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Anaplastic thyroid carcinomas (ATCs) are rare cancers with a globally very poor prognosis, because of their immensely aggressive behaviour, resulting in predominantly advanced stage of disease at diagnosis. Response to available therapies is still disappointing. Aim of the present review is to illustrate the diverse new strategies under investigation, to improve the poor outcome of these patients.Applying molecular analysis in ATC is unravelling potentially actionable targets of therapy. If a mutation of BRAF V600E is found, a combination of Dabrafenib and Trametinib is the recommended treatment. In the presence of another druggable mutation, a specific targeted therapy may be proposed. In the absence of druggable mutations, immunotherapy is an alternative approach, especially in case of significant PD-L1 expression.The molecular profiling of tumour samples is elucidating the genetic alterations involved in ATC development, and new preclinical models are under study to define innovative approaches for individualized treatment of such patients. Hopefully this approach could improve ATC prognosis.

The neoplastic proliferation of parafollicular thyroid cells (C cells) may occur as either medullary thyroid carcinoma (MTC) or C cell hyperplasia (CCH) and is generically defined C cell disease. Since Calcitonin (CT) expression is fully maintained in neoplastic C cells, this hormone represents a sensitive marker for neoplasia of C cell derivation such as CCH and MTC. Serum CT levels display a high prognostic value and accurate estimation of tumor burden, allowing early detection of persistence/relapse and representing a reliable marker of response to treatment. Indeed, elevated CT levels can occur in other non-C cell-related conditions (i.e., other malignancies, systemic diseases, and pharmacological treatments). Moreover, some de-differentiated, more aggressive MTCs may present disproportionately low-circulating CT levels, as compared with tumor burden. During the postsurgical follow-up of MTC patients, CT levels usually parallel tumor progression and their increase unambiguously announces persistence/relapse. In this respect, CT Doubling Time (DT) has been proposed as prognostic factor of potential use for the identification of more aggressive MTCs. The present review will summarize the novel achievements on the clinical suitability of CT as a biomarker in clinical oncology and will point the attention to the most recent results concerning the usefulness and the possible drawbacks of circulating CT as a surrogate marker for the identification of rapidly progressing MTC patients, such as those candidate to targeted therapies. The emerging role of circulating CT as a parameter of response to local and systemic therapies will also be illustrated.

Radioiodine-refractory thyroid cancers represent the main cause of thyroid cancer-related death. At present, targeted therapies with multikinase inhibitors represent a unique therapeutic tool, though they have limited benefit on patient survival and severe drug-associated adverse events. This review summarizes current treatment strategies for radioiodine-refractory thyroid cancer and focuses on novel approaches to redifferentiate thyroid cancer cells to restore responsiveness to radioiodine administration.We summarize and discuss recent clinical trial findings and early data from real-life experiences with multikinase-inhibiting drugs. Possible alternative strategies to traditional redifferentiation are also discussed.The current review focuses primarily on the major advancements in the knowledge of the pathophysiology of iodine transport and metabolism and the genetic and epigenetic alterations occurring in thyroid neoplasia as described using preclinical models. Results of clinical studies employing new compounds to induce thyroid cancer cell redifferentiation by acting against specific molecular targets are also discussed. Finally, we describe the current scenario emerging from such findings as well as future perspectives.

Purpose of review Several molecularly targeted drugs for treating radioiodine resistant differentiated thyroid carcinomas (RAIR-DTC) have been identified. Among these, sorafenib and lenvatinib have been approved for clinical use in many countries. The present review will analyze efficacy and safety 'real-world' data (RWD) emerging after their commercialization. Recent findings RWDs confirmed sorafenib and lenvatinib efficacy in terms of progression-free survival and, perhaps, overall survival improvement in patients with RAIR-DTC. Lenvatinib performance in RWDs appeared somehow lower than in randomized clinical trials (RCT), probably because the decision to start treatment in 'real life' was made when patients were in worse clinical conditions than in RCTs. Concerning safety, RWD studies corroborated RCT evidence of elevated overall and serious adverse event incidence. Notably, adverse events were manageable in most cases with appropriate treatment or dose reduction/interruption, so that the need for definitive withdrawal was limited. The suitability of multikinase inhibitors (MKI) as salvage therapy in RAIR-DTCs was also confirmed by RWD experience, at least for lenvatinib in the second-line setting. Summary RWD analysis has corroborated RCT results in terms of MKI efficacy for both first-line and salvage treatment in patients with RAIR-DTC. The safety profiles emerging from RWDs seem to justify the caution recommended by most scientific guidelines.

Context:The European Thyroid Association (ETA) has classified posttreatment cervical ultrasound findings in thyroid cancer patients based on their association with disease persistence/recurrence.Objective:The objective of the study was to assess this classification's ability to predict the growth and persistence of such lesions during active posttreatment surveillance of patients with differentiated thyroid cancer (DTC).Design:This was a retrospective, observational study.Setting:The study was conducted at a thyroid cancer center in a large Italian teaching hospital.Patients:Center referrals (2005–2014) were reviewed and patients selected with pathologically-confirmed DTC; total thyroidectomy, with or without neck dissection and/or radioiodine remnant ablation; abnormal findings on two or more consecutive posttreatment neck sonograms; and subsequent follow-up consisting of active surveillance. Baseline ultrasound abnormalities (thyroid bed masses, lymph nodes) were classified according to the ETA system. Patients were divided into group S (those with one or more lesions classified as suspicious) and group I (indeterminate lesions only). We recorded baseline and follow-up clinical data through June 30, 2015.Main Outcomes:The main outcomes were patients with growth (>3 mm, largest diameter) of one or more lesions during follow-up and patients with one or more persistent lesions at the final visit.Results:The cohort included 58 of the 637 DTC cases screened (9%). A total of 113 lesions were followed up (18 thyroid bed masses, 95 lymph nodes). During surveillance (median 3.7 y), group I had significantly lower rates than group S of lesion growth (8% vs 36%, P = .01) and persistence (64% vs 97%, P = .014). The median time to scan normalization was 2.9 years.Conclusions:The ETA's evidence-based classification of sonographically detected neck abnormalities can help identify papillary thyroid cancer patients eligible for more relaxed follow-up.

Corticosteroid agents (CA) are widely used in the treatment of metastatic castration-resistant prostate cancer (mCRPC) either as concomitant treatment with active agents such as docetaxel, cabazitaxel and abiraterone or in a palliative setting, predominantly due to their anti-inflammatory activity. However, the chronic use of CA has numerous side effects, especially in case of steroid-induced adrenal insufficiency. Furthermore, the latest clinical and preclinical data demonstrate that CA themselves are likely to promote tumour progression in certain populations of patients with mCRPC. Therefore, the role of CA in advanced disease should be carefully weighed for each patient and their withdrawal should be considered in some patients. This is necessary, especially in clinical trials that need good performance status patients to evaluate the activity and the safety of emerging drugs in mCRPC that do not require the concurrent use of CA. In oncology, there is no consensus on an algorithm of gradual steroid tapering and frequently the approach to this procedure is empirical. An algorithm is presented in this article based on clinical observations. Prospective studies are necessary to evaluate the efficacy and safety of the above-proposed algorithm in metastatic castration-resistant prostate cancer.

The neoplastic proliferation of parafollicular thyroid cells (C cells), generically defined as C cell disease, may occur as either medullary thyroid carcinoma (MTC) or C cell hyperplasia (CCH).

SummaryIntroduction A relationship between vestibular disorders and thyroid autoimmunity independently from thyroid function has been postulated. Aim To shed more light on the actual relationship between vestibular lesions and Hashimoto's thyroiditis (HT) regardless of thyroid function. Methods Forty-seven patients with HT (89·4% F; aged 48·3 ± 12·7 years), 21 with multinodular goitre (MNG; 57·1% F; 54·1 ± 9·8 years) and 30 healthy volunteers (56·7% F; 50·7 ± 13·9 years) were enrolled. Inclusion criteria were the presence of normal thyroid function tests and no clinical history of vestibular dysfunction. Each subject was submitted to complete vestibular evaluation [Caloric Test, Vestibular evoked myogenic potentials (VEMPs), Head Shaking Test (HST)]. Results 52·2% of HT patients showed an alteration of VEMPs and 44·7% of caloric test (P

The demography of differentiated thyroid cancers (DTCs) has changed considerably since the 1990s, when the vast majority of these tumors were clinically evident at the time of diagnosis, and many were associated with regional lymph node involvement. Today's DTCs are more likely to be small, localized, asymptomatic papillary forms that are discovered incidentally, during neck imaging procedure performed for other reasons or during postoperative assessment of a gland removed for benign nodular goiter. The tools available for diagnosing, treating, and monitoring DTCs have also changed and their diagnostic capacities have increased. For these reasons, DTC treatment and follow-up paradigms are being revised to ensure more appropriate, cost-effective management of the current generation of DTCs. This review examines some of the key issues in this area, including the assessment of risks for disease recurrence and thyroid cancer-related death, the indications for postoperative ablation of the thyroid remnant with radioactive iodine and TSH-suppressive doses of levothyroxine, the pros, cons, and rationales for the use of various follow-up tools (serum thyroglobulin assays, neck ultrasound, 2-[18F]fluoro-2-deoxyglucose–positron emission tomography, and whole-body131I scintigraphy), and temporal strategies for maximizing their efficacy. An algorithm is presented for individualized, risk-tailored management of DTC patients.

The term "nodular goiter" has long been used to refer to a nodular thyroid gland, based on the assumption that nodule growth may be associated with hyperplasia of the surrounding non-nodular tissue. The aim of this prospective, multicenter, observational study was to determine whether nodule growth is accompanied by growth in the non-nodular tissue.Eight Italian thyroid-disease referral centers enrolled 992 consecutive patients with one to four benign nodules. Nodular and non-nodular thyroid tissue volumes were assessed for five years with annual ultrasound examinations.In participants whose nodules remained stable (n = 839), thyroid volumes did not change (baseline 15.0 mL [confidence interval (CI) 14.5-15.6]; five-year evaluation 15.1 mL [CI 14.5-15.7]). In participants with significant growth of one or more nodule (n = 153), thyroid volumes increased and by year 5 were significantly greater than those of the former group (17.4 mL [CI 16-18.7]). In 76 individuals with unilateral nodules that grew, the mean nodular lobe volume significantly exceeded that of the contralateral lobe (8.6 mL [CI 7.4-9.8] vs. 6.7 mL [CI 6-7.4]). The unaffected lobe volumes remained stable over time, while nodular lobes grew steadily and were significantly greater at the end of follow-up (10.1 mL [CI 8.9-11.3]). Excluding the volume of the largest growing nodule in these cases, the remaining volume of the affected lobe remained virtually unchanged with respect to its baseline value. Furthermore, there was no significant difference in the non-nodular tissue volume between the unaffected lobe and the affected lobe (with the largest growing nodule volume subtracted), both at baseline and at the end of follow-up.The growth of thyroid nodules is a local process, not associated with growth of the surrounding non-nodular tissue. Therefore, a normal-sized thyroid containing nodules should be referred to as a "uni- or multinodular thyroid gland" and considered a distinct entity from "uni- or multinodular goiter."

Objective: The aim of this review was to analyze the existing literature concerning the relationship between Hashimoto thyroiditis (HT) and vestibular dysfunction. Methods: We used electronic databases (PubMed, EMBASE, Cochrane Library) to search and collect all published articles about the association between HT and vestibular disorders. Results: Several observational and retrospective studies have postulated a relationship between thyroid autoimmunity and vestibular disorders. In most cases, an appropriate control group was lacking, and the impact of thyroid functional status could not precisely be established. In recent years, two well-designed prospective studies have provided convincing evidence that the association is not random. One article reported that patients with Meniere disease (MD) had a significantly higher prevalence of positive anti-thyroid autoantibody as compared to healthy controls. Moreover, more than half of MD patients had either positive anti-thyroid or non–organ-specific autoantibody titers, compared to less than 30% of both patients with unilateral vestibular paresis without cochlear involvement and healthy controls. Another study found that patients with benign paroxysmal positional vertigo (BPPV) had significantly higher serum thyroid-stimulating hormone and antithyroid autoantibody levels than healthy controls. Additionally, almost one-fifth of euthyroid patients with HT had signs of BPPV. Conclusion: The published results indicate that patients with MD or BPPV are potential candidates to also develop HT. Thus, in HT patients, the presence of even slight symptoms or signs potentially related to vestibular lesions should be carefully investigated. Abbreviations: AITD = autoimmune thyroid disease; BPPV = benign paroxysmal positional vertigo; EH = endolymphatic hydrops; HT = Hashimoto thyroiditis; L-T4 = L-thyroxine; MD = Meniere disease; PS = Pendred syndrome; Tg = thyroglobulin; TPO = thyroid peroxidase; TSH = thyroid-stimulating hormone

The systemic efficacy of the chemotherapeutic agents presently used to treat solid tumors is limited by their low therapeutic index. Previously, our research group improved the in vitro antitumoral activity of gemcitabine, an anticancer agent rapidly deaminated to the inactive metabolite 2',2'-difluorodeoxyuridine, entrapping it into unilamellar pegylated liposomes made up of 1,2-dipalmitoyl-snglycero-3-phosphocholine monohydrate/cholesterol/N-(carbonyl-methoxypolyethylene glycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (6:3:1 molar ratio). In this work, we investigated the in vivo efficiency of the gemcitabine liposomal formulation (5mg/kg) with respect to the antitumoral commercial product GEMZAR (50mg/kg) on an anaplastic thyroid carcinoma xenograft model obtaining similar effects in terms of inhibition of tumor mass proliferation after 4weeks of treatment. The investigation of the carrier biodistribution and the drug pharmacokinetic profile furnished the rationalization of the efficacy of the vesicular system containing the active compound 10-fold less concentrated; in fact, liposomes promoted the concentration of the drug inside the tumor and they increased its plasmatic half-life. In addition, no signs of blood toxicity were observed when vesicular devices of effective doses of the drug were used.

Because virtually all medullary thyroid cancers (MTCs) are associated with elevated circulating levels of serum calcitonin (CT), routine CT measurement has been proposed as a tool for early MTC diagnosis. The usefulness of universal screening with CT in thyroid nodular disease patients is, however, controversial. Basal CT determination, in fact, displays a high false-positive rate, resulting in low positive predictive value (PPV). Provocative tests (i.e., pentagastrin or calcium gluconate administration) are often necessary to improve the specificity of the screening procedure. Nonetheless, surgical pathology indicates C-cell hyperplasia (CCH) in a substantial proportion of thyroid nodular disease patients who display positive results at CT testing (basal and/or stimulated). A basal CT >100 pg/ml is the most reliable cutoff for MTC. Below this cutoff, the threshold for discriminating CCH from MTC is not well defined.

Item does not contain fulltext BACKGROUND: Current surgical standard of care in sporadic medullary thyroid carcinoma (sMTC) consists of a minimum of total thyroidectomy with central neck dissection. Some have suggested thyroid lobectomy with isthmusectomy and central neck dissection for patients with sMTC, given their lower frequency of bilateral disease, although this topic has not been thoroughly studied. This study assessed the prevalence of multifocality in sMTC via a large international multi-institutional retrospective review to quantify this prevalence, including the impact of geography, to assess more accurately the risks associated with alternative surgical approaches. METHODS: A retrospective chart review of sMTC patients from 11 institutions over 29 years (1983-2011) was undertaken. Data regarding focality, extent of disease, RET germline analysis plus family and clinical history for multiple endocrine neoplasia type 2 (MEN2), and demographic data were collected and analyzed. RESULTS: Patients from four continents and seven countries were included in the sample. Data for 313 patients with documented sMTC were collected. Of these, 81.2% were confirmed with negative RET germline testing, while the remaining 18.8% demonstrated a negative family history and no manifestations of MEN2 syndromes other than MTC. Bilateral disease was identified in 17/306 (5.6%) patients, while multifocal disease was noted in 50/312 (16.0%) sMTC patients. When only accounting for germline negative patients, these rates were not significantly different (5.6% and 17%, respectively). Among them, when disease was unifocal in the ipsilateral lobe and isthmus, bilateral disease was present in 6/212 (2.8%) cases. When disease was multifocal in the ipsilateral lobe or isthmus, then bilateral disease was present in 8/37 (21.6%) cases (p < 0.001). No geographic differences in focality were identified. CONCLUSIONS: The 5.6% prevalence of bilateral foci in sMTC suggests that total thyroidectomy should remain the standard of care for initial surgery, as less complete thyroid surgery may fail to address fully the primary site of disease. Whether ipsilateral tumor focality should be an independent factor determining the need for completion thyroidectomy when sMTC is diagnosed after hemithyroidectomy remains to be determined.

Efficient treatment of radio refractory thyroid cancer is still a major challenge. The recent identification of genetic and epigenetic alterations present in almost all differentiated tumors has revealed novel molecular targets, which can hopefully be exploited to create new treatments for these tumors. This review looks briefly at some of the innovative strategies currently being investigated for the treatment the radioiodine-resistant thyroid cancers.

Objective: We report the case of a female patient with multiple endocrine neoplasia type 2A (MEN2A) who was found to have a double mutation in the RET (rearranged during transfection) proto-oncogene. Methods:RET mutational analysis was performed by Sanger DNA sequencing. Results: The proband was a compound heterozygote for the RET germline mutations Val648Ile and Val804Leu on exons 11 and 14, respectively. Genetic analysis of family members showed the presence of the Val648Ile mutation in all except 1 daughter who carried the Val804Leu mutation. However, none of them showed any clinical, biochemical, or histologic signs of neoplastic disease either in the thyroid or adrenal gland. Furthermore, a daughter and the proband's sister who underwent a prophylactic thyroidectomy did not show pathologic evidence of C-cell disease. Conclusions: We hypothesize that the combined effect of the 2 mutations may have induced the development of pheochromocytoma (PHEO) in our patient. Thus, in the presence of single RET-induced mild medullary thyroid cancer (MTC) phenotype, the search for additional genetic anomalies may lead to the discovery of rare but potentially more aggressive double mutation genotypes. Abbreviations: ACTH = adrenocorticotropic hormone ATA = American Thyroid Association CT = calcitonin FMTC = familial medullary thyroid cancer HSCR = Hirschsprung disease MEN2A/B = multiple endocrine neoplasia type 2A/2B MTC = medullary thyroid cancer PHEO = pheochromocytoma RET = rearranged during transfection SDHB/D = succinate dehydrogenase subunits B/D VHL = Von Hippel-Lindau

BACKGROUND: Small papillary thyroid carcinomas have contributed to the worldwide increased incidence of differentiated thyroid cancer observed over the past decades. However, the mortality rate has not changed over the same period of time, raising questions about the possibility that thyroid cancer patients, especially those with small tumors, are overdiagnosed and overtreated. Molecular prognostic marker able to discriminate aggressive thyroid cancers from those with an indolent course would be of great relevance to tailor the therapeutic approach and reduce overtreatment. Mutations in the TERT promoter were recently reported to correlate strongly with aggressiveness in advanced forms of thyroid cancer, holding promise for a possible clinical application. The occurrence and potential clinical relevance of TERT mutations in papillary thyroid microcarcinomas (mPTCs) is currently unknown. This study aimed to analyze the occurrence of two TERT promoter mutations (-124C>T and -146C>T) and their potential association with unfavorable clinical features in a large cohort of mPTCs. METHODS: A total of 431 mPTCs cases were collected from six Italian institutions, and TERT promoter mutational status was assessed by a next-generation sequencing approach. RESULTS: TERT promoter mutations were found in 4.7% of the analyzed mPTCs, showing that even microcarcinomas carry mutations in this gene. Correlation analysis showed that TERT promoter mutations are not associated with aggressive features or clinical outcome in the cohort analyzed. CONCLUSIONS: TERT mutations are present but uncommon in mPTCs. Apparently, in mPTCs, the occurrence of TERT mutations is not correlated with unfavorable clinical features

Detection of asymptomatic thyroid nodules has increased. Consensus is lacking regarding the optimal follow-up of cytologically proven benign lesions and sonographically nonsuspicious nodules. Current guidelines recommend serial ultrasound examinations and reassessment of cytology if significant growth is observed.To determine the frequency, magnitude, and factors associated with changes in thyroid nodule size.Prospective, multicenter, observational study involving 992 consecutive patients with 1 to 4 asymptomatic, sonographically or cytologically benign thyroid nodules. Patients were recruited from 8 hospital-based thyroid-disease referral centers in Italy between 2006 and 2008. Data collected during the first 5 years of follow-up, through January 2013, were analyzed.Baseline nodule growth (primary end point) was assessed with yearly thyroid ultrasound examinations. Size changes were considered significant for growth if an increase of 20% or more was recorded in at least 2 nodule diameters, with a minimum increase of 2 mm. Baseline factors associated with growth were identified. Secondary end points were the sonographic detection of new nodules and the diagnosis of thyroid cancer during follow-up.Nodule growth occurred in 153 patients (15.4% [95% CI, 14.3%-16.5%]). One hundred seventy-four of the 1567 original nodules (11.1% [95% CI, 10.3%-11.9%]) increased in size, with a mean 5-year largest diameter increase of 4.9 mm (95% CI, 4.2-5.5 mm), from 13.2 mm (95% CI, 12.1-14.2 mm) to 18.1 mm (95% CI, 16.7-19.4 mm). Nodule growth was associated with presence of multiple nodules (OR, 2.2 [95% CI 1.4-3.4] for 2 nodules; OR, 3.2 [95% CI, 1.8-5.6 for 3 nodules; and OR, 8.9 [95% CI, 4.4-18.0] for 4 nodules), main nodule volumes larger than 0.2 mL (OR, 2.9 [95% CI, 1.7-4.9] for volumes0.2 to1 mL and OR, 3.0 [95% CI, 1.8-5.1] for volumes ≥1 mL), and male sex (OR, 1.7 [95% CI, 1.1-2.6]), whereas an age of 60 years or older was associated with a lower risk of growth than age younger than 45 years (OR, 0.5 [95% CI 0.3-0.9]). In 184 individuals (18.5% [95% CI, 16.4%-20.9%]), nodules shrank spontaneously. Thyroid cancer was diagnosed in 5 original nodules (0.3% [95% CI, 0.0%-0.6%]). Only 2 had grown. An incidental cancer was found at thyroidectomy in a nonvisualized nodule. New nodules developed in 93 patients (9.3% [95% CI, 7.5%-11.1%]), with detection of one cancer.Among patients with asymptomatic, sonographically or cytologically benign thyroid nodules, the majority of nodules exhibited no significant size increase during 5 years of follow-up and thyroid cancer was rare. These findings support consideration of revision of current guideline recommendations for follow-up of asymptomatic thyroid nodules.

Objective: The association between papillary thyroid cancer (PTC) and Hashimoto's thyroiditis is widely recognized, but less is known about the possible link between circulating anti-thyroglobulin antibody (TgAb) titers and PTC aggressiveness. To shed light on this issue, we retrospectively examined a large series of PTC patients with and without positive TgAb. Methods: Data on 220 TgAb-positive PTC patients (study cohort) were retrospectively collected in 10 hospital-based referral centers. All the patients had undergone near-total thyroidectomy with or without radioiodine remnant ablation. Tumor characteristics and long-term outcomes (follow-up range: 2.5–24.8 years) were compared with those recently reported in 1020 TgAb-negative PTC patients with similar demographic characteristics. We also assessed the impact on clinical outcome of early titer disappearance in the TgAb-positive group. Results: At baseline, the study cohort (mean age 45.9 years, range 12.5–84.1 years; 85% female) had a significantly higher prevalence of high-risk patients (6.9% vs. 3.2%, p

The current use of life-long follow-up in patients with papillary thyroid cancer (PTC) is based largely on the study of individuals diagnosed and treated in the latter half of the 20th century when recurrence rates were approximately 20% and relapses detected up to 20-30 years after surgery. Since then, however, diagnosis, treatment, and postoperative monitoring of PTC patients have evolved significantly.The objective of the study was to identify times to PTC recurrence and rates by which these relapses occurred in a more recent patient cohort.We retrospectively analyzed follow-up data for 1020 PTC patients consecutively diagnosed in 1990-2008 in 8 Italian hospital centers for thyroid disease. Patients underwent thyroidectomy, with or without radioiodine ablation of residual thyroid tissue and were followed up with periodic serum thyroglobulin assays and neck sonography.At the initial posttreatment (≤ 12 months) examination, 948 patients had no structural/functional evidence of disease. During follow-up (5.1-20.4 years; median 10.4 years), recurrence (cervical lymph nodes, thyroid bed) was diagnosed in 13 (1.4%) of these patients. All relapses occurred 8 or fewer years after treatment (10 within the first 5 years, 6 within the first 3 years). Recurrence was unrelated to the use/omission of postoperative radioiodine ablation.In PTC patients whose initial treatment produces disease remission (no structural evidence of disease), recurrent disease is rare, and it usually occurs during the early postoperative period. The picture of recurrence timing during the follow-up provides a foundation for the design of more cost-effective surveillance protocols for PTC patients.

Contains fulltext : 125462.pdf (Publisher’s version ) (Closed access) Objectives: To evaluate the diagnostic accuracy of fine-needle aspiration biopsy (FNAB) to preoperatively diagnose medullary thyroid cancer (MTC) among multiple international centers and evaluate how the cytological diagnosis alone could impact patient management.Methods: We performed a retrospective chart review of sporadic MTC (sMTC) patients from 12 institutions over the last 29 years. FNAB cytology results were compared to final pathologic diagnoses to calculate FNAB sensitivity. To evaluate the impact of cytology sensitivity for MTC according to current practice and to avoid confounding results by local treatment protocols, changes in treatment patterns over time, and the influence of ancillary findings (e.g., serum calcitonin), therapeutic interventions based on FNAB cytology alone were projected into 1 of 4 treatment categories: total thyroidectomy (TT) and central neck dissection (CND), TT without CND, diagnostic hemithyroidectomy, or observation.Results: A total of 313 patients from 4 continents and 7 countries were included, 245 of whom underwent FNAB. FNAB cytology revealed MTC in 43.7% and possible MTC in an additional 2.4%. A total of 113 (46.1%) patients with surgical pathology revealing sMTC had FNAB findings that supported TT with CND, while 37 (15.1%) supported TT alone. In the remaining cases, diagnostic hemithyroidectomy and observation were projected in 32.7% and 6.1%, respectively.Conclusion: FNAB is an important diagnostic tool in the evaluation of thyroid nodules, but the low sensitivity of cytological evaluation alone in sMTC limits its ability to command an optimal preoperative evaluation and initial surgery in over half of affected patients.

Serum thyroglobulin (Tg) assays are considered fundamental in postoperative surveillance of differentiated thyroid cancer (DTC) patients. However, the postsurgical profile of Tg levels has never been specifically investigated in patients who do not undergo radioiodine remnant ablation (RRA).Our objective was to explore the evolution of Tg levels over time in DTC patients treated with total or near-total thyroidectomy without RRA.We retrospectively analyzed 290 consecutively diagnosed cases of low-risk (American Thyroid Association criteria) DTC treated with thyroidectomy alone and followed yearly with neck ultrasonography and serum Tg assays. We compared final Tg values in this group and a matched group of 495 RRA-positive patients. Temporal trends of serial Tg levels were also analyzed in 78 of the RRA-negative patients monitored with a high-sensitivity immunoradiometric assay.After follow-up of 2.5-22 yr (median 5 yr), final Tg levels were undetectable (1 ng/ml) in 274 of 290 RRA-negative patients (95%) and 492 of 495 RRA-positive controls (99%). In the subset of 78 RRA-negative patients, undetectable Tg levels (0.2 ng/ml) were recorded in 60% at the first postoperative evaluation (3-12 months) and in 79% after 5 yr. Tg levels increased in the single patient who experienced disease recurrence during the observation period.In most RRA-negative patients, postoperative serum Tg values spontaneously drop to undetectable levels within 5-7 yr after thyroidectomy. Thus, in later phases, Tg assays may be a valuable tool for follow-up even in patients who do not undergo RRA.

Administration of radioiodine (I(131)) is currently exploited for both diagnostic and therapeutic treatment of thyroid cancer. Few data are available on the sodium/iodide symporter (NIS) expression in human testis, a particular important prerequisite to predict radioiodine accumulation in the gonads of males with thyroid cancer exposed to such a treatment. In this study, we analyzed the expression of NIS in mouse, rat and human normal testis in different stages of development. By using a quantitative RT-PCR, Western blot and immunohistochemical analysis, NIS mRNA and protein were measured in both fetal and adult testicular tissues. NIS transcript was detected in both fetal and adult testis, although its expression levels were approximately 10-fold less than in thyroid gland. Western blot analysis and immunohistochemistry showed the presence of NIS protein in germinal and Leydig cells, but not in Sertoli cells with prevalent expression in the cytosol compartment of the cells. Our study demonstrates that NIS transcript and protein are expressed in normal testis. Further studies will demonstrate whether it may act as the transporter of radioiodine in normal testis of male patients with thyroid cancer.

Context In multiple endocrine neoplasia (MEN), rearranged during transfection (RET), gene testing has been extensively exploited to characterize tumour aggressiveness and optimize the diagnostic and clinical management. Objective To report the underlying genetic alterations in an unusual case of MEN type 2 (MEN-2A). Design and patient Occult medullary thyroid carcinoma (MTC) was diagnosed in a 44-year-old man who had presented with unilateral phaeochromcytoma. DNA extracted from the blood and tumour tissues was analysed for mutations in RET. The transforming potential and mitogenic properties of the identified RET mutation were investigated. Results The patient carried a novel heterozygous germ-line RET mutation in exon 5 (Val292Met, GTG>ATG) (V292M/RET) with no evidence of additional somatic alterations. The mutation maps to the third cadherin-like domain of RET, which is usually not included in RET screening. Interestingly, MTC with concomitant phaeochromcytoma has never been associated with a RET mutation involving the extracellular cadherin-like domain. V292M/RET was absent in the only two relatives examined. In vitro assays indicate that the mutant has low-grade transforming potential. Conclusions Complete characterization and classification of all novel RET mutations are essential for extending genetic analysis in clinical practice. Our findings suggest that: (i) in all MEN-2 patients negative for RET hot-spot mutations, testing should be extended to all coding regions of the gene and (ii) the newly identified V292M/RET mutation is characterized by relatively weak in vitro transforming ability.

Thyroglobulin (Tg) assay of material from fine-needle aspiration of neck masses can help distinguish neck masses of thyroid origin from other masses. We describe its utility in a patient with an unusual constellation of findings, a neck lump identified as a lymph node metastasis from a contralateral occult papillary thyroid carcinoma (PTC).A 56-year-old woman was referred to our center for evaluation of a 15-mm right lateral cervical neck mass which was strongly hypoechoic, not homogenous and contained several microcalcifications. There was no family history of thyroid disease, the patient was euthyroid and was not taking medications for thyroid disorders. On physical examination the thyroid was slightly enlarged and was normal on ultrasound except for a 1 x 3 mm hypoechoic nodule in the middle of the left lobe. Ultrasound-guided fine-needle aspiration biopsy (FNAB) of the right lateral cervical mass was performed with the Tg concentration of the FNAB washout liquid being300 ng/mL and the cytology showing lymphoid elements mixed with polymorphous epithelial cells with atypical nuclei, suggesting lymph node metastasis from a cancer of epithelial origin. A lymph node metastasis from a papillary thyroid microcarcinoma (micro-PTC) was the presumptive diagnosis with the preoperative staging being Tx N1b. The patient underwent total thyroidectomy and bilateral lymph node dissection. At pathology, the right cervical mass was confirmed as lymph node metastasis of a PTC, and a unifocal micro-PTC was found in the middle left lobe. The patient was readmitted for a therapeutic (131)I dose (4810 MBq). At the time of (131)I administration, the whole-body scan showed only minimal thyroid bed uptake and serum Tg was1 ng/mL. She was maintained on l-thyroxine treatment (150 microg/d). Five year later she did not have evidence of recurrent or residual PTC.We describe the first case of contralateral lymph node metastasis from a unifocal micro-PTC identified by the detection of high Tg levels in the wash-out liquid of FNAB.

Active iodine prophylaxis in Italy was limited before 2005. Thus, endemic goiter, as well as other iodine deficiency disorders (IDD), have been documented in the country, mainly in southern and central Italy. Calabria is a southern region in Italy, where foci of endemic goiter have been occasionally described. During the years 1990–1996, a systematic screening for the characterization of iodine deficiency in the region was performed by evaluating the distribution of the prevalence of goiter in schoolchildren, neonatal TSH results obtained from the congenital hypothyroidism screening program, and urinary iodine excretion values. The European Community, in collaboration with the Italian government, has funded a program for the eradication of IDD in central and southern Italy that started in 1998. The neonatal TSH results from the hypothyroidism screening programs allow the monitoring of iodine deficiency on a population basis, allowing analysis of the territory according to iodine supply. Preliminary data obtained from the congenital hypothyroidism screening program in Calabria suggest that iodine supply is progressively improving in southern Italy since the year 1999. All parameters employed unequivocally indicated that moderate iodine deficiency is present in the inland region, with pockets of severe iodine deficiency in some villages. In the coastal areas, iodine supply varied from sufficient to marginally low, while mild iodine deficiency was found in a major town located at sea level.

An elevated serum calcitonin level is a highly sensitive marker for medullary thyroid carcinoma (MTC) that can be used for screening, differential diagnosis, prognostic assessment, follow-up monitoring, and assessment of treatment response. Nevertheless, additional data are required to definitively support routine measurement of calcitonin levels in the initial work-up of patients with thyroid nodules, mainly because there is no convincing evidence that such testing actually reduces MTC-related mortality. By contrast, the prognostic value of measuring calcitonin levels preoperatively, postoperatively, and during follow-up of patients with MTC is widely acknowledged. Furthermore, determination of calcitonin levels is also used to evaluate the response of MTC to novel forms of systemic treatment, such as tyrosine kinase inhibitors. In this Review, we discuss the key issues surrounding the use of this laboratory test in the clinical management of patients with MTC.

Thyroid hormone binding autoantibodies have been observed in serum from patients affected by either thyroid disorders or autoimmune nonthyroid diseases.ln most instances, no major involvement of thyroid status of these patients has been reported. However, some authors have attributed the occurrence of hypothyroidism to high capacity thyroid hormone binding autoantibodies.In order to verify such a hypothesis, the effect of these autoantibodies on serum TSH and liver mitochondrial alpha-glycerophosphate dehydrogenase has been investigated in rats, wherein circulating T3-binding antibodies (max cap10−12 10−8 to mol/l) were induced by active immunization.Starting from the 3rd week after antigen injection, the binding of 125I-T3 to serum immunoglobulins was progressively increased, with a peak at the 5th week. In immunized animals considered as a whole group, serum TSH levels were significantly higher and liver mitochondrial alpha-glycerophosphate dehydrogenase activity was significantly lower than in normal rats (m ± SE: 145 ± 15 vs 34 ± 2 ng/dl and 0.0450 ± 008 vs 0.0980 ± 005 ΔA. mg/prot/.min, respectively; p < 0.001) The pattern of both TSH increase and alpha-glycerophosphate dehydrogenase decrease were similar to the evolution of 125-I-T3 binding to serum immunoglobulins, the maximal TSH values and lowest enzyme levels being observed at the 5th week after the beginning of the experiment. These results indicate that high capacity thyroid hormone binding autoantibodies may actually reduce thyroid hormone disposal at cellular level, at least prior to the attainment of steady state T3- antibody hormone binding.

The rate of liver mitochondrial alpha-glycerophosphate dehydrogenase (GPD) induction was compared to the suppression of pituitary thyrotropin (TSH) secretion in thyroidectomized rats submitted to prolonged administration of small amounts of L-thyroxine (T4). With both 350 and 530 ng T4/100 g bw/day, liver alpha-GPD activity remained at post-thyroidectomy level (mean +/- SE: 0.030 +/- 0.002 and 0.034 +/- 0.001 delta A/mg prot/min, respectively) throughout all experiment. A sharp increase in enzyme activity was observed after 3 weeks of treatment in rats receiving 715 ng T4 / 100 g bw / day (mean +/- SE: 0.086 +/- 0.003 delta A/mg prot/min). In contrast, serum TSH levels were lower than pretreatment values (199 +/- 8ng/dI) in rats receiving 350 ng T4/100 g bw/day (mean +/- SE: 104 +/- 15 ng/dI; t = 7.48, p less than 0.001), decreased progressively with increasing T4 doses (m +/- SE:530 ng T4/100 g/day = 36 +/- 7 ng/dI); after only 48 h of treatment and were not significantly modified thereafter. The data are in agreement with the hypothesis of a nonlinear relationship between the degree of thyroid hormone receptor occupancy and the rate of liver mitochondrial alpha-GPD induction.

OBJECTIVE: Nonfunctioning thyroid nodules (NFTNs) display a diminished iodide-concentrating ability, owing to defective expression and cell membrane targeting of the sodium-iodide symporter (NIS). Since NIS expression is primarily modulated by thyroid iodine content in vitro and in animal models, we attempted to determine whether iodine supply influences the expression and localization of human NIS (hNIS) in NFTNs. DESIGN: Using immunohistochemistry, we analyzed cold hyperplastic nodules and nonnodular thyroid samples (controls) from patients living in iodine-sufficient (n = 19) or severely iodine-deficient (n = 15) areas. MAIN OUTCOME: Nodules from the iodine-sufficient area exhibited weak or absent hNIS immunostaining whereas almost all nodules from the iodine-deficient area were hNIS positive. Heterogeneous hNIS staining was common among the iodine-deficient samples (p = 0.028). hNIS was localized on membrane in all nodular samples from the iodine-deficient area and in less than 40% in the iodine-sufficient area. CONCLUSIONS: hNIS is adequately expressed and appropriately localized in NFTNs cell membrane from iodine-deficient areas and its expression in vivo is modulated by iodine supply.

Persistent or recurrent disease is rare in low risk patients with papillary thyroid cancer, and follow-up of these patients is a matter of debate. Neck ultrasonography (US), serum thyroglobulin (Tg), and whole body scan (WBS) after T(4) withdrawal were performed in 456 patients, followed up to 5 yr. At the end of the first year, 335 patients were Tg negative, and 121 were Tg positive; 65 of 96 patients with Tg levels between 1 and 10 ng/ml became spontaneously Tg negative after 2 yr. During follow-up, WBS discovered node metastases in 13 subjects, and US discovered node metastases in 38 subjects (31 Tg positive and 7 Tg negative). WBS did not add any information, because all WBS-positive patients were also US and Tg positive. Fifty percent of metastases were less than 1 cm and not palpable. Finally, the negative predictive value of both negative Tg and US at first follow-up was 98.8%. We suggest a first follow-up based upon US assessment and stimulated (after T(4) withdrawal or recombinant human TSH) serum Tg determination; subsequently, 1) US should not be mandatory at each examination in initially Tg- and US-negative subjects, but is strongly suggested in all other cases; 2) Tg determination should be repeated 1 yr later, after exogenous or endogenous TSH stimulation only in initially Tg-positive patients without any other evidence of residual disease; and 3) Tg measurement during therapy should be sufficient in all other cases.

The distribution of goiter prevalence in schoolchildren (no.=13,984, age 6-14 yr), the neonatal TSH results obtained from the congenital hypothyroidism screening program and the urinary iodine excretion values (no.=284) were employed for the assessment of iodine deficiency in Calabria, a Southern Italy region. Data were collected during the years 1990-1996. In the inland territory, goiter prevalence ranged from 19 to 64%. At sea level, there was a great variability of goiter prevalence, with values varying from 5.3 to 25.7%. The analysis of the neonatal hypothyroidism screening program data (no.=21,078) showed a 14.8% frequency of TSH levels5 microU/ml whole blood in newborns from the inland territory and a 14.1% frequency at sea level. Urinary iodine excretion resulted (mean+/-SD) 53.8+/-43.4 microg/l (range:20 to 189 microg/l) in the inland territory and 89.6+/-59.8 microg/l (range: 26 to 333 microg/l) at sea level. Median urinary iodine excretion values in 13 villages or small towns of the inland territory ranged from 31 to 57 microg/l. In 2 major towns located at sea level, the median iodine excretion values were 72 microg/l in Crotone main city and 94 microg/l in Reggio Calabria main city. The data indicated that moderate, with pockets of severe iodine deficiency is present in the inland region while iodine supply varies from sufficient to marginally low in the coastal areas. Mild iodine deficiency was found in a major town located at sea level.

A 62-year-old woman presented abdominal pain and a rightsided pelvic mass. Ultrasonography showed a large, thickwalled, cystic ovarian mass with solid components. The patient underwent laparotomic monolateral annessectomy. Histology showed an endometriosic cyst, with a 17-cm struma ovarii containing a 3-mm single papillary thyroid carcinoma. Pelvic ultrasonography showed a normal left ovary, abdomino-pelvic CT scan showed only two renal cysts. The patient had no previous history of thyroid disease. Thyroid evaluation showed a 12 9 17 mm hypoechoic nodule with benign

Clinical investigation of enlarged, local lymph nodes after surgery for papillary thyroid carcinoma is problematic. Use of the fine-needle aspiration thyroglobulin assay could help to identify patients whose disease has progressed to lymph-node metastasis.

Thyroid nodules presenting as hot at 131I-scintigraphy are usually benign follicular adenomas. We report a 42-year-old female patient with an autonomously functioning Hürthle cell thyroid carcinoma causing thyrotoxicosis. Genetic analysis of her thyroid tumoral DNA revealed a heterozygotic activating mutation of the thyrotropin receptor (TSHR) gene that was located downstream to all of the other genetic alterations currently identified, and is due to a base substitution at codon 677 (normal cytosine replaced by guanine, CTG for GTG causing leucine substitution by valine in the seventh transmembrane domain of the receptor). This mutation was detected in the tumor, but not in the leucocytes from the same patient. The Val 677-TSHR mutant showed constitutive activity, in terms of cyclic adenosine monophosphate (cAMP) production, when permanently transfected in Chinese hamster ovary (CHO) cells. Gsp and ras oncogenes and the p53 tumor suppressor gene were not present in the Hürthle cell cancer. The TSHR mutation in this Hürthle cell carcinoma may be responsible for maintaining differentiated thyroid function and hyperthyroidism.

Fc epsilon receptor (CD23)-mediated capture of IgE-antigen complexes by B cells provides a powerful antigen presenting system. Our goal was to develop a system using high affinity, human, organ-specific monoclonal autoantibodies for antigen capture by B cells. For this purpose, we converted a recombinant human autoantibody to TPO from a Fab (SP1.4) to an IgE molecule. Sera from all patients with autoimmune thyroid disease contain autoantibodies with the same epitope as SP1.4. The SP1.4 H and L chain V region genes were spliced by overlap PCR to a mammalian, non-immunoglobulin signal peptide and transferred to expression vectors for human IgG1 and kappa, respectively. After inserting the IgE constant region genes into the H chain vector, the kappa and IgE H chain vectors were expressed in SP2/0 cells. SP1.4-IgE retains its high affinity (Kd) for TPO (approximately 2 x 10(-10) M), recognizes the same epitope as Fab SP1.4 and, importantly binds to a different epitope than does Fab TR1.9. Binding of preformed complexes of SP1.4-IgE and biotinylated TPO to EB virus transformed B cells (EBVL) was weakly detectable by flow cytometry and was displaced by unlabeled TPO. SP1.4-IgE/125I-TPO complex binding to EBVL was much more clearly evident, was also inhibited by the addition of unlabeled TPO, and was greatly reduced by preincubation of the EBVL with anti-CD23. Further, autologous EBVL preincubated with SP1.4-IgE/TPO complexes stimulated proliferation of TPO-specific T cells. IgE autoantibody-mediated antigen focusing to B cells is unlikely to operate in vivo but is, instead, a powerful investigative tool. In conclusion, SP1.4-IgE is the first monoclonal human autoantibody to be developed for IgE-mediated antigen presentation to T cells by EBVL. Recombinant human autoantibodies converted to IgE, possibly in combinations if their epitopes permit simultaneous binding to the same molecule, provide a unique system to generate human T cell lines and clones specific for peptides naturally processed from internalized high affinity autoantibody/autoantigen complexes.

Thyroid hormones (TH) have been shown to exert a direct stimulatory effect on the Ca++-dependent ATPase from human and other mammalian erythrdcytes. In this in vitro system, T4 has been shown to be more effective than T3. In the present study, TH effects on Ca++-dependent ATPase were investigated, using rabbit and human erythrocyte membranes, after preincubation with 10−10M T4, in the presence or in the absence of exogenous calmodulin (CaM) (5.10−12M to 5.10−9 M). Ca++-dependent ATPase activity was measured as inorganic phosphate (Pi) release from 1 mM ATP. The results showed that basal Ca++-dependent ATPase activity in rabbits was moderately increased by T4 (1.44 ± 0.05 vs 1.32 ± 0.04 μmol Pi/mg protein/90 min, mean ± SE; p

Serum concentrations of T4, T3, reverse T3 (rT3), TSH, Thyroxine binding globulin (TBG) and Thyroxine binding prealbumin (TBPA) were measured and a TRH-stimulation test was performed in 10 iodide untreated children affected by cystic fibrosis (CF) and in 84 controls. As compared to the controls, CF patients had lower T4 and rT3, similar T3 and TBG and increased T3:T4 ratios. They also had lower TBPA, but this could not account for the low T4. Finally they had higher basal and TRH-stimulated TSH. Our results indicate subclinical hypothyroidism in CF. The mechanisms responsible for this situation are not elucidated by our data.

This paper describes the identification of circulating autoantibodies to thyroid hormones in 5 patients with Graves’ disease (n = 2), Hashimoto’s thyroiditis (n = 1), primary myxedema (n = 1) and Sjogren syndrome (n = 1) out of 351 individuals. The 351 patients suffered from different autoimmune thyroid disorders, thyroid cancer or lymphoreticular system disorders as well as autoimmune non thyroid illnesses. Immunoglobulin G (IgG) binding of one or both tracer thyroid hormones and in one case also of reverse triiodothyronine, was demonstrated by radioimmunoprecipitation experiments and by reverse flow zone electrophoresis or cellulose acetate electrophoresis and autoradiography. In all cases the binding of radiolabeled thyroid hormones to IgG was displaced by an excess of the respective non radioactive thyroid hormone. Thyroglobulin displaced the binding in 2 cases but preadsorption with human thyroglobulin was ineffective in other 2 cases. Radioimmunoelectrophoresis and autoradiography of the Immunoelectrophoresis plates indicated that in 2 cases the light chains involved in the binding were k chains of the G3 subclass and to a lesser extent of the G1 subclass, in another case they were λ chains and therefore of restricted heterogeneity. In a case of myxedema coma IgG were polyclonal (k and λ chains of the G1 > G2 > G3 subclasses). The thyroxine (T4) or triiodothyronine (T3) antibodies interfere with the hormone measurement in unextracted serum by falsely lowering their concentrations when non specific separation methods are used and raising their concentrations when double antibody radioimmunoassays are used.In one serum containing anti-T4 antibodies, the association constant (Ka) was 0.63 × 106 l/M and absolute binding (Ab0) was1.54 x10-7 l/M. In another serum with anti-T3 IgG, Ka was 4.44 × 107 l/M and Abo 6.22 × 10-9 l/M. In the case of myxedema coma Ka ranged between 3.1 and 4.3 × 108 l/M.

In order to verify the hypothesis of the presence of IgM (or an IgM-like substance) capable of inhibiting thyroid hormone binding to serum proteins and, therefore, capable of enhancing serum free thyroid fractions in non-thyroid illnesses (NTI), we measured TBG and TBPA maximum binding capacities and TBG concentration by an immunoradiometric system in normal pooled sera (NPS) before and after enrichment with purified immunoglobulins (IgM and IgG) from euthyroid NTI sera (free T4, free T3 and TSH levels were normal). A known amount of TBG was diluted 1:2–1:6 with deionized water or with IgM from NPS or from each of 6 NTI sera; the measured values were not different from these expected on theoretical grounds. Likewise, IgM or IgG from normal or from each of 7 NTI sera failed to modify both TBG and TBPA capacities of different NPS, and NTI immunoglobulins showed no binding activity directed to [125I]T4, [125I]T3 or [125I]TBG. In addition, no inhibitory influence of TBG and TBPA capacities was observed when the whole euglobulin fraction obtained by precipitating the same 7 NTI sera by PEG was mixed with NPS. On the other hand, a significant IgM inhibitory effect on the binding of labelled T4 to TBG was found, only when IgM concentrations were experimentally rendered 41 times greater than that requested in the working mixtures. We conclude that no immunoglobulin inhibitor of thyroid hormone binding to transport proteins was evident in the NTI sera investigated.

A 30-yr-old woman with allergic rhinitis and multinodular goiter developed atopic manifestations on different desiccated thyroid extract treatment. Urticaria was observed when the patient was on L-T4 treatment; no atopy was experienced during L-T3 regimen. Serum total immunoglobulin E (IgE) concentration was 390 +/- 7kU/liter (mean +/- SD) prior to any treatment and rose to 850 +/- 7.5 kU/liter when the patient developed urticaria, but declined to baseline figures while she was on L-T3. Intracutaneous testing was positive for desiccated pork thyroid powder, L-T4 and D-T4, but negative for L-T3, DIT and L-tyrosine. Immunoradioligand analyses of mixtures of patient's serum or precipitated immunoglobulin fraction and of 125I-T4 or of 125I-T3 revealed binding of radiolabeled thyroxine to the patient's serum IgE, in turn bound to anti-human-IgE serum covalently coupled to paper discs. This binding was completely inhibited by the preincubation of immunoglobulin fraction with excess unlabeled L-T4 and D-T4, but not with excess nonradioactive L-T3, thus proving the specificity of the binding. Preadsorption experiments performed with desiccated pork thyroid powder solution mixed with the patient's immunoglobulin fraction suggested binding of some unknown component(s) of desiccated thyroid which was apparently not thyroglobulin. This study provides evidence of IgE antibodies to L-T4 cross reacting with D-T4 and capable of binding 125I-T4 in serum. It also suggests a model for the detection of circulating IgE antibodies to thyroid hormones.

Thyroxine-binding globulin (TBG) is the major thyroid hormone carrier protein. The molecule contains approximately 10 sialic acid residues which play a key role in the peripheral metabolism of TBG. Since the serum of patients with liver disease often contains large amounts of several desialylated glycoproteins, the aim of the present studies was to characterize circulating TBG and to examine the possible presence of desialylated TBG (dTBG) in 24 patients with a variety of hepatobiliary diseases and selected on the basis of elevated serum levels of desialylated glycoproteins. Using 4 immunochemical techniques applied for the measurement of TBG, for the detection of dTBG and for the characterization of TBG microheterogeneity, the results indicated: a) a wide scatter of serum TBG levels between 4 and 23 mg/l; b) the absence of detectable amounts of dTBG in any of the sera tested; and c) a close similarity between the microheterogeneity of TBG in patients with liver disease with that of control sera or of purified TBG. In conclusion, in patients with acute and chronic liver disease, TBG, although quantitatively modified, remains qualitatively unaltered, suggesting that diseased liver produces fully sialylated TBG and that its catabolism is not impaired.