.04) in patients with a MPA dose per infusion ≥0.7 g (5/111, 4.5% vs. 4/308, 1.29%). Regardless of age, no cases of ALD were observed for MPA doses per infusion <0.57 g. Conclusions: Age and MPA dose are significant risk factors for ALD, with the following practical implications. First, the total MPA cumulative dose should not exceed 8.5 g (the average dose in patients without ALD). Second, in patients aged ≥53 years, selection and observation should be quite strict. However, being aged ≥53 years should not be seen as an absolute contraindication to ivGC, especially in patients with severe GO, considering that the risk of ALD, although statistically significant, was relatively low. Third, the MPA dose should not exceed 0.57 g per infusion, a measure to be applied regardless of age. [ABSTRACT FROM AUTHOR]

Objective Medullary thyroid carcinoma ( MTC) is a rare disease that can be inherited or sporadic; its pathogenesis is related to activating mutations in the RET gene. Design This study describes our 20-year experience regarding RET genetic screening in MTC. Patients and methods We performed RET genetic screening in 1556 subjects, 1007 with an apparently sporadic MTC, 95 with a familial form and 454 relatives of RET-positive patients with MTC. Results A germline RET mutation was found in 68 of 1007 (6·7%) patients with sporadic MTC, while 939 patients with MTC were negative for germline RET mutations. We then identified a total of 137 gene carriers ( GC). These subjects initiated a clinical evaluation for the diagnosis of MEN 2. A total of 139 MEN 2 families have been followed: 94 FMTC, 33 MEN 2A and 12 MEN 2B. Thirty-three different germline RET mutations were identified. Codon 804 was the most frequently altered codon particularly in FMTC (32/94, 34%), while codon 634 was the most frequently altered codon in MEN 2A (31/33, 94%); MEN 2B cases were exclusively associated with an M918T mutation at exon 16. Conclusions Our 20-year study demonstrated that RET genetic screening is highly specific and sensitive, and it allows the reclassification as hereditary of apparently sporadic cases and the identification of GC who require an adequate follow-up. We confirmed that FMTC is the most prevalent MEN 2 syndrome and that it is strongly correlated with noncysteine RET mutations. According to these findings, a new paradigm of follow-up of hereditary MTC cases might be considered in the next future. [ABSTRACT FROM AUTHOR]

Background: Clinically overt Graves' orbitopathy (GO) is associated with Graves' disease (GD) in approximately 95% of cases, whereas the remaining 5% is observed in patients with hypothyroid autoimmune thyroiditis (AT) or without overt thyroid dysfunction (euthyroid GO). However, it is not known whether there is a difference in terms of GO phenotype between patients with GD and those with hypothyroid AT or without thyroid dysfunction, and hence this is investigated here. Methods: The study design was to evaluate retrospectively all consecutive patients with a recent manifestation of GO, seen at their first visit to a tertiary referral center over a period of 10 years. In total, 358 GO patients were studied, and all of them underwent GO assessment. Results: Of the 358 patients studied, 341 had hyperthyroid GD, 10 had AT with hypothyroidism, and seven had euthyroid GO. Age, sex, and smoking habits were similar in the three groups, as was the time since GO was first noticed (GO duration). The vast majority of patients had moderate to severe, active GO, as expected in a tertiary referral center. Exophthalmometry, eyelid width, clinical activity score (CAS), diplopia, and visual acuity did not differ between patients with GD and those with AT or euthyroid GO, suggesting that the GO phenotype was similar. Accordingly, the NOSPECS score did not differ between the three groups. Conclusions: The phenotype of GO is similar regardless of the underlying thyroid disease. Because this study was performed in a tertiary referral center, this conclusion can be restricted only to patients who develop moderate to severe GO. [ABSTRACT FROM AUTHOR]

Objective: Intravenous glucocorticoid (i.v.GC) pulse therapy for Graves' ophthalmopathy (GO) can be associated with acute liver damage (ALD), which was roughly estimated to occur in w1% of patients, with an overall mortality of 0.4%. The aim of this study was to evaluate the frequency of ALD after the introduction of a series of exclusion criteria and preventive measures. Design: Retrospective evaluation of all consecutive patients candidate to i.v.GC over a period of 5 years. Methods: The study includes 376 GO patients candidate to i.v.GC. Several liver tests were performed before, during, and after i.v.GC. To prevent ALD morbidity and mortality, the following measures were applied: i) exclusion of patients with active viral hepatitis and/or severe liver steatosis; ii) reduction in the GC dose, frequency, and number of pulses; and iii) administration of oral GC after i.v.GC, and also during i.v.GC in patients positive for nonorgan-specific autoantibodies (to prevent autoimmune hepatitis due to immune rebound). ALD was defined as an increase in alanine aminotransferase R300 U/l. Results: A total of 353 patients were given i.v.GC and 23 were excluded for various conditions. ALD was detected in 4/376 patients candidate to i.v.GC, resulting in a morbidity of 1.06%. One patient recovered spontaneously and three after additional treatment with oral GC, given to re-establish immune suppression in the suspect of an autoimmune hepatitis. Conclusions: ALD related to i.v.GC is a relatively rare adverse event. Provided an accurate selection of patients and a series of preventive measures are applied, i.v.GC is a safe treatment for the liver. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effects of radioactive iodine ( RAI) treatment for differentiated thyroid cancer ( DTC) on testis function. Design A prospective longitudinal single-centre study was performed. A comprehensive andrological evaluation including hormonal assessment, semen analysis and scrotal ultrasound was undertaken in male patients undergoing RAI treatment for DTC. Methods Hormonal assessment of FSH, LH, testosterone (T), sperm concentration and motility and testis volume were determined in 20 patients in basal conditions, 6 and 12 months after RAI. Results were analysed in the whole group of patients and then separately in those who received one single ablative treatment ('Single' group, n = 10) and those who received multiple treatments ('Multiple' group, n = 10). Results In basal conditions, 3 of 20 (15%) patients had a reduced sperm count and belonged to the 'Multiple' group. After RAI, an increase of FSH (8·8 ± 1·2 UI/l vs 5·2 ± 1·2, P < 0·005) and a decrease in sperm concentration (28·8 ± 7·7 millions/ml vs 54·5 ± 7·1, P < 0·005) and testis volume (15·2 ± 3·1 vs 13·7 ± 0·8 ml, P < 0·005) occurred at 6 months in the whole group. One year after RAI, seven patients had oligozoospermia (five from the 'Multiple' group and two from the 'Single' group). Permanent impairment of one or more testis function parameters was observed in patients who underwent multiple RAI treatments: 50% for sperm count, 40% for FSH levels and testis volume and, respectively, in 20 and 10% of those who received one single RAI treatment. Conclusions The single ablative RAI treatment in cancer patients is better tolerated respect multiple RAI treatments regard testis function. Multiple treatments for recurrent or metastatic disease may cause a permanent impairment of one or more parameters related to the reproductive potential of male patients. [ABSTRACT FROM AUTHOR]

Background: Oxidative stress (OS) plays a major role on tissue function. Several catabolic or stress conditions exacerbate OS, inducing organ deterioration. Haptoglobin (Hp) is a circulating acute phase protein, produced by liver and adipose tissue, and has an important anti-oxidant function. Hp is induced in pro-oxidative conditions such as systemic inflammation or obesity. The role of systemic factors that modulate oxidative stress inside muscle cells is still poorly investigated. Results: We used Hp knockout mice (Hp-/-) to determine the role of this protein and therefore, of systemic OS in maintenance of muscle mass and function. Absence of Hp caused muscle atrophy and weakness due to activation of an atrophy program. When animals were stressed by acute exercise or by high fat diet (HFD), OS, muscle atrophy and force drop were exacerbated in Hp-/-. Depending from the stress condition, autophagy-lysosome and ubiquitin-proteasome systems were differently induced. Conclusions: Hp is required to prevent OS and the activation of pathways leading to muscle atrophy and weakness in normal condition and upon metabolic challenges. [ABSTRACT FROM AUTHOR]

Background: The forkhead transcription factor FoxP3 plays an important role in regulatory T cell (Treg) functions. Tregs are critical in maintaining immunologic tolerance. It has been shown that vaccination against FoxP3-expressing cells is associated with enhancement of tumor immunity. Tregs appear to be increased in blood and in the tumor microenvironment of patients with different cancer types. Tumor cells themselves can express FoxP3. The present study investigates the possible role of FoxP3 expression in a series of human papillary thyroid cancers with a mean follow-up time of 15 years. Methods: One hundred five cases of papillary thyroid carcinoma (PTC) were investigated, and FoxP3 expression was evaluated in both tumor cells and tumor-associated infiltrates. For all patients, clinical/pathologic features were considered and the results analyzed by statistical tests. Results: Of the 105 PTC cases, 45 (43%) scored FoxP3-positive and 60 (57%) were negative. FoxP3 staining was localized predominantly in the cytoplasm of tumor cells. In some cases, both nuclear and cytoplasmic staining was seen in infiltrating cells. FoxP3 expression in tumor cells was correlated with the presence of extrathyroid invasion ( p=0.04) and distant metastasis ( p=0.04), but not with overall survival. Interestingly, FoxP3 expression in neoplastic cells was significantly associated with a resistance phenotype to radioiodine treatment ( p=0.041). Conclusions: The data show an association of FoxP3 expression with features of PTC that seem to have a specific impact on radioiodine sensitivity. [ABSTRACT FROM AUTHOR]

Background: According to Rundle's curve, Graves' ophthalmopathy (GO) worsens during an initial phase up to a peak of maximum severity, then improves and reaches a static plateau, with the activity curve preceding the severity curve by a few months. To our knowledge, no studies have tried to replicate Rundle's curve, and very few have investigated the natural history of GO. Here, we studied GO natural history retrospectively and tried to identify factors that may affect it. Methods: A total of 65 patients with untreated GO underwent an eye assessment after a median of seven months after the appearance of GO and then after a median of 40 months. The primary endpoints were the variation of the single GO features and of the NOSPECS score, as well as the overall outcome of GO. The secondary endpoint was the influence of several variables (age, sex, smoking, GO and thyroid disease duration, thyroid treatment, thyroid status, thyroid volume, anti-TSH receptor autoantibodies) on the outcome of GO. Results: The majority of patients had mild, minimally active GO, and only five had a Clinical Activity Score (CAS) >3. There was a significant reduction of CAS ( p<0.0001) and NOSPECS ( p=0.01) between the first and last observation, with a timing pattern resembling Rundle's curve. This difference was confirmed even when patients with a CAS >3 at first observation were excluded. At the last observation, 50.8% of patients had improved, 33.8% had remained stable, and 15.4% had worsened moderately or substantially. The overall outcome of GO was not affected by any of the variables under examination. Conclusions: In confirmation of Rundle's observations, untreated GO improves spontaneously with time in the majority of patients, with an activity peak between 13 and 24 months, which may have implications in determining the proper timing of GO treatments. [ABSTRACT FROM AUTHOR]

Background Serotonin (5-HT) is a well-known modulator of eating behavior. However, the molecular mechanisms linking its action to body weight balance have been only partially elucidated. Since platelets are a suitable peripheral model to study 5-HT transport, metabolism and release, we herein evaluated the expression of the platelet 5-HT re-uptake system (SERT) by [3H]-paroxetine binding assay. A cohort of 114 unrelated individuals (34 males, 80 females; age, mean ± SD: 38.57 ± 12.47 years) without major psychiatric disorders, was recruited following a naturalistic design regarding age or gender and classified accordingly to their body mass index (BMI). Subjects were divided into 5 groups: normal-weight (NW), overweight (OW) and grade I-III obese (OB) individuals. For gender analyses, data were transformed into [3H]-paroxetine density (Bmax)/BMI ratios to overcome both the disparity of women vs. men number and anthropometric differences between sexes. Results [3H]-paroxetine Bmax (SERT density, fmol/mg proteins) was reduced in platelet membranes of grade II (p < 0.01) and III (p < 0.001) obese subjects vs. controls and in overweight subjects (p < 0.05) vs. grade III obese individuals. Considering all patients together, a strong negative correlation between Bmax and BMI (r = -0.449; P < 0.0001) was demonstrated. Conversely, [3H]-paroxetine KD (dissociation constant, nM) did not differ among groups. No gender-related variation concerning Bmax/BMI ratios was observed in this cohort of subjects. Conclusions The down-regulation of SERT in platelet membranes of severe human obesity (BMI > 35 Kg/m2) confirms the involvement of 5-HT system in body weight gain. Moreover, this findings may help to elucidate those monoamine-endocrine networks acting on fat storage, adipocyte signaling and energy balance. Targeting 5-HT/5-HT-related markers will possibly uncover the existence of human obesity subtypes. [ABSTRACT FROM AUTHOR]

Fine-needle aspiration biopsy (FNA) is usually applied to distinguish benign from malignant thyroid nodules. However, cytological analysis cannot always allow a proper diagnosis. We believe that the improvement of the diagnostic capability of pre-surgical FNA could avoid unnecessary thyroidectomy. In a previous study, we performed a proteome analysis to examine FNA collected after thyroidectomy. With the present study, we examined the applicability of these results on pre-surgical FNA. We collected pre-surgical FNA from 411 consecutive patients, and to obtain a correct comparison with our previous results, we processed only benign (n = 114), papillary classical variant (cPTC) (n = 34) and papillary tall cell variant (TcPTC) (n = 14) FNA. We evaluated levels of five proteins previously found up-regulated in thyroid cancer with respect to benign nodules. ELISA and western blot (WB) analysis were used to assay levels of L-lactate dehydrogenase B chain (LDHB), Ferritin heavy chain, Ferritin light chain, Annexin A1 (ANXA1), and Moesin in FNA. ELISA assays and WB analysis confirmed the increase of LDHB, Moesin, and ANXA1 in pre-surgical FNA of thyroid papillary cancer. Sensitivity and specificity of ANXA1 were respectively 87 and 94% for cPTC, 85 and 100% for TcPTC. In conclusion, a proteomic analysis of FNA from patients with thyroid nodules may help to distinguish benign versus malignant thyroid nodules. Moreover, ANXA1 appears to be an ideal candidate given the high sensitivity and specificity obtained from ROC curve analysis. [ABSTRACT FROM AUTHOR]

Congenital hypothyroidism (CH) due to thyroglobulin (TG) deficit is an autosomal recessive disease (OMIM #274700) characterized by hypothyroidism, goiter, low serum TG, and a negative perchlorate discharge test. The aim of this study was to perform the genetic analysis of the TG gene in two sisters born from consanguineus parents and affected by CH and low serum TG levels. The index patient and her sister were identified at neonatal screening for CH and treated with L-thyroxine (L-T4). After discontinuation of L-T4 therapy, hypothyroidism was confirmed, serum TG was undetectable, and no organification defect after I scintigraphy and perchlorate test was shown; thyroid ultrasound showed a eutopic gland of normal size. DNA was extracted from peripheral white blood cells of the two sisters and the father. All 48 exons of TG gene were amplified by polymerase chain reaction and subjected to direct sequencing. A novel homozygous point mutation in exon 10 of TG gene was identified in the patient and her sister. The mutation determined a stop codon at position 768 (R768X) resulting in an early truncated protein or in the complete absence of the protein. The father (euthyroid) was heterozygous carrier of the mutation. Conclusion: Genetic analysis of TG gene was performed in two sisters affected by CH. A novel point mutation of the TG gene determining a stop codon at position 768 of the protein was identified. The early truncated nonfunctioning protein or the absence of the protein due to the premature degradation of abnormal mRNA may be responsible of the observed phenotype. [ABSTRACT FROM AUTHOR]

Background: Graves' orbitopathy (GO) is thought to be related to one or more autoantigens present in the thyroid and in orbital tissues. Although this may not imply a quantitative relation between thyroid antigens and degree of GO, which in turn is a risk factor for a more pronounced GO, we postulated that the severity of GO may parallel the amount of thyroid tissue, namely, the size of the thyroid gland. This hypothesis is also based on the observation that patients with Graves' disease presenting with large goiters tend to have more severe hyperthyroidism. Thus, we evaluated retrospectively whether there is a correlation between the degree of GO at its first observation and, among other parameters, the thyroid volume. Methods: Eighty-six consecutive patients with untreated GO lasting for no longer than 24 months underwent an endocrinological and an ophthalmological evaluation, the latter including: exophthalmometry, eyelid width, clinical activity score (CAS), diplopia, and visual acuity. The overall degree of GO was ranked using the NOSPECS score as well as a modification of the NOSPECS score. The following parameters were considered for correlations: time since GO appearance, time since detection of hyperthyroidism, FT3, anti-thyrotropin receptor antibodies, thyroid volume, and cigarette-years. Results: Thyroid volume, but not the other parameters, correlated significantly by simple regression with exophthalmometry ( p=0.02) and CAS ( p=0.02). The standard NOSPECS score correlated with FT3 ( p=0.05), thyroid volume ( p=0.02), and cigarette-years ( p=0.03), by simple, but not by multiple regression analysis. The modified NOSPECS score correlated with thyroid volume ( p=0.007) and cigarette-years ( p=0.04) by simple regression, and with thyroid volume also by multiple regression analysis ( p=0.05). Conclusions: Thyroid volume correlates with the severity of GO at its first observation, especially with exophthalmometry and CAS. The finding is in line with a possible pathogenetic role of antigens shared by the thyroid and orbital tissues. Nevertheless, other mechanisms may explain this observation, including an overall more reactive immune system in patients with a large goiter, resulting in more severe thyroid and eye disease, regardless of the nature of the autoantigen, or whether it is shared by the thyroid and the orbit. [ABSTRACT FROM AUTHOR]

Background: Orbital fibroblast proliferation and hyaluronic acid (HA) release are responsible for some of the clinical features of Graves' ophthalmopathy (GO). Thus, inhibition of these processes may be a possible therapeutic approach to this syndrome. Enalapril, a widely used antihypertensive drug, was found to have some inhibitory actions on fibroblast proliferation in cheloid scars in vivo, based on which we investigated its effects in primary cultures of orbital fibroblasts from GO patients and control subjects. Methods: Primary cultures of GO and control fibroblasts were treated with enalapril or with a control compound (lisinopril). Cell proliferation assays, lactate dehydrogenase release assays (as a measure of cell necrosis), apoptosis assays, and measurement of HA in the cell media were performed. Results: Enalapril significantly reduced cell proliferation in both GO and control fibroblasts. Because enalapril did not affect cell necrosis and apoptosis, we concluded that its effects on proliferation reflected an inhibition of cell growth and/or a delay in cell cycle. Enalapril significantly reduced HA concentrations in the media from both GO and control fibroblasts. Conclusions: Enalapril has antiproliferative and HA suppressing actions in both GO and control fibroblasts. Clinical studies are needed to investigate whether enalapril has any effects in vivo in patients with GO. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Premature ovarian insufficiency (POI) is defined as a primary ovarian defect characterized by absent menarche (primary amenorrhea) or premature depletion of ovarian follicles before the age of 40 (secondary amenorrhea) with hypergonadotropism and hypoestrogenism. Methods: We studied the clinical, biological, and genetic data related to 50 POI patients with a mean age of menopause of 29years (94% with secondary amenorrhea, 6% with primary amenorrhea and 15% with a family history of POI). Seventeen patients were affected by endocrine autoimmune diseases, antral follicles were observed in 31 patients by ultrasonography. Results: Karyotype analysis did not show any abnormality of the X chromosome. No mutation in FSH receptor and GDF-9 genes was reported, while in one patient a variant of BMP-15 gene (A180T) was found. Four patients had fragile X mental retardation 1 gene (FMR1) premutation and one an intermediate sized CGG repeats of the same gene. Two patients with FMR1 premutation were sister and developed secondary amenorrhea at the age of 34 and 37years. The other two patients presented with oligoamenorrhea at the age of 39 and 34years. The patient harboured the intermediate sized CGG repeats developed secondary amenorrhea at the age of 33years. Conclusions: The genetic analysis performed on a cohort of patients with POI revealed that 8% had FMR1 premutation and only one patient a previously known variant of BMP-15 gene. No alteration of the karyotype and FSH receptor and GDF-9 genes was evidenced. [Copyright &y& Elsevier]

Background: Patients with moderate to severe Graves' orbitopathy (GO) rather frequently require rehabilitative surgery after medical therapy. Diplopia is the most common side effect of orbital decompression (OD). The aim of this study was to evaluate the occurrence of postoperative diplopia in primary gaze after OD, and the influence of the surgical approach on this outcome. Moreover, we investigated the results in terms of proptosis reduction, and the long-term subjective satisfaction of patients treated with OD with regard to their appearance and ocular function. Methods: A retrospective evaluation of 247 patients with GO treated with medial and lateral decompression (MLD) or lateral decompression (LD) OD between January 2002 and December 2009 was performed. Results: The overall prevalence of postoperative diplopia in primary gaze was 55/247 (22.3%), with a statistically significant difference ( p<0.001) between patients with (36/113, 31.2%) and those without (19/134, 14.2%) preoperative diplopia in secondary gaze. The surgical procedure influenced the outcome in patients without preoperative diplopia (17.8% after MLD and 0% after LD, p=0.02), but not in patients with preoperative diplopia in secondary gaze (33.3% after MLD and 26.1% after LD, p=0.5). Overall, proptosis reduction was 5.7±2.2 mm (1-11 mm), after MLD and 4.0±1.6 mm (1-8 mm) after LD ( p<0.001). Fifty-one out of 55 patients with constant, postoperative diplopia in primary gaze after OD underwent squint surgery, which was successful in all but two. Four patients refused squint surgery. Patients were also interviewed for satisfaction in terms of recovery of their appearance and ocular function after a mean of 6 years from surgery (range 2-9 years): more than 85% of patients reported a good to excellent postoperative satisfaction for both items. Conclusions: Preoperative diplopia in secondary gaze is a risk factor for the development of diplopia in primary gaze after OD, independently of the surgical approach (MLD vs. LD). In absence of diplopia, MLD, but not LD, seems to be associated with its development in primary gaze. The reduction in proptosis after MLD is greater than that after LD. Most patients were satisfied with the results of both appearance and ocular function after OD. [ABSTRACT FROM AUTHOR]

Objective: MicroRNAs (miRNAs) are small endogenous noncoding RNAs that pair with target messengers regulating gene expression. Changes in miRNA levels occur in thyroid cancer. Fine-needle aspiration (FNA) with cytological evaluation is the most reliable tool for malignancy prediction in thyroid nodules, but cytological diagnosis remains undetermined for 20% of nodules. Design: In this study, we evaluated the expression of seven miRNAs in benign nodules, papillary thyroid carcinomas (PTCs), and undetermined nodules at FNA. Methods: The prospective study included 141 samples obtained by FNA of thyroid nodules from 138 patients. miRNA expression was evaluated by quantitative RT-PCR and statistical analysis of data was performed. Genetic analysis of codon 600 of BRAF gene was also performed. Results: Using data mining techniques, we obtained a criterion to classify a nodule as benign or malignant on the basis of miRNA expression. The decision model based on the expression of miR-146b, miR-155, and miR-221 was valid for 86/88 nodules with determined cytology (97.73%), and adopting cross-validation techniques we obtained a reliability of 78.41%. The prediction was valid for 31/53 undetermined nodules with 16 false-positive and six false-negative predictions. The mutated form V600E of BRAF gene was demonstrated in 19/43 PTCs and in 1/53 undetermined nodules. Conclusions: The expression profiles of three miRNAs allowed us to distinguish benign from PTC starting from FNA. When the assay was applied to discriminate thyroid nodules with undetermined cytology, a low sensitivity and specificity despite the low number of false-negative predictions was obtained, limiting the practical interest of the method. [ABSTRACT FROM AUTHOR]

Germline mutations of thyrotropin receptor ( TSHR) gene determining a constitutive activation of the receptor were identified as a molecular cause of familial or sporadic congenital nonautoimmune hyperthyroidism (OMIM: 609152) (Nat Genet 7:396-401, ; N Engl J Med 332:150-154, ; Acta Endocrinol (Copenh) 100:512-518, ). We report the case of an Italian child subjected to the first clinical investigation at 24 months for an increased growth velocity; biochemical investigation showed high FT4 and FT3 serum values and undetectable thyrotropin in the absence of anti-thyroid antibodies; the thyroid gland was normal at ultrasound examination. Treatment with methimazole was started at the age of 30 months when her growth velocity was high and the bone age was advanced. DNA was extracted from her parents', brother's, and the patient's blood. Exons 9 and 10 of the TSHR gene were amplified by polymerase chain reaction and subjected to direct sequencing. In proband, a heterozygous substitution of cytosine to thymine determining a proline to serine change at position 639 (P639S) of the TSHR was detected while the parents and brothers of the propositus, all euthyroid, showed only the wild-type sequence of the TSHR gene. This mutation was previously described as somatic in patients affected by hyperfunctioning thyroid nodules and as germline in a single Chinese family affected by thyrotoxicosis and mitral valve prolapse. This constitutively activating mutation is able to activate both the cyclic AMP and the inositol phosphate metabolic pathways when expressed in a heterologous system. In conclusion, we describe the first case of sporadic congenital nonautoimmune hyperthyroidism caused by de novo germinal P639S mutation of TSHR. [ABSTRACT FROM AUTHOR]

Background: The prevalence of RET somatic mutations in sporadic medullary thyroid cancer (MTCs) is ∼40%-50%, and the most frequent somatic mutation is M918T. RET-positive MTCs have been demonstrated to have a more advanced stage at diagnosis and a worse outcome. Aims: The aim of the present work was to compare the prevalence of RET somatic mutations in sporadic microMTCs (<1 cm) and in larger MTCs. Patients: We analyzed the M918T RET point mutation in 160 sporadic MTC cases. Tumors were classified according to their size: group A, <1 cm; group B, >1 and <2 cm; group C, >2 and <3 cm; and group D, >3 cm. Results: The overall prevalence of the somatic M918T RET mutation was 19.4% (31/160). RET mutations were distributed differently among the four groups. The prevalence was 11.3% (6/53) in group A, 11.8% (8/68) in group B, 31.8% (7/22) in group C, and 58.8% (10/17) in group D, exhibiting an increase with increasing size of the tumor. When comparing the prevalence of mutations in the four groups, we found a lower prevalence in microMTCs ( p<0.0001). Conclusions: The overall prevalence of RET somatic mutations was lower than expected, and the prevalence of the somatic M918T RET mutation was significantly lower in microMTCs than in larger tumors. To explain this finding, we can hypothesize either that other oncogene(s) might be responsible for the majority of microMTC, thus identifying a tumor subset, or that the RET mutation might, or might not, occur later during tumor progression. [ABSTRACT FROM AUTHOR]