AGK-BRAF is associated with distant metastasis and younger age in pediatric papillary thyroid carcinoma.

BACKGROUND: The incidence of thyroid carcinoma has increased in most populations, including pediatric patients. The increase is almost exclusively due to an increase in the incidence of papillary thyroid carcinoma (PTC). Genetic alterations leading to mitogen-activated protein kinase (MAPK) pathway activation are highly prevalent in PTC, with BRAF V600E mutation being the most common event in adult PTC. Although a lower prevalence of BRAF V600E had been reported among pediatric patients, a higher prevalence of BRAF fusion has been identified in both radiation-exposed and sporadic pediatric PTC. However, little is known about the prognostic implications of BRAF fusions in pediatric PTC. PROCEDURE: In this study, we investigated the prevalence of BRAF alterations (AGK-BRAF fusion and BRAF V600E mutation) in a large set of predominantly sporadic pediatric PTC cases and correlate with clinicopathological features. Somatic AGK-BRAF fusion was investigated by RT-PCR and confirmed by FISH break-apart. The BRAF V600E mutation was screened using Sanger sequencing. RESULTS: AGK-BRAF fusion, found in 19% of pediatric PTC patients, was associated with distant metastasis and younger age. Conversely, the BRAF V600E, found in 15% of pediatric PTC patients, was correlated with older age and larger tumor size. CONCLUSION: Collectively, our results advance knowledge concerning genetic bases of pediatric thyroid carcinoma, with potential implications for diagnosis, prognosis, and therapeutic approaches.

The diagnostic and prognostic role of miR-146b-5p in differentiated thyroid carcinomas.

Introduction: Samples classified as indeterminate correspond to 10-20% of cytologies obtained by fine needle biopsy of thyroid nodules, preventing an adequate distinction between benign and malignant lesions and leading to diagnostic thyroidectomies that often prove unnecessary, as most cases are benign. Furthermore, although the vast majority of patients with differentiated thyroid cancer (DTC) have such a good prognosis that active surveillance is permitted as an initial therapeutic option, relapses are not rare, and a non-negligible number of patients experience poor outcomes. MicroRNAs (miR) emerge as potential biomarkers capable of helping to define more precise management of patients in all these situations. Methods: Aiming to investigate the clinical utility of miR-146b-5p in the diagnostic of thyroid nodules and evaluating its prognostic potential in a realworld setting, we studied 89 thyroid nodule samples, correlating miR-146b-5p expression with clinical tools such as the 8th edition from the American Joint Committee on Cancer (AJCC/UICC) and the American Thyroid Association Guideline Stratification Systems for the rate of recurrence (RR). Results: miR-146b-5p expression levels distinguished benign from malignant thyroid FNA samples (p< 0.0001). For indeterminate nodules, overexpression of miR-146b-5p with a cut-off of 0.497 was able to diagnose malignancy with a 90% accuracy; specificity=87.5%; sensitivity=100%. An increased expression of miR-146b-5p was associated with greater RR (p=0.015). A cut-off of 2.21 identified cases with more vascular involvement (p=0.013) and a cut-off of 2.420 was associated with a more advanced TNM stage (p-value=0.047). Discussion: We demonstrated that miR-146b5p expression in FNA samples is able to differentiate benign from malignant indeterminate nodules and is associated with an increased risk of recurrence and mortality, suggesting that this single miRNA may be a useful diagnostic and prognostic marker in the personalized management of DTC patients.

NR3C1 rs6198 Variant May Be Involved in the Relationship of Graves' Disease with Stressful Events.

Although stressful events are known to trigger Graves' disease (GD), the mechanisms involved in this process are not well understood. The NR3C1 gene, encoding for the glucocorticoid receptor (GR), presents single nucleotide polymorphisms (SNPs) that are associated with stress-related diseases. To investigate the relationship between NR3C1 SNPs, GD susceptibility, and clinical features, we studied 792 individuals, including 384 patients, among which 209 presented with Graves' orbitopathy (GO), and 408 paired healthy controls. Stressful life events were evaluated in a subset of 59 patients and 66 controls using the IES-R self-report questionnaire. SNPs rs104893913, rs104893909, and rs104893911 appeared at low frequencies and presented similar profiles in patients and controls. However, variant forms of rs6198 were rarer in GD patients, suggesting a protective effect. Stressful events were more common in patients than controls, and were reported to have clearly occurred immediately before the onset of GD symptoms in 23 cases. However, no association was found between these events and rs6198 genotypes or GD/GO characteristics. We suggest that the NR3C1 rs6198 polymorphism may be an important protective factor against GD, but its relationship with stressful events needs further investigation.

Prognostic factors for incomplete response in thyroid microcarcinoma: an analysis of initial response to therapy in 517 patients.

OBJECTIVE: Although thyroid microcarcinoma (TMC) usually has a favorable prognosis, some patients present a higher risk of disease recurrence or persistence. Thus, we aimed at identifying possible risk factors associated with an incomplete response to therapy in TMC. METHODS: This was a retrospective study of 517 patients with TMC treated with total thyroidectomy, with or without radioactive iodine (RAI) therapy, reclassified after 1.1 ± 0.4 years according to the response to treatment into "favourable" (excellent/indeterminate) or "unfavorable" (biochemical/structural incomplete) responses. We evaluated participants' age, sex, tumor size, histological variants, multifocality, presence of vascular/lymphatic/perineural invasion, extrathyroidal extension, metastatic lymph nodes (LN), and distant metastasis. The effect of RAI therapy on the response range was analyzed in a given subgroup. RESULTS: The mean age observed was 46.4 ± 12.0 years, and 89.7% were female. We noted 97.5% with papillary carcinoma, 27.8% with multifocality and 11.2% with LN metastasis. Although the majority of patients had a low risk of recurrence/persistence (78%), 75% were submitted to RAI therapy. Incomplete response (20.7%) was associated with multifocality (p=0.041; OR=1.619) and metastatic LN (p=0.041; OR=1.868). These variables were strongly correlated (p=0.000; OR=3.283). No cut-off of tumor size was identified as a predictor of incomplete response by the receiver operating curve analysis. RAI treatment did not influence the response of patients with multifocality or LN metastasis. CONCLUSION: Multifocality and LN metastasis are independent risk factors for incomplete response in TMC patients and are strongly correlated. Additional RAI therapy was not associated with a more favorable response in these subgroups.

Intermediate-risk thyroid carcinoma: indicators of a poor prognosis.

OBJECTIVE: The intermediate-risk (IR) category includes tumors with different degrees of aggression. We aimed to identify the risk factors associated with unfavorable response to initial treatment and compare the effect of low/high radioactive iodine (RAI) therapy. METHODS: A total of 614 IR patients were selected from a database, during 1972-2015. All patients underwent total thyroidectomy and RAI therapy and were reclassified after 12-18 months into the favorable (complete/indeterminate) response group and the unfavorable (biochemical/incomplete structural) response group. A total of 92 patients were assessed for late response (mean: 9.19 ± 5.73 years). Age, gender, tumor size, histology, multifocality, vascular invasion, extrathyroidal extension, presence and number of lymph node metastasis, and stimulated thyroglobulin at ablation (sTg) were evaluated. RESULTS: Mean age at diagnosis was 41.47 ± 15.81 years, and 83.6% of the patients were female. Within 12-18 months after initial therapy, unfavorable response was detected in 41.2% of the patients and was associated, in multivariate analysis, with lymph node metastasis (p = 0.041; odds ratio [OR] = 1.9), presence of more than five metastatic lymph nodes (p = 0,017; OR = 2.6), and sTg > 10 ng/mL (p = 0.005; OR = 10.0). For patients with a longer follow-up, sTg >10 ng/mL was associated with unfavorable response (p = 0.002; OR = 6.8). A higher RAI dose was not related to better prognosis at the end of the follow-up. CONCLUSION: A sTg level of >10 ng/mL and lymph node metastasis were associated with an unfavorable response 12-18 months after initial treatment. A RAI dose below 150 mCi was proven sufficient to treat IR patients.

A Multifocal Pediatric Papillary Thyroid Carcinoma (PTC) Harboring the AGK-BRAF and RET/PTC3 Fusion in a Mutually Exclusive Pattern Reveals Distinct Levels of Genomic Instability and Nuclear Organization.

The spectrum and incidence of gene fusions in papillary thyroid carcinoma (PTC) can differ significantly depending on the age of onset, histological subtype or radiation exposure history. In sporadic pediatric PTC, RET/PTC1-3 and AGK-BRAF fusions are common genetic alterations. The role of RET/PTC as a prognostic marker in pediatric PTC is still under investigation. We recently showed that AGK-BRAF fusion is prevalent in young patients (mean 10 years) and associated with specific and aggressive pathological features such as multifocality and lung metastasis. In this pilot study, we report a unique patient harboring three different foci: the first was positive for AGK-BRAF fusion, the second was positive for just RET/PTC3 fusion and the third was negative for both rearrangements. To investigate whether AGK-BRAF and RET/PTC3 are associated with genomic instability and chromatin modifications, we performed quantitative fluorescence in situ hybridization (Q-FISH) of telomere repeats followed by 3D imaging analysis and 3D super-resolution Structured Illumination Microscopy (3D-SIM) to analyze the DNA structure from the foci. We demonstrated in this preliminary study that AGK-BRAF is likely associated with higher levels of telomere-related genomic instability and chromatin remodeling in comparison with RET/PTC3 foci. Our results suggest a progressive disruption in chromatin structure in AGK-BRAF-positive cells, which might explain a more aggressive disease outcome in patients harboring this rearrangement.

The impact of minimal extrathyroidal extension in the recurrence of papillary thyroid cancer patients.

OBJECTIVE: We aimed to evaluate the impact of minimal extrathyroidal extension (mETE) alone on the risk of recurrence of papillary thyroid carcinoma (PTC). The impact of other factors, including multifocality, age, tumor size, and stimulated thyroglobulin (sTg) values was also assessed. SUBJECTS AND METHODS: We retrospectively analyzed 1,108 PTC patients from a medical institution, who presented tumors ≤ 4 cm without any adverse characteristics other than mETE. Patients were classified according to their response to initial treatment 12 to 24 months after surgery as proposed by the 2015 American Thyroid Association (ATA) guideline. Statistical analysis was performed using multivariate logistic regression and receiver operating characteristic (ROC) curve. RESULTS: In the multivariate logistic regression analysis, mETE did not have an impact on the response to initial treatment (p = 0.44), similar to multifocality, age, and tumor size. Initial Tg value was the only variable associated with a poor response (p < 0.01, odds ratio = 1.303, 95% confidence interval 1.25-1.36). The ROC analysis revealed that Tg was significant (area under curve = 0.8750); the cutoff value of sTg as a predictor of poor response was 10 ng/mL (sensitivity = 72.2%, specificity = 98.5%). CONCLUSION: For low-risk PTC presenting mETE as the only aggressive feature, the initial sTg value is essential to identify patients who may have a poor response after initial treatment and benefit from further treatment. Arch Endocrinol Metab. 2020;64(3):251-6.

Elastography for the evaluation of thyroid nodules in pediatric patients.

OBJECTIVE: To evaluate the usefulness of elastography (using manual compression) as an additional diagnostic tool for children and adolescents with thyroid nodules. MATERIALS AND METHODS: This was a prospective study conducted between September 2012 and August 2013 at a hospital in Brazil. We performed elastography, ultrasound, and fine-needle aspiration biopsy in 32 patients between 6 and 18 years of age who had, in total, 38 thyroid nodules. RESULTS: The elastography findings correlated with the histopathological diagnosis in 78.5% of cases. In three patients, an unnecessary thyroidectomy could have been avoided if the elastography results had been prioritized. Only one malignant thyroid nodule was found to show high elasticity. CONCLUSION: Our results suggest that high elasticity of a nodule on elastography is associated with a low risk of thyroid cancer. If further confirmed in other studies, elastography may prove useful as a complementary test for screening thyroid nodules in children.

OBJETIVO: Avaliar a utilidade da elastografia (usando compressão manual) como uma ferramenta adicional de diagnóstico em crianças e adolescentes com nódulos da tireoide. MATERIAIS E MÉTODOS: Este foi um estudo prospectivo realizado entre setembro de 2012 e agosto de 2013 em um hospital no Brasil. Realizamos elastografia, ultrassonografia e biópsia por aspiração com agulha fina em 32 pacientes com idade entre 6 e 18 anos que tinham, no total, 38 nódulos tireoidianos. RESULTADOS: Os achados da elastografia em relação ao histopatológico foram corretos em 78,5% dos casos. A elastografia poderia ter evitado a tireoidectomia desnecessária de três pacientes. Apenas um nódulo maligno da tireoide foi classificado como E1. CONCLUSÃO: Nossos resultados sugeriram que a alta elasticidade de um nódulo na elastografia está associada a um baixo risco de câncer de tireoide. Caso se confirme em outros estudos, a elastografia pode ser útil como teste de triagem complementar de nódulos tireoidianos em crianças.

Genetic polymorphisms associated with cigarette smoking and the risk of Graves' disease.

OBJECTIVE: Cigarette smoking is a well-recognized risk factor of Graves' disease and, particularly, Graves' ophthalmopathy. Hence, germline polymorphisms of detoxification genes and genes belonging to the major DNA repair-apoptosis pathways might have an important role in disease susceptibility. In addition, as some of these genes are regulated by thyroid hormones, they may affect the patients' outcomes. We aimed to assess the influence of the GST, CYP and TP53 gene polymorphisms in the risk of Graves' disease and its outcome. DESIGN: Prospective case-control study. PATIENTS: A PCR-based strategy was used for GSTT1, GSTM1, GSTP1, CYP1A1 and TP53 codon 72 genotypes in a group of 400 Graves' disease patients, and to compare them to 574 control individuals with similar environmental exposure features. RESULTS: GSTM1 and GSTT1 genotypes were equally distributed in cases and controls, respectively. However, GSTP1 (P < 0.0001), CYP1A1 (P < 0.0033) and Pro/ProTP53 (P < 0.0035) variants appeared more frequently in Graves' disease patients than in controls. A multivariate analysis indicated that cigarette smoking and inheritance of GSTP1, CYP1A1 and Pro/ProTP53 variants were important risk factors for Graves' disease, but only smoking appeared as an independent risk factor for Graves' ophthalmopathy. There was no association between clinical features, including ophthalmopathy or treatment outcome, and the studied genotypes. CONCLUSION: We concluded that GSTP1, CYP1A1 and TP53, but not GSTT1 and GSTM1 germline polymorphisms, may be associated with smoking-related Graves' disease susceptibility and configure a risk profile for the disease. However, these polymorphisms do not influence the patients' response to treatment.

Graves' disease in Brazilian children and adults: lack of genetic association with CTLA-4 +49A>G polymorphism.

BACKGROUND/AIM: In several populations, major histocompatibility complex and CTLA-4 (cytotoxic T lymphocyte antigen-4) gene polymorphisms are related to adult subjects with Graves' disease (GD). Our aim was to study the association of +49A>G polymorphism of the CTLA-4 gene in Brazilian children and adults with GD and its correlation with clinical and laboratory markers of disease severity. METHODS: CTLA-4 +49A>G polymorphism was established by polymerase chain reaction-restriction fragment length polymorphism analysis in 44 children and 72 adults with GD and compared to a stringent control group consisting of octogenarians with no history of thyroid disease; free T4 and T3 levels and T3/T4 ratio, antithyroid antibodies, and Graves' ophthalmopathy were also evaluated according to genotype. RESULTS: No significant difference was found in the frequency of CTLA-4 +49A>G polymorphism among children and adults with GD compared to controls and within groups. There was no significant correlation between the presence of G allele and Graves' ophthalmopathy, gender, age at diagnosis, and biochemical markers of disease severity. CONCLUSION: The frequency of CTLA-4 +49A>G polymorphism is not different in children and adults with GD compared to the normal control population and does not seem to contribute independently to the severity of the clinical presentation of GD.

Acute effects of radioiodine therapy on the voice and larynx of Basedow-Graves patients.

UNLABELLED: Graves's disease is the most common cause of hyperthyroidism. There are three current therapeutic options: anti-thyroid medication, surgery, and radioactive iodine (I 131). There are few data in the literature regarding the effects of radioiodine therapy on the larynx and voice. The aim and the AIM: os this study was: to assess the effect of radioiodine therapy on the voice of Basedow-Graves patients. MATERIAL AND METHOD: A prospective study was done. Following the diagnosis of Grave's disease, patients underwent investigation of their voice, measurement of maximum phonatory time (/a/) and the s/z ratio, fundamental frequency analysis (Praat software), laringoscopy and (perceptive-auditory) analysis in three different conditions: pre-treatment, 4 days, and 20 days post-radioiodine therapy. Conditions are based on the inflammatory pattern of thyroid tissue (Jones et al. 1999). RESULTS: No statistically significant differences were found in voice characteristics in these three conditions. CONCLUSION: Radioiodine therapy does not affect voice quality.

Experiência de reforma curricular com participação da comunidade acadêmica e ensino baseado em competências / Curricular Reform Experience with Academic Community Participation and Competency-Based Education

Resumo: Introdução: Repensar os processos de ensino-aprendizagem é tarefa contínua dentro da escola médica, devendo haver aplicação das melhores evidências. Embora as necessidades de mudanças sejam amplamente conhecidas, os meios para realizá-las não o são. Por isso, este relato objetiva descrever a metodologia utilizada por uma faculdade tradicional do ensino em medicina durante seu processo de reforma curricular, o qual contou com a participação ativa da comunidade acadêmica. Relato de experiência: Para a reforma da matriz, foi nomeada uma comissão composta por alunos, docentes e funcionários. Seguindo os princípios do Design Thinking, organizaram-se os conhecimentos prévios e estruturaram-se os processos de escuta dos diferentes sujeitos. Optou-se por desenvolver uma matriz baseada em competências, com disciplinas integradas horizontalmente e priorização de atividades práticas, de modo a permitir uma redução da carga horária global do curso. As reformas implementadas exigiram alterações institucionais complexas para além da matriz, como a mudança da cultura avaliativa, a implementação do portfólio e outras questões de currículo oculto. Discussão: Superou-se o desafio de criar processos flexíveis e sustentáveis porque a comunidade foi capacitada para colaborar na gestão do ensino. Para além de coordenadores e diretores, todos os agentes do processo de aprendizagem devem ser reunidos de forma horizontal com participação ativa na proposição de mudanças. Barreiras e distanciamentos em relação à literatura podem ser enfrentados, devendo-se admitir as limitações para preservar identidades próprias e garantir projetos viáveis. Conclusão: A formação de profissionais competentes é o objetivo dos currículos em medicina, que devem ser revistos continuamente. A reforma descrita permitiu o fortalecimento de vínculos com a comunidade, entregando um projeto representativo e adequado à realidade específica.

Abstract: Introduction: Rethinking the teaching-learning process is a continuous task in medical training, with the constant requirement of applying the best evidence. Although the needs for change are widely known, the means to carry them out are not. Therefore, this report aims to describe the methodology used by a traditional medical school during its curricular reform process, which had the active participation of the academic community. Experience: A committee for curricular reform was appointed, including students, academic and professional staff. Following the principles of Design Thinking, prior knowledge was organized and listening processes were structured. A competency-based matrix was developed, with horizontally integrated disciplines and prioritization of practical activities, allowing for reduced total class hours of the course. The implemented reforms required complex institutional changes beyond the matrix, such as changing the evaluative culture and the implementation of the portfolio, in addition to other hidden curricular issues. Discussion: The challenge of creating flexible and sustainable processes seems to be overcome by empowering the community to collaborate with the educational management. In addition to coordinators and directors, all agents of the learning process must be brought together horizontally with active participation in proposing changes. Barriers and distances in relation to literature can be faced, and limitations must be admitted in order to preserve appropriate identities and guarantee viable projects. Conclusion: Training competent professionals is the goal of curricula, which must be continually reviewed. The reform described allowed for the strengthening of ties between the community, delivering a representative project that was adequate to the specific reality.

Hyperglycemia effect on coronary disease in patients with metabolic syndrome evaluated by intracoronary ultrasonography.

INTRODUCTION: Metabolic syndrome (MS) is characterized by dyslipidemia, central obesity, hypertension and hyperglycemia. However, type 2 diabetes mellitus (T2DM) may or may not be present in metabolic syndrome. MS and T2DM are considered important cardiovascular risk factors, but the role of hyperglycemia in coronary disease is still contested in the literature. Therefore, we decided to evaluate the effect of hyperglycemia on the severity of coronary disease in MS patients, with or without T2DM, submitted to coronary angiography (CA) and intravascular ultrasonography (IVUS). MATERIALS AND METHODS: This is a cross sectional, observational study with 100 MS patients (50% with T2DM), 60% male. All of the patients had been referred for CA procedures. The obstruction was considered severe when stenosis was greater than 70% and moderate if it was between 50-69%. Patients detected with a moderate obstruction by CA were indicated to IVUS. A minimal luminal area of less than 4mm2 detected by IVUS was also considered severe. IDF criteria were used to define Metabolic Syndrome and T2DM diagnosis was defined according to the American Diabetes Association criteria. Student's t-test and Pearson Chi-square were used for statistical analysis, considering p < 0.05 statistically significant. RESULTS AND DISCUSSION: The majority of T2DM patients presented severe arterial lesions (74% vs 22%, p<0.001). Using CA procedure, 12% of T2DM had moderate obstructions, compared to 38% of the non-diabetic group (p< 0.05). 8% of patients with moderate lesions by CA were diagnosed with a luminal area less than 4mm2 using IVUS. This luminal area was significantly smaller in the T2DM group than in the control group (3.8mm2 ± 2.42. vs 4.6mm2 ± 2.58, p = 0.03). CONCLUSION: Patients with MS and T2DM submitted to angiography and IVUS, had more severe coronary lesions compared to MS patients without diabetes. This finding suggests that beyond insulin resistance that is present in MS, hyperglycemia may also play a role in the development of atherosclerotic disease. IVUS was useful for diagnosing 8% of severe cases initially considered to be moderate obstructions when using just CA in this scenario.

Distinct inflammatory gene expression in extraocular muscle and fat from patients with Graves' orbitopathy.

OBJECTIVE: This study sought to compare patients with thyroid eye disease (TED) and normal controls with respect to the expression of the NR3C1, CHUK, IKBKB, FOS, NFKB and HSD11B1 genes in orbital fat (OF) and extraocular muscle (EOM). DESIGN AND METHODS: A prospective study design was used to evaluate 34 TED patients and 38 healthy controls. OF was harvested from 33 TED patients and 27 controls. EOM biopsies were obtained from 32 TED patients and 18 controls. Samples were examined by real-time PCR and evaluated using appropriate statistical analyses with a significance cut-off of P < 0.05. RESULTS: NR3C1 mRNA levels were higher in TED EOM (median 213 (96-376)) than those in control EOM (78 (34-138)) (P < 0.001), and NFKB expression was elevated in TED muscle (223 (31-520)) relative to that in control muscle (8 (6-31)) (P < 0.001). HSD11B1 expression was higher in TED EOM (0.78 (0.47-2.01)) than that in control EOM (0.22 (0.09-0.51)) (P < 0.001). Levels of CHUK, IKBKB, and FOS were higher in TED EOM (115 (20-223), 111 (54-299) and 0.11 (0.03-0.19), respectively) than those in control EOM (5.8 (2-13), 21 (5-52) and 0.05 (0.001-0.03) respectively) (P < 0.001). CONCLUSION: Tissues involved in GO exhibited different mRNA levels of NR3C1, CHUK, IKBKB, FOS, NFKB and HSD11B1. Gene expression in OF was similar for TED patients and controls. CHUK, IKBKB, FOS, NFKB, and HSD11B1 mRNA levels were higher in TED EOM than those in control EOM. NFKB was disproportionally elevated compared with NR3C1; this finding was indicative of a local proinflammatory profile.

Thyroglobulin levels before radioactive iodine therapy and dynamic risk stratification after 1 year in patients with differentiated thyroid cancer.

OBJECTIVES: We sought to assess the relationship between stimulated thyroglobulin (sTg) before radioactive iodine therapy (RIT), and the dynamic risk stratification 1 year after treatment, and to establish the utility of the sTg as a predictor of response to therapy in these patients. A retrospective chart review of patients with differentiated thyroid cancer (DTC) who underwent RIT after surgery and were followed for at least 1 year, was carried out. SUBJECTS AND METHODS: Patients were classified according to the dynamic risk stratification 1 year after initial treatment. The sTg values before RIT were compared among the groups. ROC curve analysis was performed. RESULTS: Fifty-six patients were enrolled (mean age 44.7 ± 14.4 years, 80.7% had papillary carcinoma). Patients with excellent response had sTg = 2.1 ± 3.3 ng/mL, those with indeterminate response had sTg = 8.2 ± 9.2 ng/mL and those with incomplete response had sTg = 22.4 ± 28.3 ng/mL before RIT (p = 0.01). There was a difference in sTg between excellent and incomplete response groups (p = 0.009) while no difference was found between indeterminate and either excellent or incomplete groups. The ROC curve showed an area under the curve of 0.779 assuming a sTg value of 3.75 ng/mL. CONCLUSION: Our study results suggest that the higher the sTg before RIT, the greater the likelihood of an incomplete response to initial treatment. A sTg cut-off of 3.75 ng/mL was found to be a good predictor of response to initial treatment in patients with DTC.

Fusion Oncogenes Are the Main Genetic Events Found in Sporadic Papillary Thyroid Carcinomas from Children.

BACKGROUND: Previous studies reported significant differences in the clinical presentation and outcomes of papillary thyroid carcinoma (PTC) in pediatric patients compared with adults. Previous studies have suggested that the clinicopathological differences observed between pediatric and adult PTCs may be due the existence of distinct genetic alterations. However, the knowledge of genetic events in pediatric PTCs is based primarily on studies in radiation-exposed PTCs or in the few studies that enrolled predominantly adolescent patients. The aim of this study was to characterize the known oncogenic alterations of the MAPK pathway found in adult and radiation-exposed PTCs in a cohort of predominantly sporadic pediatric PTC patients. METHODS: Thirty-five pediatric PTCs were screened for the most prevalent fusions (RET/PTC1, RET/PTC2, RET/PTC3, ETV6-NTRK3, and AGK-BRAF) and point mutations (BRAFV600E and NRASQ61) described in sporadic pediatric PTCs. The mutational status was correlated with clinicopathological data. RESULTS: Mutations were found in 20 out of 35 (57%) PTC cases. Fusion oncogenes were the main genetic alterations found. RET/PTC1-3 rearrangements were found in 13 (37%), ETV6-NTRK3 in 3 (9%), AGK-BRAF in 4 (11%), and BRAFV600E in 3 (9%). No mutation was found in NRASQ61. BRAFV600E was associated with older age and larger tumor size (p < 0.05), and RET/PTC3 was associated with a larger tumor size and multifocality (p < 0.05). CONCLUSIONS: The genetic signature in this cohort was remarkably different than that observed in adults. Although observed at a lower prevalence, the spectrum of mutations was quite similar to that described in radiation-exposed pediatric PTCs. As mutations were unidentifiable in over 40% of the PTC cases, more comprehensive studies conducted in these patients will help to decipher the genetic landscape of sporadic pediatric PTCs.

Human Lymph Node-Derived Fibroblastic and Double-Negative Reticular Cells Alter Their Chemokines and Cytokines Expression Profile Following Inflammatory Stimuli.

Lymph node (LN) is a secondary lymphoid organ with highly organized and compartmentalized structure. LNs harbor B, T, and other cells among fibroblastic reticular cells (FRCs). FRCs are characterized by both podoplanin (PDPN/gp38) expression and by the lack of CD31 expression. FRCs are involved in several immune response processes but mechanisms underlying their function are still under investigation. Double-negative cells (DNCs), another cell population within LNs, are even less understood. They do not express PDPN or CD31, their localization within the LN is unknown, and their phenotype and function remain to be elucidated. This study evaluates the gene expression and cytokines and chemokines profile of human LN-derived FRCs and DNCs during homeostasis and following inflammatory stimuli. Cytokines and chemokines secreted by human FRCs and DNCs partially diverged from those identified in murine models that used similar stimulation. Cytokine and chemokine secretion and their receptors expression levels differed between stimulated DNCs and FRCs, with FRCs expressing a broader range of chemokines. Additionally, dendritic cells demonstrated increased migration toward FRCs, possibly due to chemokine-induced chemotaxis since migration was significantly decreased upon neutralization of secreted CCL2 and CCL20. Our study contributes to the understanding of the biology and functions of FRCs and DNCs and, accordingly, of the mechanisms involving them in immune cells activation and migration.

Thyroid-Specific Genes Expression Uncovered Age-Related Differences in Pediatric Thyroid Carcinomas.

Despite a more advanced stage of disease at presentation, a better response to radioiodine (RAI) therapy and a reduced overall mortality have been reported in pediatric differentiated thyroid cancer (DTC) in comparison to adult DTC. Few studies suggested that the better response to RAI therapy in pediatric patients might be associated with an increased expression of NIS. However, a marked heterogeneity within the pediatric group has been recognized. Children (<10 years old) usually present a more aggressive disease than adolescents (≥10-18 years old). By analyzing the expression of thyroid-specific genes in 38 sporadic pediatric tumors, we show that the expression of NIS, PDS, and TSHR was lower in children than adolescents (P < 0.05). A linear regression confirmed the association between NIS expression and age. Most significantly, NIS was expressed at similar levels in DTC from children and adults, whereas PDS and TSHR expression was even lower in DTC from children, compared to adolescents and adults. Our data suggest that biological behaviors of DTC in adolescents might differ from those in children and adults. Therefore, the premise that the expression of thyroid-specific genes is higher in tumors from pediatric patients than in adults is not entirely true and might be too oversimplified.

AGK-BRAF gene fusion is a recurrent event in sporadic pediatric thyroid carcinoma.

Thyroid cancer is the fastest increasing cancer worldwide in all age groups. Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer in both adults and children. PTC genomic landscape has been extensively studied in adults, but information regarding sporadic pediatric patients is lacking. Although BRAF V600E mutation is highly prevalent in adults, this mutation is uncommon in pediatric cases. As adult and pediatric PTC is a mitogen-activated protein kinase-driven cancer, this altered pathway might be activated by different genetic events. The aim of this study was to investigate the occurrence of AGK-BRAF fusion gene, recently described in radiation-exposed pediatric PTC, in a cohort of exclusively sporadic pediatric PTC. The series consisted of 30 pediatric PTC younger than 18 years of age at the time of diagnosis and 15 matched lymph node metastases (LNM). Primary tumors and matched LNM were screened for the presence of the AGK-BRAF fusion transcript by RT-PCR. To confirm the identity of the amplified products, randomly selected samples positive for the presence of the fusion transcripts were sequenced. Moreover, BRAF dual-color, break-apart probes confirmed BRAF rearrangement. Overall, the AGK-BRAF fusion gene was detected in 10% (3/30) of primary tumors. For one of these cases, paired LNM was also available, which also shows the presence of AGK-BRAF fusion gene. This study described, for the first time, the presence of AGK-BRAF in sporadic pediatric PTC. Understanding the molecular events underlying pediatric PTC may improve preoperative diagnosis, allow molecular prognostication and define a therapeutic approach toward sporadic PTC patients.

Prognostic factors for incomplete response in thyroid microcarcinoma: an analysis of initial response to therapy in 517 patients

ABSTRACT Objective: Although thyroid microcarcinoma (TMC) usually has a favorable prognosis, some patients present a higher risk of disease recurrence or persistence. Thus, we aimed at identifying possible risk factors associated with an incomplete response to therapy in TMC. Subjects and methods: This was a retrospective study of 517 patients with TMC treated with total thyroidectomy, with or without radioactive iodine (RAI) therapy, reclassified after 1.1 ± 0.4 years according to the response to treatment into "favorable" (excellent/indeterminate) or "unfavorable" (biochemical/structural incomplete) responses. We evaluated participants' age, sex, tumor size, histological variants, multifocality, presence of vascular/lymphatic/perineural invasion, extrathyroidal extension, metastatic lymph nodes (LN), and distant metastasis. The effect of RAI therapy on the response range was analyzed in a given subgroup. Results: The mean age observed was 46.4 ± 12.0 years, and 89.7% were female. We noted 97.5% with papillary carcinoma, 27.8% with multifocality and 11.2% with LN metastasis. Although the majority of patients had a low risk of recurrence/persistence (78%), 75% were submitted to RAI therapy. Incomplete response (20.7%) was associated with multifocality (p=0.041; OR=1.619) and metastatic LN (p=0.041; OR=1.868). These variables were strongly correlated (p=0.000; OR=3.283). No cut-off of tumor size was identified as a predictor of incomplete response by the receiver operating curve analysis. RAI treatment did not influence the response of patients with multifocality or LN metastasis. Conclusion: Multifocality and LN metastasis are independent risk factors for incomplete response in TMC patients and are strongly correlated. Additional RAI therapy was not associated with a more favorable response in these subgroups.