Molecular Markers Involved in Tumorigenesis of Thyroid Carcinoma: Focus on Aggressive Histotypes.

Thyroid cancer derived from follicular cells (TCDFC) comprises well-differentiated (papillary and follicular) carcinoma, poorly differentiated carcinoma, and anaplastic carcinoma. Papillary thyroid carcinoma is the most common endocrine cancer, and its incidence is steadily increasing. Lethality and aggressiveness of TCDFC is inversely correlated with differentiation degree. In this review, an emphasis has been put on molecular markers involved in tumorigenesis of thyroid carcinoma with a focus on aggressive histotypes and the role of such biomarkers in predicting thyroid cancer outcome. Genetic rearrangements in TCDFC (RET/PTC, PAX8/PPARG) and mutations in RAS, BRAF, TERT promoter (TERTp), TP53, PIK3CA, and AKT1 are discussed. The majority of the studies to date indicate that TERTp mutations can serve as a marker of more aggressive disease in all the subtypes of thyroid carcinoma, being the best current marker of poor prognosis, due to its independent association with distant metastases and increased disease-specific mortality. Some studies suggested that a more accurate prediction of thyroid cancer outcome may be possible through a more extensive genetic analysis. The same is true concerning the identification of other mutations that are only relatively frequent in advanced tumors (e.g., TP53, PIK3CA, or AKT1). A better understanding of the prognostic role of TERTp mutation (together with additional ones like BRAF, RAS, PIK3CA, AKT1, or TP53) and the clarification of their putative role in fine-needle aspiration biopsies are likely to allow, in the future, an early refinement of the stratification risk in patients with well-differentiated carcinomas. It is worth noting that, as with any categorical staging system, the risk evaluation within each category (low, intermediate, and high) varies depending on the specific clinicopathologic features of individual patients and the specific biological behavior of the tumor. Finally, besides the diagnostic and/or prognostic significance of the above-mentioned mutations, it is crucial to understand that the molecular pathways and epigenetic alterations will likely turn into interesting targets for new therapies.

A Cross-Sectional Analysis of Cardiovascular and Bone Health Care Utilization During Treatment With Thyroid Hormone.

CONTEXT: Combination therapy with levothyroxine and liothyronine (LT4 + LT3) and desiccated thyroid extract (DTE) make up >10% of new thyroid hormone (TH) prescriptions in the United States. OBJECTIVE: To assess health care utilization related to cardiovascular disease (CVD) and bone health (BH) events (atrial fibrillation [AF], heart failure [HF], myocardial infarction [MI], stroke, and osteoporosis/fractures [FX]) in participants taking LT4+LT3 or DTE surveyed in the Medical Expenditure Panel Survey database. MATERIALS AND METHODS: Multi-year cross-sectional analysis examining 5437 participants (≥18 years old) treated with LT4, LT4+LT3, or DTE between 2016 and 2020. Health care utilization was assessed through outpatient, emergency, and hospital visits for AF, HF, MI, stroke, FX, and a composite index. A weighted analysis provided national estimates of health care utilization parameters. Utilization was re-analyzed following propensity score-based matching to balance sociodemographic and clinical covariates between treatment groups. Additionally, provider type and specialty data were obtained from visits associated with TH prescriptions. RESULTS: 5106 participants were treated with LT4 monotherapy, 252 with DTE, and 79 with LT4 + LT3. Prevalence of combined outpatient CVD and BH-related care utilization was lower among DTE/LT4+LT3 vs LT4 users (3.5% vs 7.7%; P = .008). There were no differences in emergency/hospital events. After covariate balancing, CVD and BH-related care utilization was similar between groups in outpatient and emergency/hospital settings. LT3 and DTE made up 7.6% of all TH prescriptions. For visits associated with DTE prescriptions, nurse practitioners and alternative medicine professionals were more likely to be identified as the primary provider type. CONCLUSION: No significant differences in CVD- and BH-related health care utilization were identified between LT4 and DTE/LT4+LT3 users after covariate balancing. Non-MD providers were more likely to prescribe DTE.

Thyroid hormone homeostasis in levothyroxine-treated patients: Findings from ELSA-Brasil.

CONTEXT: The effectiveness of levothyroxine (LT4) in restoring thyroid hormone (TH) homeostasis, particularly serum thyroxine (T4) and triiodothyronine (T3) levels, remains debatable. OBJECTIVE: To assess TH homeostasis in LT4-treated individuals using data from the Longitudinal Study of Adult Health in Brazil (ELSA-Brasil) study. METHODS: The ELSA-Brasil study follows 15,105 adult Brazilians (aged 35 to 74 years) over 8.2 years (2008-2019) with 3 observation points assessing health parameters including serum thyroid stimulating hormone (TSH), free T4 (FT4), and free T3 (FT3) levels. We analyzed 186 participants that initiated treatment with LT4 during the study, and 243 individuals continuously treated with LT4 therapy. RESULTS: Initiation of therapy with LT4 resulted in a 11-19% decrease in TSH, a ∼19% increase in FT4, and a 7% reduction in FT3 serum levels (FT3 dropped >10% in ∼40% of the LT4-treated patients). This was associated with an increase in triglyceride levels and utilization of hypolipidemic and anti-diabetic medications. Participants continuously treated with LT4 exhibited a stable elevation in serum FT4 and, a reduction in serum FT3 and TSH levels. While 115 participants (47.3%) had at least one serum FT4 levels above the control reference range (>1.52 ng/dL), 38 participants (15.6%) had at least one serum FT3 below the reference range (<0.23 ng/dL). CONCLUSION: The present results challenge the dogma that treatment with LT4 for hypothyroidism restores TH homeostasis in all patients. A substantial number of LT4-treated patients exhibit repeated FT4 and FT3 levels outside the normal reference range, despite normal TSH levels. Further studies are needed to define the clinical implications of these findings.

TSH Trajectories During Levothyroxine Treatment in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) Cohort.

CONTEXT: Thyroid-stimulating hormone (TSH) trajectory classification represents a novel approach to defining the adequacy of levothyroxine (LT4) treatment for hypothyroidism over time. OBJECTIVE: This is a proof of principle study that uses longitudinal clinical data, including thyroid hormone levels from a large prospective study to define classes of TSH trajectories and examine changes in cardiovascular (CV) health markers over the study period. METHODS: Growth mixture modeling (GMM), including latent class growth analysis (LCGA), was used to classify LT4-treated individuals participating in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) based on serial TSH levels. Repeated measure analyses were then utilized to assess within-class changes in blood pressure, lipid levels, hemoglobin A1c, and CV-related medication utilization. RESULTS: From the 621 LT4-treated study participants, the best-fit GMM approach identified 4 TSH trajectory classes, as defined by their relationship to the normal TSH range: (1) high-high normal TSH, (2) normal TSH, (3) normal to low TSH, and (4) low to normal TSH. Notably, the average baseline LT4 dose was lowest in the high-high normal TSH group (77.7 µg, P < .001). There were no significant differences in CV health markers between the classes at baseline. At least 1 significant difference in CV markers occurred in all classes, highlighted by the low to normal class, in which total and high-density lipoprotein cholesterol, triglycerides, and A1c all increased significantly (P = .049, P < .001, P < .001, and P = .001, respectively). Utilization of antihypertensive, antihyperlipidemic, and antidiabetes medications increased in all classes. CONCLUSION: GMM/LCGA represents a viable approach to define and examine LT4 treatment by TSH trajectory. More comprehensive datasets should allow for more complex trajectory modeling and analysis of clinical outcome differences between trajectory classes.

Gene polymorphisms and thyroid hormone signaling: implication for the treatment of hypothyroidism.

INTRODUCTION: Mutations and single nucleotide polymorphisms (SNPs) in the genes encoding the network of proteins involved in thyroid hormone signaling (TH) may have implications for the effectiveness of the treatment of hypothyroidism with LT4. It is conceivable that loss-of-function mutations or SNPs impair the ability of LT4 to be activated to T3, reach its targets, and ultimately resolve symptoms of hypothyroidism. Some of these patients do benefit from therapy containing LT4 and LT3. METHODS: Here, we reviewed the PubMed and examined gene mutations and SNPs in the TH cellular transporters, deiodinases, and TH receptors, along with their impact on TH signaling, and potential clinical implications. RESULTS: In some mechanisms, such as the Thr92Ala-DIO2 SNP, there is a compelling rationale for reduced T4 to T3 activation that limits the effectiveness of LT4 to restore euthyroidism. In other mechanisms, a potential case can be made but more studies with a larger number of individuals are needed. DISCUSSION/CONCLUSION: Understanding the clinical impact of the genetic makeup of LT4-treated patients may help in the preemptive identification of those individuals that would benefit from therapy containing LT3.

TERTp mutation is associated with a shorter progression free survival in patients with aggressive histology subtypes of follicular-cell derived thyroid carcinoma.

PURPOSE: Evaluate the impact of TERTp mutation on the outcomes after initial treatment of 45 patients with thyroid carcinomas derived from follicular cells (TCDFC) with aggressive histology, in which the role of this mutation is not yet well defined. METHODS: Analysis of the presence of TERTp (-124C > T and -146C > T), BRAF (V600E), and NRAS (Q 61R) mutations by Sanger sequencing and analysis of their correlation with the patient's outcomes. RESULTS: Forty-five patients with aggressive histopathologic variants were included in the study. Of these, 68.9% had aggressive variants of papillary thyroid cancer (PTC), 22.2% had poorly differentiated thyroid carcinoma (PDTC)/insular carcinoma, and 8.9% had invasive follicular thyroid cancer (FTC) with Hurthle cell features (Hurthle cell carcinoma). Lymph node metastases were present in 46.7% and distant metastases in 54.6%. The response to the initial therapy was excellent in 45.5% and structurally incomplete in 50%. During the follow-up period (median of 56 months; 5-360 months), 47.7% presented with disease progression and 17.8% experienced disease-related death. In 53.3% of the cases at least one molecular alteration (TERTp in 33.4%, BRAF in 24.5%, RAS in 8.9%) was detected. In the multivariate analysis, TERTp mutation was the factor associated with the highest risk (6 times) of having structural disease after initial therapy (p = 0.01), followed by vascular invasion (p = 0.02), gross extrathyroidal extension (ETE) (p = 0.02) and distant metastasis (p = 0.04). Regarding mutational status, only TERTp mutation was associated with disease progression, and diminished disease progression-free survival (PFS). The presence of distant metastasis, vascular invasion and gross ETE were significantly associated with the risk of disease progression. CONCLUSIONS: TERTp mutation appears be an indicator of both persistence and progression of structural disease after initial therapy in aggressive variants of TCDFC, and associates with a shorter progression free survival regardless of the therapy employed.

[Comparison between pre-thickened and home-thickened formulas in gastroesophageal reflux treatement]. / Comparação entre uma fórmula infantil pré-espessada e fórmula de espessamento caseiro no tratamento do refluxo gastroesofágico.

OBJECTIVE: The purpose of this study was to compare the effectiveness of a pre-thickened infant formula (Nan AR) with a conventional homemade formula in the reduction of regurgitation and vomiting in infants with gastroesophageal reflux.\par METHODS: A hundred children, under 12 months, not exclusively breast feeding, were select for the study. Forty-eight were treated with conventional formula with starch and 52 with pre-thickened infant formula.\par RESULTS: There was no statistically significant difference between the two groups in the improvement or cure of symptoms, each treatment having been effective.\par CONCLUSION: Thickened formulas, pre-thickened or home-thickened, have shown the same efficacy in the management of gastroesophageal reflux in children.

Comparação entre uma fórmula infantil pré-espessada e fórmula de espessamento caseiro no tratamentodo refluxo gastroesofágico / Comparison between pre-thickened and home-thickened formulas in gastroesophageal reflux treatment

Objetivo: o presente estudo foi realizado com o objetivo de comparar a eficácia de uma fórmula infantil pré-espessada (Nan AR) com fórmula convencional, de espessamento caseiro, com amido de milho, na redução de episódios de regurgitações e vômitos de lactentes com refluxo gastroesofágico (RGE). Métodos: foram estudadas 100 crianças, menores de 12 meses de idade, que não faziam uso de leite materno exclusivo. Por sorteio, 48 receberam fórmula convencional, e 52 receberam fórmula infantil pré-espessada (Nan AR), com comparação dos resultados clínicos após 3 meses. Resultados: não houve diferença estatisticamente significativa na melhora ou cura dos sintomas entre os dois grupos, tendo sido ambos os tratamentos eficazes. Conclusões: o espessamento dietético, seja com fórmulas infantis especiais, seja com medidas caseiras, tem eficácia semelhante no tratamento do refluxo gastroesofágico do lactente