Unraveling the molecular architecture of autoimmune thyroid diseases at spatial resolution.

Autoimmune thyroid diseases (AITD) such as Graves' disease (GD) or Hashimoto's thyroiditis (HT) are organ-specific diseases that involve complex interactions between distinct components of thyroid tissue. Here, we use spatial transcriptomics to explore the molecular architecture, heterogeneity and location of different cells present in the thyroid tissue, including thyroid follicular cells (TFCs), stromal cells such as fibroblasts, endothelial cells, and thyroid infiltrating lymphocytes. We identify damaged antigen-presenting TFCs with upregulated CD74 and MIF expression in thyroid samples from AITD patients. Furthermore, we discern two main fibroblast subpopulations in the connective tissue including ADIRF+ myofibroblasts, mainly enriched in GD, and inflammatory fibroblasts, enriched in HT patients. We also demonstrate an increase of fenestrated PLVAP+ vessels in AITD, especially in GD. Our data unveil stromal and thyroid epithelial cell subpopulations that could play a role in the pathogenesis of AITD.

Indocyanine green (ICG) angiography-guided thyroidectomy: description of surgical technique.

Background: Postoperative hypoparathyroidism is the most common complication after total thyroidectomy and, when becomes permanent, lead to a myriad of clinical symptoms, long-term need of calcium and vitamin D supplementation and negative impact on the patient's health-related quality of life. Any surgical innovation that could reduce complications and improve outcomes of patients undergoing total thyroidectomy deserves to be considered. Angiography-Guided Thyroidectomy has been proposed as a modification of the standard technique of thyroidectomy aimed to identifying the vascular pattern of the parathyroid glands to maximize efforts for preserving functioning glands at the time of operation. Our aim is to provide a technical description of this procedure based on the use of indocyanine green (ICG) angiography to standardize this technique. Methods: The surgical steps that are followed during a total thyroidectomy are modified due to previous visualization of the feeding vessels of the parathyroid glands according to fluorescence of the vascular mapping obtained by ICG angiography prior to thyroidectomy. The first step is to perform an ICG angiography to assess anatomical features of the feeding vasculature of the parathyroid glands, which allows precise surgical dissection for preservation of the glands. Once the viability of the parathyroids has been evaluated angiographically, thyroidectomy is performed in a second step. Conclusions: ICG angiography-guided thyroidectomy may be effective to preserve the largest number of better perfused parathyroid glands, which would contribute to reduce the risk of postoperative and permanent hypoparathyroidism. It can be successfully and safely implemented in thyroid surgery and standardization of the technique is necessary to homogenize this procedure in the future, allowing a better comparation of the results to be published.

Indocyanine green angiography-guided thyroidectomy versus conventional thyroidectomy for preserving parathyroid function: study protocol for a randomized single-blind controlled trial.

Introduction: Angiography with indocyanine green (ICG) fluorescence performed before thyroidectomy would allow identification of the vascularization of parathyroid glands, maximizing efforts for preserving functioning glands intraoperatively. The rationale of the study was based on the hypothesis that showing the vascular pattern of the parathyroid glands by means of ICG angiography before performing the thyroidectomy could prevent permanent hypoparathyroidism. Methods and analysis: We propose a randomized single-blind controlled and multicenter clinical trial to assess the efficacy and safety of ICG angiography-guided thyroidectomy to identify the vascular pattern of the parathyroid glands versus conventional thyroidectomy in patients scheduled for elective total thyroidectomy. Patients will be randomized 1:1 to ICG angiography-guided thyroidectomy (experimental group) or conventional thyroidectomy (control group). Patients in the experimental group will undergo ICG angiography before thyroidectomy to identify the feeding vessels of the parathyroid glands and then, post-thyroidectomy ICG angiography to predict immediate parathyroid gland function by scoring the degree of fluorescence of the glands. Patients in the control group will undergo post-thyroidectomy ICG angiography only. The primary outcome measure will be the rate of patients with permanent hypoparathyroidism. Secondary outcome measures will be rate of postoperative hypoparathyroidism, the percentage of well vascularized parathyroid glands remaining in situ, the levels of iPTH and serum calcium after surgery and the influence of the type of vascular pattern of the parathyroid glands over these outcomes, as well as the safety profile of ICG angiography. Discussion: The results will contribute to adopt a new surgical strategy based on intraoperative ICG angiography before performing total thyroidectomy, according to which the rate of permanent hypoparathyroidism could be substantially reduced. Clinical trial registration: ClinicalTrials.gov. identifier NCT05573828.

Evaluation of Epithelial-Mesenchymal Transition Markers in Autoimmune Thyroid Diseases.

A state of chronic inflammation is common in organs affected by autoimmune disorders, such as autoimmune thyroid diseases (AITD). Epithelial cells, such as thyroid follicular cells (TFCs), can experience a total or partial transition to a mesenchymal phenotype under these conditions. One of the major cytokines involved in this phenomenon is transforming growth factor beta (TGF-ß), which, at the initial stages of autoimmune disorders, plays an immunosuppressive role. However, at chronic stages, TGF- ß contributes to fibrosis and/or transition to mesenchymal phenotypes. The importance of primary cilia (PC) has grown in recent decades as they have been shown to play a key role in cell signaling and maintaining cell structure and function as mechanoreceptors. Deficiencies of PC can trigger epithelial-mesenchymal transition (EMT) and exacerbate autoimmune diseases. A set of EMT markers (E-cadherin, vimentin, α-SMA, and fibronectin) were evaluated in thyroid tissues from AITD patients and controls through RT-qPCR, immunohistochemistry (IHC), and western blot (WB). We established an in vitro TGF-ß-stimulation assay in a human thyroid cell line to assess EMT and PC disruption. EMT markers were evaluated in this model using RT-qPCR and WB, and PC was evaluated with a time-course immunofluorescence assay. We found an increased expression of the mesenchymal markers α-SMA and fibronectin in TFCs in the thyroid glands of AITD patients. Furthermore, E-cadherin expression was maintained in these patients compared to the controls. The TGF-ß-stimulation assay showed an increase in EMT markers, including vimentin, α-SMA, and fibronectin in thyroid cells, as well as a disruption of PC. The TFCs from the AITD patients experienced a partial transition to a mesenchymal phenotype, preserving epithelial characteristics associated with a disruption in PC, which might contribute to AITD pathogenesis.

Transoral endoscopic thyroidectomy vestibular approach: Results after 53 first cases.

INTRODUCTION: Trans Oral Endoscopic Thyroidectomy through Vestibular Approach (TOETVA) allows access to the thyroid with the best cosmetic results as there are no visible scars. METHODS: Here we present a prospective observational study of 53 patients which underwent TOETVA from July 2017 to June 2021. RESULTS: Fifty-two cases (98.1%) cases were women (median age 44 years old). Thyroid nodule was the main surgical indication accounting 73.6% of cases. We performed 42 lobectomies and 11 total thyroidectomies; 4 left Central Neck Dissection (CND) were also associated. The median surgical time for port placement was 14 min and for lobectomy, total thyroidectomy and left CND were 80, 140 and 30 min, respectively. The median of hospital stay was 2 days. Dysphonia was present in 4 patients; however, laryngoscopy only confirmed laryngeal nerve impairment in 2 cases, one of them classified as permanent (1.6%). In those patients that underwent total thyroidectomy, the rate of transient hypoparathyroidism was 18.2% whereas permanent was 0%. Regarding complications associated to the new approach, transient chin numbness appeared in all patients with a variable degree of intensity. CONCLUSTIONS: Transoral surgery is a recent approach in our Unit. Our results, based on the first 53 patients, show that it is a safe and effective approach when performed in appropriately selected patients offering the best cosmetic result. Besides, new complications associated to the approach has been shown to be transient.

Usefulness of ICG Angiography-Guided Thyroidectomy for Preserving Parathyroid Function.

INTRODUCTION: Hypoparathyroidism is the most frequent complication after total thyroidectomy and, when permanent, it becomes a severe chronic disease. We assessed the usefulness of indocyanine green (ICG) angiography-guided thyroidectomy to reduce the postoperative hypocalcemia. METHODS: Prospective study with two consecutive cohorts of patients who underwent total thyroidectomy: historical control group (CG) and angiography-guided thyroidectomy group (AG). In all patients, ICG-angiography was performed at the end of the surgery to predict immediate parathyroid gland (PG) function. In the AG, ICG-angiography was also done after PG identification to show their vascular supply. We compared the rate of postoperative hypocalcemia (calcium supplementation needed due to hypocalcemia symptoms or calcium levels < 1.8 mmol/L on the first postoperative day) and permanent hypocalcemia (need of calcium ± vitamin D supplementation 12 months after thyroidectomy). RESULTS: We included 120 consecutive patients (84 CG; 36 AG). Thyroid cancer was the most common diagnostic (63.1% CG-69.4% AG; p = 0.646) and central neck dissection was also frequent (54.8% CG-64.3% AG; p = 0.468). The AG developed a lower rate of postoperative (26.2-5.6%; p = 0.011) and permanent hypocalcemia (11.9-0%; p = 0.032). The OR for permanent hypocalcemia was 0.673 (95% CI 0.591-0.766). A significant higher rate of well vascularized PG at the end of the surgery (score 2) in the AG (39.2-52.9%; p = 0.018) was also seen. CONCLUSION: ICG angiography-guided thyroidectomy is a useful tool to identify PG vascularization, allowing a better PG preservation and a significant decrease in hypocalcemia rates.

Impact of Change in Body Composition during Follow-Up on the Survival of GEP-NET.

Background: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are heterogeneous rare diseases causing malnutrition and cachexia in which the study of body composition may have an impact in prognosis. Aim: Evaluation of muscle and fat tissues by computed tomography (CT) at the level of the third lumbar (L3 level) at diagnosis and at the end of follow-up in GET-NET patients and their relationships with clinical and biochemical variables as predictors of survival. Methodology: Ninety-eight GEP-NET patients were included. Clinical and biochemical parameters were evaluated. Total body, subcutaneous, visceral and total fat areas and very low-density, low-density, normal density, high-density, very high-density and total muscle areas were obtained from CT images. Results: Body composition measures and overall mortality correlated with age, ECOG (Eastern Cooperative Oncology Group performance status) metastases, lactate dehydrogenase (LDH), albumin and urea levels. Although there was no relationship between body composition variables at diagnosis and overall and specific mortality, an increase in low-density muscle and a decrease in normal-density muscle during follow-up were independently correlated to overall (p <0.05) and tumor-cause mortality (p < 0.05). Conclusion: Although body composition measures obtained by CT at diagnosis did not impact survival of GEP-NET patients, a loss of good quality muscle during follow-up was associated with an increased overall and tumor-related mortality. Nutritional status should therefore be supervised by nutrition specialists and an increase in good quality muscle could improve prognosis.

Management of incidentally discovered appendiceal neuroendocrine tumors after an appendicectomy.

Appendiceal neuroendocrine tumors (aNETs) are an uncommon neoplasm that is relatively indolent in most cases. They are typically diagnosed in younger patients than other neuroendocrine tumors and are often an incidental finding after an appendectomy. Although there are numerous clinical practice guidelines on management of aNETs, there is continues to be a dearth of evidence on optimal treatment. Management of these tumors is stratified according to risk of locoregional and distant metastasis. However, there is a lack of consensus regarding tumors that measure 1-2 cm. In these cases, some histopathological features such as size, tumor grade, presence of lymphovascular invasion, or mesoappendix infiltration must also be considered. Computed tomography or magnetic resonance imaging scans are recommended for evaluating the presence of additional disease, except in the case of tumors smaller than 1 cm without additional risk factors. Somatostatin receptor scintigraphy or positron emission tomography with computed tomography should be considered in cases with suspected residual or distant disease. The main point of controversy is the indication for performing a completion right hemicolectomy after an initial appendectomy, based on the risk of lymph node metastases. The main factor considered is tumor size and 2 cm is the most common threshold for indicating a colectomy. Other factors such as mesoappendix infiltration, lymphovascular invasion, or tumor grade may also be considered. On the other hand, potential complications, and decreased quality of life after a hemicolectomy as well as the lack of evidence on benefits in terms of survival must be taken into consideration. In this review, we present data regarding the current indications, outcomes, and benefits of a colectomy.

A practical approach to normocalcemic primary hyperparathyroidism.

Normocalcemic primary hyperparathyroidism is an entity on which several issues about its clinical management remains unclear. This is reflected in the main current guidelines, where there are no evidence-based specific recommendations. Through an exhaustive review of current literature, a clinical management algorithm for these patients is proposed. We consider the diagnosis criteria, the differential diagnosis, the clinical manifestations, and the treatment indications. When indicated, we also review the preoperative locations techniques and the surgical approach. Finally, when surgical treatment is not indicated, the patient is not a candidate to surgery or refuse surgical management, we review the medical treatment options and the follow-up schemes.

Efficacy and safety of preoperative preparation with Lugol's iodine solution in euthyroid patients with Graves' disease (LIGRADIS Trial): Study protocol for a multicenter randomized trial.

BACKGROUND: Currently, both the American Thyroid Association and the European Thyroid Association recommend preoperative preparation with Lugol's Solution (LS) for patients undergoing thyroidectomy for Graves' Disease (GD), but their recommendations are based on low-quality evidence. The LIGRADIS trial aims to provide evidence either to support or refute the systematic use of LS in euthyroid patients undergoing thyroidectomy for GD. METHODS: A multicenter randomized controlled trial will be performed. Patients ≥18 years of age, diagnosed with GD, treated with antithyroid drugs, euthyroid and proposed for total thyroidectomy will be eligible for inclusion. Exclusion criteria will be prior thyroid or parathyroid surgery, hyperparathyroidism that requires associated parathyroidectomy, thyroid cancer that requires adding a lymph node dissection, iodine allergy, consumption of lithium or amiodarone, medically unfit patients (ASA-IV), breastfeeding women, preoperative vocal cord palsy and planned endoscopic, video-assisted or remote access surgery.Between January 2020 and January 2022, 270 patients will be randomized for either receiving or not preoperative preparation with LS. Researchers will be blinded to treatment assignment. The primary outcome will be the rate of postoperative complications: hypoparathyroidism, recurrent laryngeal nerve injury, hematoma, surgical site infection or death. Secondary outcomes will be intraoperative events (Thyroidectomy Difficulty Scale score, blood loss, recurrent laryngeal nerve neuromonitoring signal loss), operative time, postoperative length of stay, hospital readmissions, permanent complications and adverse events associated to LS. CONCLUSIONS: There is no conclusive evidence supporting the benefits of preoperative treatment with LS in this setting. This trial aims to provide new insights into future Clinical Practice Guidelines recommendations. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03980132.

Oxyphil cells in primary hyperparathyroidism: a clinicopathological study.

BACKGROUND: The role of oxyphil cells (OxC) in primary hyperparathyroidism (PHPT) still remains controversial. Historically, they were believed to be involuted cells. However, they could play an important role in hormone secretion. The clinical behavior of OxC-rich adenomas and preoperative PHPT localization tests have been widely studied. The aim of this study is to analyze the implications of OxC in PHTP. METHODS: A retrospective cohort study of patients undergoing parathyroidectomy for PHPT was conducted. Additionally, we included normal glands removed in the context of PHPT or inadvertently during a thyroidectomy. All glands were reviewed independently by three researchers, performing a semi-quantitative analysis of the percentage of OxC. Groups with < 25% OxC and > 75% OxC were compared. RESULTS: In the period 2010-2017, 238 patients and 261 removed glands were included (8.8% OxCA > 75%). There were no differences in symptomatology and levels of preoperative calcium, parathormone, or 25-OH vitamin. Patients with OxCA > 75% had worse preoperative glomerular filtration rate (81.2 vs. 69.7 mL/min/1.73 m2; p = 0.043). They also had a trend towards larger size and weight (17 vs. 20 mm, p = 0.135 and 562 vs. 875 mg, p = 0.495), while ultrasound was found to have better accuracy (48.3% vs. 73.7%; p = 0.035). There were no normal glands with a content of OxC > 75%. CONCLUSIONS: Our study suggests that phosphocalcic metabolism is not influenced by the presence of a high content of OxC in the parathyroid glands. A high content of OxC seems to be exclusive to pathologic glands and could be related to the deterioration of renal function in patients with PHPT.

Effect of preoperative potassium iodide administration on Graves' disease surgery: a propensity score analysis.

BACKGROUND: Preoperative administration of a saturated solution of potassium iodide (SSKI) is recommended in the guidelines for the management of hyperthyroidism due to Graves' disease. Studies addressing its effect on complications after thyroidectomy are inconclusive. METHODS: Retrospective multicenter Propensity Score study of patients undergoing total thyroidectomy for Graves' disease, from January 2013 to September 2019 in two tertiary centers in Madrid, Spain. Patients were given SSKI prior to surgery or not according to surgeons' preferences. Electronic clinical records were reviewed searching: baseline characteristics surgical variables, pathological findings, and postoperative complications. RESULTS: Ninety patients were analyzed: 44 received SSKI and 46 were not given SSKI. No significant differences were found in the main postoperative complications with or without SSKI: transient hypoparathyroidism (40.9% vs. 50%), permanent hypoparathyroidism (6.8% vs. 13%), transient recurrent laryngeal nerve (RLN) palsy (2.3% vs. 8.7%), definitive RLN palsy (2.3% vs. 2.2%), or cervical hematoma (2.3% vs. 4.3%). CONCLUSION: Preoperative administration of SSKI had no impact on postoperative complications after thyroidectomy for Graves' disease.

LAT-1 and GLUT-1 Carrier Expression and Its Prognostic Value in Gastroenteropancreatic Neuroendocrine Tumors.

Cancer cells develop mechanisms that increase nutrient uptake, including key nutrient carriers, such as amino acid transporter 1 (LAT-1) and glucose transporter 1 (GLUT-1), regulated by the oxygen-sensing Von Hippel Lindau-hypoxia-inducible factor (VHL-HIF) transcriptional pathway. We aimed to analyze these metabolic players in gastroenteropancreatic neuroendocrine tumors (GEP-NET) and correlate them with tumor malignancy and progression. LAT-1, GLUT-1, and pVHL expression was analyzed in 116 GEP-NETs and 48 peritumoral tissue samples by immunohistochemistry. LAT-1 was stably silenced using specific shRNA in the human NET BON cell line. LAT-1 expression was significantly increased in tumor tissue compared to non-tumor tissue in both gastrointestinal (67% vs. 44%) and pancreatic NETs (54% vs. 31%). Similarly, GLUT-1 was substantially elevated in gastrointestinal (74% vs. 19%) and pancreatic (58% vs. 4%) NETs. In contrast, pVHL expression was decreased (85% vs. 58%) in pancreatic NETs. Tumors with metastases at diagnosis displayed increased LAT-1 and GLUT-1 and decreased pVHL expression (p < 0.001). In accordance with these data, silencing LAT-1 curtailed cell proliferation in BON cells. These findings suggest that specific mechanisms that increase nutrient uptake, such as LAT-1 and GLUT-1, are increased in GEP-NETs, whereas pVHL is decreased. These markers might be related to the proliferation and metastatic capacity of these tumors.

[Elective surgery during the SARS-CoV-2 pandemic (COVID-19): a morbimortality analysis and recommendations on patient prioritisation and security measures]. / Cirugía electiva durante la pandemia por SARS-CoV-2 (COVID-19): análisis de morbimortalidad y recomendaciones sobre priorización de los pacientes y medidas de seguridad.

INTRODUCTION: The spread of the SARS-CoV-2 infection (COVID-19) has required adaptation by hospitals affected by the pandemic, which has caused a reduction in elective surgical activity. METHODS: Retrospective study of patients operated on in the previous month and during the peak of the pandemic. We analysed the COVID-19 infection rate, the severity of respiratory infection according to the Brescia respiratory COVID-19 severity scale, the adopted therapeutic measures and the overall postoperative complications. RESULTS: From 17th February to 31st March 2020, there was a progressive decrease in surgical activity, with only 213 patients operated on. This comprised 59 (27.8%) elective operations for oncological diseases, 97 (45.5%) elective operations for benign diseases and 57 (26.7%) as urgent procedures.There was a progressive increase in the rate of infection by COVID-19, with a total of 15 cases (7%). This included 10 patients (16.9%) in the elective group for oncological disease, 1 (1%) in the elective surgery group for benign disease and 4 (7%) in the urgent surgery group (p < 0.001). Five patients presented with a severe respiratory infection, of which 4 were affected by oncological disease. There were 3 deaths (1.4%), which were all due to the worsening of a respiratory infection. CONCLUSIONS: The patients undergoing the surgical procedures showed high rates of COVID-19 infection and postoperative complications, especially the patients with oncological diseases. Local resumption of surgical activity must be based on the prioritisation of the cases to be operated on, respecting certain premises of security and optimisation of the available resources.