Single cell transcriptomic analysis of Graves' disease thyroid glands reveals the broad immunoregulatory potential of thyroid follicular and stromal cells and implies a major re-interpretation of the role of aberrant HLA class II expression in autoimmunity

The study of the immune response in thyroid autoimmunity has been mostly focused on the autoantibodies and lymphocytes, but there are indications that intrinsic features of thyroid tissue cells may play a role in disrupting tolerance that needs further investigation. The overexpression of HLA and adhesion molecules by thyroid follicular cells (TFC) and our recent demonstration that PD-L1 is also moderately expressed by TFCs in autoimmune thyroid indicates that TFCs they may activate but also inhibit the autoimmune response. Intriguingly, we have recently found that in vitro cultured TFCs are able to suppress the proliferation of autologous lymphocyte T in a contact-dependent manner which is independent of the PD-1/PD-L1 signaling pathway. To get a more comprehensive picture of TFC activating and inhibitory molecules/pathways driving the autoimmune response in the thyroid glands, preparations of TFCs and stromal cells from five Graves' disease (GD) and four control thyroid glands were compared by scRNA-seq. The results confirmed the previously described interferon type I and type II signatures in GD TFCs and showed unequivocally that they express the full array of genes that intervene in the processing and presentation of endogenous and exogeneous antigens. GD TFCs lack however expression of costimulatory molecules CD80 and CD86 required for priming T cells. A moderate overexpression of CD40 by TFCs was confirmed. GD Fibroblasts showed widespread upregulation of cytokine genes. The results from this first single transcriptomic profiling of TFC and thyroid stromal cells provides a more granular view of the events occurring in GD. The new data point at an important contribution of stromal cells and prompt a major re-interpretation of the role of MHC over-expression by TFC, from deleterious to protective. Most importantly this re-interpretation could also apply to other tissues, like pancreatic beta cells, where MHC over-expression has been detected in diabetic pancreas.

Thyroid cells from normal and autoimmune thyroid glands suppress T lymphocytes proliferation upon contact revealing a new regulatory inhibitory type of interaction independent of PD1/PDL1

Immune Checkpoint Receptors include a number of inhibitory receptors that limit tissue damage during immune responses; blocking PD-1/PD-L1 checkpoint receptor axis led to a paradigm shift in cancer immunotherapy but also to autoimmune adverse effects, prominently thyroid autoimmunity. Although PD-L1 is known to be expressed on thyroid follicular cells (TFCs) of autoimmune glands the role on PD-1/PD-L1 in the interaction between T cells and thyroid cells in the tissue has not been investigated. Here we report that autologous primary TFCs, but not transformed TFCs, inhibit CD4 and CD8 T cell proliferation but no cytokine production. This effect is not, however, mediated by PD-1/PD-L1 nor locally produced cytokines. Beta galactosidase analysis excluded culture-induced senescence as an explanation. High resolution flow cytometry demonstrated that autologous TFC/T cells co-culture induced the expansion of several clusters of double negative (DN) T cells characterized by high expression of activation markers and negative immune checkpoints. Single cell transcriptomic profiling demonstrated that dissociated TFC express numerous candidate molecules for mediating this suppressive activity, including CD40, E-Cadherin and TIGIT ligands. These ligands directly or through the generation of a suppressor population of DN T cells, and not the PD-1/PD-L1 axis, are most likely the responsible of TFC immunosuppressive activity. These results contribute to reveal the complex network of inhibitory mechanism that operate at the tissue level to restrain autoimmunity but also point to pathways, other that PD-1/PD-L1, that can contribute to tumor evasion.

Initial clinical and treatment patterns of advanced differentiated thyroid cancer: ERUDIT study

Background

Up to 30% of differentiated thyroid cancer (DTC) will develop advanced-stage disease (aDTC) with reduced overall survival (OS).

Objective

The aim of this study is to characterize initial diagnosis of aDTC, its therapeutic management, and prognosis in Spain and Portugal.

Methods

A multicentre, longitudinal, retrospective study of adult patients diagnosed with aDTC in the Iberian Peninsula was conducted between January 2007 and December 2012. Analyses of baseline characteristics and results of initial treatments, relapse- or progression-free survival ((RP)FS) from first DTC diagnosis, OS, and prognostic factors impacting the evolution of advanced disease were evaluated.

Results

Two hundred and thirteen patients (median age: 63 years; 57% female) were eligible from 23 hospitals. Advanced disease presented at first diagnosis (de novo aDTC) included 54% of patients, while 46% had relapsed from early disease (recurrent/progressive eDTC). At initial stage, most patients received surgery (98%) and/or radioiodine (RAI) (89%), with no differences seen between median OS (95% CI) (10.4 (7.3-15.3) years) and median disease-specific-survival (95% CI) (11.1 (8.7-16.2) years; log-rank test P = 0.4737). Age at diagnosis being <55 years was associated with a lower risk of death (Wald chi-square (Wc-s) P < 0.0001), while a poor response to RAI to a higher risk of death ((Wc-s) P < 0.05). In the eDTC cohort, median (RP)FS (95% CI) was of 1.7 (1.0-2.0) years after RAI, with R0/R1 surgeries being the only common significant favourable factor for longer (RP)FS and time to aDTC ((Wc-s) P < 0.05).

Conclusion

Identification of early treatment-dependent prognostic factors for an unfavourable course of advanced disease is possible. An intensified therapeutic attitude may reverse this trend and should be considered in poor-performing patients. Prospective studies are required to confirm these findings.

Lymphocytic Thyroiditis Transcriptomic Profiles Support the Role of Checkpoint Pathways and B Cells in Pathogenesis

Background: Autoimmune thyroid diseases are the most common types of autoimmune diseases, but their physiopathology is still relatively unexplored. Genotype-tissue expression (GTEx) is a publicly available repository containing RNAseq data, including profiles from thyroid. Approximately 14.8% of these glands were affected by focal lymphocytic thyroiditis and 6.3% were annotated as Hashimoto. We interrogated these data to improve the characterization of infiltrating cells and to identify new molecular pathways active in autoimmune thyroiditis. Materials and Methods: Histological GTEx images of 336 thyroid samples were classified into three categories, that is, non-infiltrated thyroid, small focal infiltrated thyroid, and extensive lymphoid infiltrated thyroid. Differentially expressed genes among these categories were identified and subjected to in silico pathway enrichment analysis accordingly. CIBERSORTx deconvolution was used to characterize infiltrating cells. Results: As expected, most of the transcriptional changes were dependent on tissue infiltration. Upregulated genes in tissues include-in addition to lineage-specific B and T cell genes-a broad representation of inhibitory immune checkpoint receptors expressed by B and T lymphocytes. CIBERSORTx analysis identified 22 types of infiltrating cells showed that T cells predominate 3:1 over B cells in glands with small infiltrates, only by 1.7:1 in those with large infiltrates. Follicular helper and memory CD4 T cells were significantly more abundant in glands with large infiltrates (p < 0.0001), but the most prominent finding in these glands was an almost sixfold increase in the number of naive B cells (p < 0.0001). A predominance of M2 macrophages over M1 and M0 macrophages was observed in the three gland categories (p < 0.001). Conclusions: Analysis of transcriptomic RNA-seq profiles constitutes a rich source of information for the analysis of autoimmune tissues. High-resolution transcriptomic data analysis of thyroid glands indicates the following: (a) in all infiltrated glands, active autoimmune response coexists with suppressor counteracting mechanisms involving several inhibitory checkpoint receptor pairs, (b) glands with small infiltrates contain an unexpected relatively high proportion of B lymphocytes, and (c) in highly infiltrated glands, there is a distinct transcriptomic signature of active tertiary lymphoid organs. These results support the concept that the autoimmune response is amplified in the thyroid tissue.

Validation of dynamic risk stratification and impact of BRAF in risk assessment of thyroid cancer, a nation-wide multicenter study

INTRODUCTION

The dynamic risk stratification (DRS) is a relatively new system in thyroid cancer that considers the response to primary treatment to improve the initial risk of recurrence. We wanted to validate DRS system in a nationwide multicenter study and explore if the incorporation of BRAFV600E into DRS helps to better categorize and predict outcomes.

MATERIALS AND METHODS

Retrospective study of 685 patients from seven centers between 1991 and 2016, with a mean age of 48 years and a median follow-up time of 45 months (range 23-77). The overall BRAFV600E prevalence was 53.4%. We classified patients into four categories based on DRS ('excellent', 'indeterminate', 'biochemical incomplete', and 'structural incomplete' response). Cox regression was used to calculate adjusted hazard ratios (AHR) and proportions of variance explained (PVEs).

RESULTS

We found 21.6% recurrences and 2.3% cancer-related deaths. The proportion of patients that developed recurrence in excellent, indeterminate, biochemical incomplete and structural incomplete response to therapy was 1.8%, 54%, 91.7% and 96.2% respectively. Considering the outcome at the end of the follow up, patients showed no evidence of disease (NED) in 98.2, 52, 33.3 and 25.6% respectively. Patients in the structural incomplete category were the only who died (17.7%). Because they have similar outcomes in terms of NED and survival, we integrated the indeterminate and biochemical incomplete response into one unique category creating the 3-tiered DRS system. The PVEs of the AJCC/TNM staging, ATA risk classification, 4-tiered DRS, and 3-tiered DRS to predict recurrence at five years were 21%, 25%, 57% and 59% respectively. BRAFV600E was significantly associated with biochemical incomplete response (71.1 vs 28.9%) (HR 2.43; 95% CI, 1.21 to 5.23; p=0.016), but not with structural incomplete response or distant metastases. BRAF status slightly changes the AHR values of the DRS categories but is not useful for different risk grouping.

CONCLUSIONS

This is the first multicenter study to validate the 4-tiered DRS system. Our results also show that the 3-tiered DRS system, by integrating indeterminate and biochemical incomplete response into one unique category, may simplify response to therapy keeping the system accurate. BRAF status does not provide any additional benefit to DRS.

Thyroid disorders associated with immune control point inhibitors

INTRODUCTION

Immune checkpoint inhibitors (ICPI) have improved progression-free survival in several solid tumors. Side effects are related to overstimulation of the immune system. Thyroid dysfunction (TD) is the most common endocrine immune-related adverse event of ICPI.

OBJECTIVE

To describe the clinical presentation and the course of TD in cancer patients treated with ICPI referred to an endocrinology outpatient clinic.

MATERIAL AND METHODS

This was a descriptive, retrospective and multicenter study of patients with TD associated with ICPI in six Spanish hospitals.

RESULTS

120 patients (50.8% women), mean age 60 ± 12 years were included. The initial TD was hypothyroidism in 49% of patients and hyperthyroidism in 51%, with an average of 76 (41-140) and 43 (26-82) days respectively between the onset of ICPI and the analytical alteration. Significantly, the earlier the first analytical determination was, the greater the prevalence of hyperthyroidism. A turnover was observed in 80% of subjects during follow-up, mostly from hyperthyroidism to hypothyroidism. Twenty-one percent received double ICPI therapy. The most frequent form of presentation in monotherapy was hypothyroidism (57%), and in double therapy it was hyperthyroidism (77%) (p = 0.002). Patients under double therapy showed thyroid alterations earlier than those in the monotherapy group (p = 0.001). After a follow-up of 205 (112-360) days, half of the patients continued under levothyroxine treatment.

CONCLUSIONS

Hypothyroidism and hyperthyroidism present in a similar proportion in cancer patients undergoing ICPI therapy. Our results suggest that transitory hyperthyroidism may not be detected in a relevant number of cases. In addition, TD in double therapy presents earlier. This should be taken into account in the follow-up protocols of these patients.

Recovery of parathyroid function in patients with thyroid cancer treated by total thyroidectomy: An analysis of 685 patients with hypoparathyroidism at discharge of surgery

OBJECTIVE

We aimed to study the predictive factors for recovery of parathyroid function in hypoparathyroid patients after total thyroidectomy for thyroid cancer.

METHODS

We designed a retrospective, multicentre and nation-wide analysis of patients with total thyroidectomy who were seen in twenty endocrinology departments from January to March 2018. We selected patients with histologically proven thyroid cancer and retrieved information related to surgical procedure and thyroid cancer features. Survival analysis and Cox regression analysis were used to study the relationship between these variables and the recovery of parathyroid function.

RESULTS

From 685 patients with hypoparathyroidism at discharge of surgery, 495 (72.3%) recovered parathyroid function over time. Kaplan-Meier analysis showed that this recovery was significantly related to the presence of specialized surgical team (P<0.001), identification of parathyroid glands at surgery (P<0.001), papillary histopathology (P=0.040), and higher levels of postoperative calcium (Ca) (P<0.001) and parathyroid hormone (PTH) (P<0.001). Subjects with gross extrathyroidal extension (P=0.040), lymph node metastases (P=0.004), and surgical re-intervention after initial surgery (P=0.024) exhibited a significant risk of persistence of hypoparathyroidism. Multivariate Cox regression analysis showed that the significant and independent factors for recovery of parathyroid function were postoperative concentrations of Ca (P=0.038) and PTH (P=0.049). The presence of lymph node metastases was a negative predictor of recuperation of parathyroid function (P=0.042) in this analysis.

CONCLUSION

In patients with thyroid cancer, recovery of parathyroid function after total thyroidectomy was directly related to postoperative Ca and PTH concentrations, and inversely related to lymph node metastases.

Late Recovery of Parathyroid Function After Total Thyroidectomy: A Case-Control Study

The clinical characteristics of patients with postoperative hypoparathyroidism who recover parathyroid function more than 12 months after surgery have not been studied. We aimed to evaluate whether the intensity of replacement therapy with calcium and calcitriol is related to the late recovery of parathyroid function. We compared the demographic, surgical, pathological, and analytical features of two groups of patients: cases, i. e., late recovery patients (those who recover parathyroid function>1 year after thyroidectomy, n=40), and controls, i. e., patients with permanent hypoparathyroidism (n=260). Replacement therapy with calcium and calcitriol was evaluated at discharge of surgery, 3-6 months, 12 months, and last visit. No significant differences were found in clinical, surgical, pathological, or analytical characteristics between cases and controls. The proportion of cases who required treatment with calcium plus calcitriol at 12 months was significantly lower than that found in controls (p<0.001). Furthermore, daily calcium and calcitriol doses in controls were significantly higher than those in cases at 3-6 months (p=0.014 and p=0.004, respectively) and at 12 months (p<0.001 and p=0.043, respectively). In several models of logistic regression analysis therapy with calcium and calcitriol at 12 months was negatively related to late recovery of parathyroid function. Although delayed recuperation of parathyroid function after total thyroidectomy is uncommon (13%), follow-up beyond 12 months is necessary in patients with postoperative hypoparathyroidism, especially in those whose needs of treatment with Ca and calcitriol are reducing over time.

Rate of non-invasive follicular thyroid neoplasms with papillary-like nuclear features depends on pathologist's criteria: a multicentre retrospective Southern European study with prolonged follow-up

PURPOSE

To determine the rate of non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) in a multi-institutional series from the Iberian Peninsula and describing this NIFTP cohort.

METHODS

Retrospective study of papillary thyroid carcinoma (PTC) or well-differentiated tumours of uncertain malignant potential (WDT-UMP) diagnosed between 2005 and 2015 and measuring ≥5 mm in adult patients from 17 hospitals. Pathological reports were reviewed to determine the cases that fulfil the original criteria of NIFTP and histology was reassessed. Rates were correlated with the number of PTC and its follicular variant (FVPTC) of each institution. Demographic data, histology, management, and follow-up of the reclassified NIFTP cohort were recorded.

RESULTS

A total of 182 cases with NIFTP criteria were identified: 174/3372 PTC (rate: 5.2%; range: 0-12.1%) and 8/19 WDT-UMP (42.1%). NIFTP rate showed linear correlation with total PTC (p: 0.03) and FVPTC (p: 0.007) identified at each centre. Ultrasound findings were non-suspicious in 60.1%. Fine-needle cytology or core biopsy diagnoses were undetermined in 49.7%. Most patients were treated with total thyroidectomy. No case had nodal disease. Among patients with total thyroidectomy, 89.7% had an excellent response evaluated 1 year after surgery. There were no structural persistence or relapses. Five patients showed residual thyroglobulin after 90 months of mean follow-up.

CONCLUSIONS

NIFTP rate is low but highly variable in neighbouring institutions of the Iberian Peninsula. This study suggests pathologist's interpretation of nuclear alterations as the main cause of these differences. Patients disclosed an excellent outcome, even without using the strictest criteria.

Thyroid lobectomy in patients with differentiated thyroid cancer: an analysis of the clinical outcomes in a nationwide multicenter study

Background

Total thyroidectomy is the standard initial surgery for differentiated thyroid carcinoma (DTC), but the extent of the thyroidectomy remains controversial. Thyroid lobectomy (TL) has been widely used in eastern countries; however, its use has not been generalized in western countries, including Spain. Our aims were to analyse the clinical outcome of a multicentre nation-wide cohort of DTC patients treated by TL and to assess the proportion of patients who required completion of the thyroidectomy and who presented disease recurrence.

Methods

We retrospectively analyzed patients who underwent TL for DTC and were followed-up for ≥12 months. We collected demographic, clinical, and histopathological data. Dynamic risk stratification (DRS) was performed at 12 months and at last visit.

Results

One hundred and sixty-four patients (128 women, mean age 50.8 years, median follow-up 45.4 months) from 9 hospitals were included. There were 158 cases of papillary and 6 of follicular thyroid carcinoma (FTC). Remission of the disease (excellent response) was shown in 71.6% of the patients at 12 months and in 74.4% at the end of follow-up. At that time, there were 34 patients (20.7%) with indeterminate response, 6 (3.7%) with biochemical incomplete response, and 2 (1.2%) with structural incomplete response. Completion of the thyroidectomy was necessary in 8 patients (4.9%), but only 3 of them (1.8%) had disease recurrence.

Conclusions

These results, obtained in real clinical practice, suggest that TL is a safe operative option for selected patients with DTC and that the intensity of the treatment must be tailored according to the presurgical tumor-associated risk, in line with a personalized medicine.

Permanent postoperative hypoparathyroidism: an analysis of prevalence and predictive factors for adequacy of control in a cohort of 260 patients

Background

Recent guidelines for the treatment of hypoparathyroidism emphasize the need for long-term disease control, avoiding symptoms and hypocalcaemia. Our aim has been to analyze the prevalence of poor disease control in a national cohort of patients with hypoparathyroidism, as well as to evaluate predictive variables of inadequate disease control.

Methods

From a nation-wide observational study including a cohort of 1792 patients undergoing total thyroidectomy, we selected 260 subjects [207 women and 53 men, aged (mean ± SD) 47.2±14.8 years] diagnosed with permanent hypoparathyroidism. In every patient demographic data and details on surgical procedure, histopathology, calcium (Ca) metabolism, and therapy with Ca and calcitriol were retrospectively collected. A patient was considered not adequately controlled (NAC) if presented symptoms of hypocalcemia or biochemical data showing low serum Ca levels or high urinary Ca excretion.

Results

Two hundred and twenty-one (85.0%) patients were adequately controlled (AC) and 39 (15.0%) were NAC. Comparison between AC and NAC patients did not show any significant difference in demographic, surgical, and pathological features. Rate of hospitalization during follow-up was significantly higher among NAC patients in comparison with AC patients (35.9% vs. 10.9%, P<0.001). Dose of oral Ca and calcitriol were also significantly higher in NAC subjects. In a subgroup of 129 patients with serum parathyroid hormone (PTH) levels available, we found that NAC patients exhibited significantly lower postoperative PTH concentrations than AC patients [median (interquartile range) 3 (1.9-7.8) vs. 6.9 (3.0-11) pg/mL; P=0.009].

Conclusions

In a nation-wide cohort of 260 subjects with definitive hypoparathyroidism, 15% of them had poor disease control. These patients required higher doses of oral Ca and calcitriol, had higher rate of hospitalization during follow-up and showed lower PTH concentrations in the postoperative period.

Early evolutionary divergence between papillary and anaplastic thyroid cancers

Background

Papillary thyroid cancer (PTC) is the most common thyroid carcinoma and exhibits an almost uniformly good prognosis, while anaplastic thyroid cancer (ATC) is less frequent and is one of the most aggressive cancers usually resistant to conventional treatment. Current hypothesis posits that ATC derives from PTC through the progressive acquisition of a discrete number of genomic alterations and implies that the mutational landscape of ATC resembles that of PTC. However, the clinical behaviour of ATC and PTC is radically different. We decided to address the disconnection between the clinical behaviour of ATC and PTC and the proposed model of the progressive development of ATC from PTC.

Patients and methods

We carried out exome sequencing of DNA from 14 ATC specimens including three cases of concomitant ATC and PTC as well as their corresponding normal DNA from 14 patients. The sequencing results were validated using droplet digital PCR. We carried out immunohistochemistry and immunofluorescence studies of the concomitant ATC and PTC cases. In addition, we integrated our sequencing results with the existing TCGA data.

Results

Most of the somatic mutations identified in the ATC component differed from the ones in PTC in the cases of concomitant ATC and PTC. The trunks of the phylogenetic trees representing the somatic mutations were short with long branches. In one case of concomitant PTC and ATC specimens, we observed an infiltration of PTC cells within the ATC component. Moreover, we integrated our results with data obtained from TCGA and observed that the most frequent mutations found in ATC presented high cancer cell fraction values and were significantly different from the PTC ones.

Conclusion

ATC diverge from PTC early in tumour development and both tumour types evolve independently. Our work allows the understanding of the relationship between ATC and PTC facilitating the clinical management of these malignancies.

Prevalence and risk factors for hypoparathyroidism following total thyroidectomy in Spain: a multicentric and nation-wide retrospective analysis

PURPOSE

The prevalence of postoperative hypoparathyroidism has been studied in registries and in surgical series with highly variable and imprecise results. However, the frequency of this hormonal deficiency in the clinical practice of endocrinologists is not known with accuracy. We aimed to assess the prevalence and risk factors of hypoparathyroidism in patients undergoing total thyroidectomy in Spain.

METHODS

We designed a retrospective, multicentre and nation-wide protocol including all patients with total thyroidectomy who were seen in the endocrinology clinic of the participant centers from January to March 2018. Prevalence of hypoparathyroidism was evaluated at discharge of surgery, 3-6 months after surgery, 12 months after surgery and at last visit. Twenty hospitals participated in the study.

RESULTS

Of 1792 patients undergoing total thyroidectomy, 866 (48.3%) developed postoperative hypoparathyroidism at discharge of surgery. Most of them recover parathyroid function over time. Prevalence of hypoparathyroidism at 3-6 months, 12 months and at last visit was 22.9%, 16.7% and 14.5%, respectively. The risk of developing definitive hypoparathyroidism was related to the presence of parathyroid tissue at histology, lymph node dissection, and two-stage thyroidectomy. Patients with thyroid cancer, with higher postoperative calcium levels and treated by expert surgical teams exhibited lower risk of developing permanent hypoparathyroidism.

CONCLUSIONS

Although most patients with postsurgical hypoparathyroidism recover parathyroid function, the prevalence of permanent disease in clinical practice is non negligible (14.5%). Postoperative calcium, extent and timing of surgery, the presence of cancer, expert surgical team, and parathyroid tissue at histology are predictors of permanent hypoparathyroidism.

Correction to: Prevalence and risk factors for hypoparathyroidism following total thyroidectomy in Spain: a multicentric and nation-wide retrospective analysis

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Strategic reflections of the Spanish Society of Endocrinology and Nutrition on the future of the speciality in the period 2018-2022

Endocrine diseases are experiencing an important increase in their prevalence, due to causes of various kinds, including the epidemic of obesity and malnutrition, the aging of the population, but also the effect of endocrine disruptors, among others. On the other hand, new technologies, both in terms of molecular and genetic analysis, image and new therapeutic devices, require that the endocrine professional community in Spain must be in constant training. The connection with patients through their associations, increasingly active, and with the civil society in general, the professional commitment and demand of various social groups for a modern and equitable care, and to carry out research that facilitates the achievement of advances for patients, forces the specialist in endocrinology and nutrition and the Spanish Society of Endocrinology and Nutrition (SEEN) to position themselves and respond to all these challenges. In this document, the SEEN presents its proposals and its strategy until 2022.

Communication between primary care and physician specialist: is it improving?

BACKGROUND AND OBJECTIVE

Efforts have recently been made in Spain to improve the communication model between primary care and specialized care. The aim of our study was to analyze the impact of a change in the communication model between the two areas when comparing a traditional system to a consulting system in terms of satisfaction of general practitioners and the number of patient referrals.

METHODS

A questionnaire was used to assess the point of view on the relations with the endocrinologist team of 20 general practitioners from one primary care center at baseline and 18 months after the implementation of the new method of communication. In addition, we counted the number of referrals during the two periods.

RESULTS

We analyzed 30 questionnaires; 13 before and 17 after the consulting system was established. Consulting system was preferred to other alternatives as a way of communication with endocrinologists. After the consulting system was implemented, general practitioners were more confident in treating hypothyroidism and diabetes. There was a decrease in the number of patient referrals to specialized care from 93.8 to 34.6 per month after implementation of the consultant system.

CONCLUSIONS

The consultant system was more efficient in resolving problems and responding to general practitioners than the traditional system. General practitioners were more confident in self-management of hypothyroidism and diabetes. A very large decrease in the number of patient referrals was observed after implementation of the consultant system.

Expression of YY1 in Differentiated Thyroid Cancer

The transcription factor Yin Yang 1 (YY1) has an important regulatory role in tumorigenesis, but its implication in thyroid cancer has not been yet investigated. In the present study, we have analyzed the expression of YY1 in differentiated thyroid cancer and assessed the association of YY1 expression with clinical features. Expression of YY1 was evaluated in human thyroid cancer cell lines, a series of matched normal/tumor thyroid tissues and in a thyroid cancer tissue microarray, using real-time PCR, Western blot, and/or immunohistochemistry. YY1 was overexpressed in thyroid cancer cells, at transcription and protein levels. A significant increase of YY1 mRNA was also observed in tumor thyroid tissues. Moreover, immunohistochemical analysis of the thyroid cancer tissue microarray revealed that both papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC) present increased YY1 protein levels (48 and 19%, respectively). After stratification by the level of YY1 protein, positive YY1 expression identifies 88% of patients with PTC. The association of YY1 expression with clinicopathological features in PTC and FTC showed that YY1 expression was related with age at diagnosis. Our data indicates for the first time overexpression of YY1 in differentiated thyroid cancer, with YY1 being more frequently overexpressed in the PTC subtype.

Preoperative TSH level and risk of thyroid cancer in patients with nodular thyroid disease: nodule size contribution

BACKGROUND

Many reports have supported the relationship between high preoperative TSH levels and risk of thyroid cancer in nodular thyroid disease (NTD).

OBJECTIVES

We investigated whether TSH levels are related to the risk of differentiated thyroid carcinoma (DTC) in patients who have undergone total thyroidectomy for NTD. The relationship between TSH and size of malignant nodule was investigated. Finally, we assessed whether TSH levels are related to DTC and presence of additional benign nodules.

PATIENTS AND METHODS

A retrospective study of 980 patients was conducted. Variables included age at diagnosis, TSH level, nodule size, gender, final histology (benign versus DTC), and type of malignancy.

RESULTS

Malignancy was present in 261 (26.6%) patients. These patients had higher median TSH levels as compared to those with no malignancy (1.61 mU/L (0.9-2.5) versus 0.9 mU/L (0.3-1.6); p-value<0.001). TSH was higher in patients with DTC in whom the largest nodule was malignant than in patients in whom the largest nodule was benign (1.80 mU/L (1.1-2.6) versus 1.38 mU/L (0.7-2.1) respectively; p-value=0.025). A significant correlation was seen between malignant nodule size and TSH level, but not between TSH levels and size of the largest benign nodule.

CONCLUSIONS

Our study supported an association between preoperative TSH levels and risk of DTC in patients with NTD. There was also a direct relationship between malignant nodule size and TSH levels. By contrast, no relationship was found between the size of benign nodules and TSH levels.

Clinical challenges in the management of isolated GH deficiency type IA in adulthood

Isolated GH deficiency type IA (IGHDIA) is an infrequent cause of severe congenital GHD, often managed by pediatric endocrinologists, and hence few cases in adulthood have been reported. Herein, we describe the clinical status of a 56-year-old male with IGHDIA due to a 6.7 kb deletion in GH1 gene that encodes GH, located on chromosome 17. We also describe phenotypic and biochemical parameters, as well as characterization of anti-GH antibodies after a new attempt made to treat with GH. The height of the adult patient was 123 cm. He presented with type 2 diabetes mellitus, dyslipidemia, osteoporosis, and low physical and psychological performance, compatible with GHD symptomatology. Anti-GH antibodies in high titers and with binding activity (>101 IU/ml) were found 50 years after exposure to exogenous GH, and their levels increased significantly (>200 U/ml) after a 3-month course of 0.2 mg/day recombinant human GH (rhGH) treatment. Higher doses of rhGH (1 mg daily) did not overcome the blockade, and no change in undetectable IGF1 levels was observed (<25 ng/ml). IGHDIA patients need lifelong medical surveillance, focusing mainly on metabolic disturbances, bone status, cardiovascular disease, and psychological support. Multifactorial conventional therapy focusing on each issue is recommended, as anti-GH antibodies may inactivate specific treatment with exogenous GH. After consideration of potential adverse effects, rhIGF1 treatment, even theoretically indicated, has not been considered in our patient yet.

LEARNING POINTS

Severe isolated GHD may be caused by mutations in GH1 gene, mainly a 6.7 kb deletion.Appearance of neutralizing anti-GH antibodies upon recombinant GH treatment is a characteristic feature of IGHDIA.Recombinant human IGF1 treatment has been tested in children with IGHDIA with variable results in height and secondary adverse effects, but any occurrence in adult patients has not been reported yet.Metabolic disturbances (diabetes and hyperlipidemia) and osteoporosis should be monitored and properly treated to minimize cardiovascular disease and fracture risk.Cerebral magnetic resonance imaging should be repeated in adulthood to detect morphological abnormalities that may have developed with time, as well as pituitary hormones periodically assessed.

[Evolutionary endocrinology: a pending matter]

Twenty years have passed since the foundational article of what is now known as evolutionary medicine (EM) was published. This young medical discipline examines, following Darwinian principles, susceptibility to certain diseases and how we react to them. In short, EM analyzes the final cause of the disease from a historical perspective. Over the years, EM has been introduced in various medical areas in very different ways. While it has found a role in some fields such as infectious diseases and oncology, its contribution in other areas has been quite limited. In endocrinology, EM has only gained prominence as a basis for the so-called "diseases of civilization", including diabetes mellitus and obesity. However, many experts suggest that it may have a much higher potential. The aim of this paper is to provide a view about what evolutionary medicine is. Some examples of how EM may contribute to progress of our specialty are also given. There is no doubt that evolution enriches medicine, but medicine also offers knowledge to evolution.

[Usefulness of the immunohistochemical analysis of several molecular markers in the characterization of papillary thyroid carcinoma with initial lymph node metastasis]

INTRODUCTION AND OBJECTIVE

Regional lymph node metastases (LNM) are a common finding in papillary thyroid cancer (PTC). Approximately half of patients have LNM at diagnosis. The aim of this study was to analyze immunohistochemically the combined expression of different PTC-related molecules in order to identify cases with a tendency to show LNM.

PATIENTS AND METHODS

Thirty-five patients were included in the study. The patients were distributed in two groups. Group I included 19 patients with no histological evidence of LNM at diagnosis. Group II included 16 patients with histological evidence of cervical LNM. Samples were stained for RET/PTC, EGFR, p16(INk4a), p21(cip1), p27(kip1), BCL2, and pAKT.

RESULTS

Expression of p21(cip1), p27(kip1), p16(INk4a), Bcl-2, and pAKT showed no differences between the two groups. However, RET/PTC and EGFR expression showed significant differences: in both cases, staining was more frequent in patients with LNM. Simultaneous positivity of RET/PTC and EGFR was a discriminative marker in patients with LNM. Finally, the combination of RET/PTC negative, EGFR negative and p16(INk4a) negative was found in none of the patients with LNM but in nearly half of those in group I.

CONCLUSIONS

Immunohistochemical analysis of several molecular markers could be useful in the phenotypic characterization of PTC. Application of these markers could enhance diagnosis and improve the management of patients with thyroid cancer.