BRAF V600E mutation is associated with aggressive features in papillary thyroid carcinomas ≤ 1.5 cm

Characteristics and Prognostic Markers of Aggressive Subtypes of Thyroid Cancer: A Retrospective Study

OBJECTIVE

The prevalence of thyroid cancer has increased significantly. Aggressive subtypes of papillary thyroid cancer (AG-PTC) and high-grade follicular cell-derived malignancies (HGFM) are malignancies that lie between well-differentiated and undifferentiated cancers, and their management needs to be clarified. The aim of our study is to describe the clinicopathological characteristics of AG-PTC and HGFM and to assess their prognostic value.

METHODS

This was a retrospective chart review study at single center of patients with AG-PTC or HGFM. HGFM comprised of patients with poorly differentiated thyroid cancer (PDTC) and differentiated high-grade thyroid carcinoma. The clinical presentation, pathological characteristics, molecular markers, specific treatments, and clinical outcomes were compared between the groups.

RESULTS

Of the 3244 thyroid cancer charts reviewed, 136 met the criteria for AG-PTC and HGFM. The mean age at diagnosis was 49 years, with a predominance of women. The median follow-up duration was 3 years. The rate of persistent or recurrent disease was 40.3% in the AG-PTC group and 29.3% in the HGFM group, 4.5% died in the AG-PTC group, and 1.8% died in the HGFM group. The presence of vascular, lymphovascular invasion and extrathyroidal extension were associated with a higher incidence of persistent or recurrent disease (Hazard ratio: 2.5, 3.8, and 4.2, respectively; p < 0.05). When the Ki-67 index was divided into five groups, the recurrence rate was higher in the ≥ 20% Ki-67 group.

CONCLUSIONS

Possible prognostic markers for predicting worse prognosis include vascular/lymphovascular invasion, extrathyroidal extension, and the proliferative index Ki-67.

Role of contrast-enhanced ultrasound with time-intensity curve analysis about thyroid nodule and parenchyma for differentiating BRAF V600E mutation status

Background

The BRAF V600E mutation was proven associated with papillary thyroid cancer (PTC) which has more aggressive behavior and could affect the outcome of PTC. The objective of this study was to observe more contrast-enhanced ultrasound (CEUS) time-intensity curve (TIC)-based quantitative parameters in nodules and surrounding parenchyma and analyze the association between the TIC-based quantitative parameters and BRAF V600E mutation status in patients with PTC.

Methods

A retrospective analysis of 447 PTC patients was conducted. Prior to thyroidectomy or fine needle aspiration (FNA), all patients had CEUS and had their BRAF V600E mutations examined. Based on their mutation status, the patients were split into two groups. The two groups were compared in terms of sex, age, quantitative CEUS characteristics, pathological findings, vascular invasion, capsular invasion, and cervical lymph node metastases.

Results

A total of 240 patients were in the mutation negative group and 207 patients were in the BRAF mutation positive group. The BRAF-positive group exhibited significantly higher arrival time (AT) and time to peak enhancement (TTP) of the nodules, among other direct quantitative characteristics. The BRAF-positive mutant nodules showed significantly higher arrival time change and time to peak change compared to the surrounding parenchyma for indirect quantitative metrics.

Conclusion

The time-dependent quantitative parameters of CEUS time intensity curve in nodules and surrounding parenchyma have clinical value in distinguishing BRAF V600E mutation positive nodules from gene mutation negative nodules. Quantitative CEUS characteristics may be beneficial in detecting the BRAF V600E mutation status and informing the subsequent clinical choice.

The Prevalence and Prognostic Implications of BRAF K601E Mutations in Thyroid Neoplasms: A Systematic Review and Meta-Analysis

BACKGROUND

Activating mutations in the BRAF oncogene occur in 45% of papillary thyroid carcinomas (PTCs). Though less studied, K601E may identify a clinically distinct subset of thyroid neoplasms.

METHODS

A bioinformatics assessment was conducted using the COSMIC database and in silico data analysis. A systematic search was conducted through August 2024 to identify studies reporting BRAF mutation in thyroid neoplasms. Pooled prevalence, histopathological subtype distribution, extrathyroidal extension, lymph node metastasis, recurrence, and survival were extracted/analyzed from 32 studies (13 191 patients).

RESULTS

In the COSMIC database, BRAF K601E was found in various tissue types but mainly in the thyroid. In silico data analysis revealed a structural and functional basis for differences between K601E and V600E. Upon systematic review, the BRAF K601E mutation was identified in 2.8% of PTCs compared to 22% with V600E. The stratified analysis revealed geographical differences, with higher rates in Italy (5.23%) and the United States of America (3.31%). The K601E mutant was enriched for follicular-patterned variants like NIFTP (11.2% of cases). Meta-analysis demonstrated significantly reduced extrathyroidal extension for K601E versus V600E mutants (RR = 0.22, 95% CI = 0.10-0.50, p = 0.0003).

CONCLUSION

K601E-mutated neoplasms could be a unique clinicopathological entity associated with low-risk histology and reduced extrathyroidal extension, consistent with a more indolent course than V600E mutants. Although detecting K601E may potentially guide conservative management, further prospective studies are needed.

Diffuse large B-cell lymphoma with BRAF V600E mutation mimicking thyroid carcinoma in fine-needle aspiration: A diagnostic pitfall

We report a rare case of thyroid diffuse large B-cell lymphoma with a BRAF V600E mutation, which mimics poorly differentiated thyroid cancer in fine needle aspiration cytology.

High aggressiveness of papillary thyroid cancer: from clinical evidence to regulatory cellular networks

The global incidence of thyroid cancer has increased over recent decades. Papillary thyroid cancer (PTC) is the most common type of thyroid cancer and accounts for nearly 90% of all cases. Typically, PTC has a good prognosis. However, some PTC variants exhibit more aggressive behaviour, which significantly increases the risk of postoperative recurrence. Over the past decade, the high metastatic potential of PTC has drawn the attention of many researchers and these studies have provided useful molecular markers for improved diagnosis, risk stratification and clinical approaches. The aim of this review is to discuss the progress in epidemiology, metastatic features, risk factors and molecular mechanisms associated with PTC aggressiveness. We present a detailed picture showing that epithelial-to-mesenchymal transition, cancer metabolic reprogramming, alterations in important signalling pathways, epigenetic aberrations and the tumour microenvironment are crucial drivers of PTC metastasis. Further research is needed to more fully elucidate the pathogenesis and biological behaviour underlying the aggressiveness of PTC.

Correlation analysis between BRAFV600E mutation and ultrasonic and clinical features of papillary thyroid cancer

Purpose

The study investigates the value of the BRAFV600E mutation in determining the aggressiveness of papillary thyroid cancer (PTC) and its correlation with ultrasound features.

Methods

The study selected 176 patients with BRAFV600E mutation and 80 without the mutation who underwent surgery at Guangxi Medical University Cancer Hospital. Clinical and pathological data were collected, focusing on BRAFV600E mutations and associated ultrasonic features. Correlation analysis, as well as univariate and multivariate logistic regression analysis, were conducted to identify independent risk factors for BRAFV600E mutation. The results were verified using a nomogram model.

Results

The analysis results indicate that the BRAFV600E mutation correlates with tumor size, nodule size, taller-than-wide shape, margin, and shape of papillary thyroid cancer. The receiver operating characteristic curve was used to analyze the diagnostic effect of these features on BRAFV600E mutation. The results showed that nodule size had the most significant area under the curve (AUC = 0.665). Univariate and multivariate logistic regression analyses revealed that taller-than-wide shape ≥1, ill-defined margin, irregular shape, nodule size (≤1.40 cm), TT4 (>98.67 nmol/L), and FT3 (<4.14 pmol/L) were independent risk factors for BRAFV600E mutation. While considering all these factors in the nomogram, the Concordance index (C-index) remained high at 0.764. This suggests that the model has a good predictive effect.

Conclusion

Ultrasound features including nodule size, taller-than-wide shape ≥1, ill-defined margins, irregular shape, higher TT4 levels, and lower FT3 levels were associated with papillary thyroid cancer aggressiveness and BRAFV600E mutation.

BRAFV600E mutation does not predict lymph node metastases and recurrence in Chinese papillary thyroid microcarcinoma patients

OBJECT

Previous studies suggest BRAFV600E mutation is a marker for poor prognosis in papillary thyroid cancer, however, its ability to further risk stratify papillary thyroid microcarcinoma (PTMC) remains controversial. We aimed to explore the association between BRAFV600E mutation and the clinicopathological features and recurrence in Chinese PTMC patients.

METHODS

We retrospectively reviewed 2094 PTMC patients who underwent surgery and had a valid BRAFV600E mutation test result. Among them, 1292 patients had complete follow-up data. The mutation incidence was determined. Moreover, the clinicopathological characteristics, disease-free survival (DFS), and response to therapy distribution were compared between the mutation and non-mutation groups.

RESULTS

BRAFV600E mutation was observed in 90.6 % of all patients and 89.2 % of patients with complete follow-up data. No significant difference was observed in lymph node metastases (LNM) number categories between the mutation and non-mutation groups among all patients (P = 0.329) and 1292 patients (P = 0.408). Neither the 3-year DFS (97.9 % vs. 98.0 %, P = 0.832) nor the response to therapy distribution (P > 0.05) indicated a significant difference between the mutation and non-mutation groups. The 3-year DFS differs among patients having different LNM number categories (99.8 % vs. 98.5 % vs. 77.3 %, P < 0.001). Multivariate analysis revealed that high-volume (over 5) LNM (Total thyroidectomy (TT): OR = 4.000, 95 % CI 2.390-6.694, P < 0.001; Unilateral thyroidectomy (UT): OR = 4.183, 95 % CI 1.565-11.190, P = 0.004), rather than BRAFV600E mutation (P > 0.05), was an independent risk factor of response to therapy.

CONCLUSIONS

Our results suggested that BRAFV600E mutation could not accurately predict LNM or the recurrence of Chinese PTMC patients. Moreover, high-volume LNM is significantly associated with PTMC prognosis.

Clinical and molecular features of progressive papillary thyroid microcarcinoma

In recent decades, the prevalence of thyroid cancer has risen substantially, with papillary thyroid microcarcinoma (PTMC) constituting over 50% of cases. Although most PTMCs exhibit indolent growth and a favorable prognosis, some present an increased risk of recurrence and an unfavorable prognosis due to high-risk characteristics such as lymph node metastasis, extrathyroidal extension, and distant metastasis. The early identification of clinically progressing PTMC remains elusive. In this review, the authors summarize findings from PTMC progression-related literature, highlighting that factors such as larger tumor size, cervical lymph node metastasis, extrathyroidal extension, younger age, higher preoperative serum thyroid-stimulating hormone levels, family history, and obesity positively correlate with PTMC progression. The role of multifocality in promoting PTMC progression; however, remains contentious. Furthermore, recent studies have shed light on the impact of mutations, such as BRAF and TERT mutations, on PTMC progression. Researchers have identified several mRNAs, noncoding RNAs, and proteins associated with various features of PTMC progression. Some studies propose that peripheral and tumor tissue-infiltrating immune cells could serve as biomarkers for the clinical progression of PTMC. Collectively, these clinical and molecular features offer a rationale for the early detection and the development of precision theranostic strategies of clinically progressive PTMC.

Thyroid cancer in Ecuador: A genetic variants review and a cross-sectional population-based analysis before and after COVID-19 pandemic

Objectives

The purpose of this study is to describe the genetic variants present in the Ecuadorian population and the incidence and mortality patterns of thyroid cancer in Ecuador from 2016 to 2021.

Methods

The present research constitutes a nationwide cross-sectional study encompassing all reported cases of thyroid cancer (C-73) in Ecuador from 2016 to 2021. Incidence rates were calculated based on the annual population at risk, considering factors such as ethnicity, sex, age group, and the geographic location of the incidence. All data was collected from the Hospital Discharge Statistics and the Statistical Registry of General Deaths Databases.

Results

Between 2016 and 2021, a total of 20,297 hospital admissions and 921 deaths attributed to thyroid cancer were reported in Ecuador. The incidence of thyroid cancer remained relatively stable from 2016 to 2019. However, there was a notable decrease in 2020, followed by an increase in 2021. Notably, thyroid cancer prevalence rates were found to be higher in highlands regions. Moreover, two genetic variants, the BRAFV600E and KITL678F, have been identified in the Ecuadorian population. It is noteworthy that women exhibited a higher susceptibility to thyroid cancer, being five times more likely than men to develop this condition.

Conclusion

Ecuador exhibits one of the highest global incidences of thyroid cancer. Consequently, describing the genetic variants and epidemiological characteristics of thyroid cancer is imperative for enhancing healthcare access and formulating evidence-based public health policies. This research contributes towards a comprehensive understanding of thyroid cancer in the Ecuadorian context, aiming to improve targeted interventions and health outcomes.

Relationship of Recurrence Rate with some Characteristics in Patients with Thyroid Carcinoma

Background

Determining the clinical and subclinical characteristics related to the recurrence status in patients with a thyroid carcinoma has great significance for prognosis, prediction of recurrence and monitoring of treatment outcomes. This study aimed to determine the association between recurrence rate and some characteristics in patients with thyroid carcinoma.

Patients and Methods

The study was conducted by descriptive method with longitudinal follow-up on 102 thyroid carcinoma patients at 103 Military Hospital, Hanoi, Vietnam, from July 2013 to December 2016.

Results

Univariate analysis showed that there was a relationship between the recurrence characteristics in the studied patients and the characteristics of lymph node metastasis (P = 0.026; OR = 15; 95% CI = 1.4-163.2) and BRAF V600E mutation status (P = 0.01; OR = 3.41; 95% CI = 1.31-8.88). When analysing the multivariable Logistic regression model, there was a positive correlation between the occurrence of BRAF V600E gene mutation (P = 0.032; OR = 17.649; 95% CI = 1.290-241.523) and male sex (P = 0.036; OR = 12.788; 95% CI = 1.185-137.961) and the occurrence of recurrence in study patients. The mean time to relapse was earlier in male patients than in female patients (P = 0.02). The mean time to relapse in patients with the BRAF V600E mutation (31.81 ± 1.14 months) was shorter than the mean time to relapse in the group without the mutation (57.82 ± 2.08 months) (P = 0.01). The group of patients with mutations in the BRAF V600E gene increased the risk of recurrence compared with the group without the mutation (HR = 9.14, P = 0.04).

Conclusion

There is a positive correlation between recurrence and masculinity, lymph node metastasis and the occurrence of BRAF V600E mutations in thyroid carcinoma patients.

Matrix Metalloproteinase 9/microRNA-145 Ratio: Bridging Genomic and Immunological Variabilities in Thyroid Cancer

Matrix metalloproteinase 9 (MMP9) and microRNA-145 (miR-145) have emerged as essential biomarkers in thyroid cancer progression and metastasis. However, their combined evaluation and clinical utility as a unified prognostic marker across diverse thyroid cancer subgroups remain unexplored. We investigated the diagnostic and prognostic value of the MMP9/miR-145 ratio in thyroid cancer, hypothesizing it may overcome inter-patient heterogeneity and serve as a versatile biomarker regardless of genetic mutations or autoimmune status. MMP9 and miR-145 expressions were analyzed in 175 paired papillary thyroid cancer (PTC) and normal tissues. Plasma levels were assessed perioperatively and longitudinally over 12-18 months in 86 matched PTC patients. The associations with clinicopathological parameters and patient outcomes were evaluated. MMP9 was upregulated, and miR-145 downregulated in cancer tissues, with a median MMP9/miR-145 ratio 17.6-fold higher versus controls. The tissue ratio accurately diagnosed thyroid malignancy regardless of BRAF mutation or Hashimoto's thyroiditis status, overcoming genetic and autoimmune heterogeneity. A high preoperative circulating ratio predicted aggressive disease features, including lymph node metastasis, extrathyroidal extension, progression/relapse, and recurrence. Although the preoperative plasma ratio was elevated in patients with unfavorable outcomes, it had limited utility for post-surgical monitoring. In conclusion, the MMP9/miR-145 ratio is a promising biomarker in PTC that bridges genetic and immunological variabilities, enhancing preoperative diagnosis and prognostication across diverse patient subgroups. It accurately stratifies heterogenous cases by aggressiveness. The longitudinal trends indicate decreasing applicability for post-thyroidectomy surveillance. Further large-scale validation and protocol standardization can facilitate clinical translation of the MMP9/miR-145 ratio to guide personalized thyroid cancer management.

Developing Models to Predict BRAFV600E and RAS Mutational Status in Papillary Thyroid Carcinoma Using Clinicopathological Features and pERK1/2 Immunohistochemistry Expression

The Cancer Genome Atlas (TCGA) has classified papillary thyroid carcinoma (PTC) into indolent RAS-like and aggressive BRAF-like based on its distinct driver gene mutations. This retrospective study aimed to assess clinicopathology and pERK1/2 expression variations between BRAF-like and RAS-like PTCs and establish predictive models for BRAFV600E and RAS-mutated PTCs. A total of 222 PTCs underwent immunohistochemistry staining to assess pERK1/2 expression and Sanger sequencing to analyze the BRAF and RAS genes. Multivariate logistic regression was employed to develop prediction models. Independent predictors of the BRAFV600E mutation include a nuclear score of 3, the absence of capsules, an aggressive histology subtype, and pERK1/2 levels exceeding 10% (X2 = 0.128, p > 0.05, AUC = 0.734, p < 0.001). The RAS mutation predictive model includes follicular histology subtype and pERK1/2 expression > 10% (X2 = 0.174, p > 0.05, AUC = 0.8, p < 0.001). We propose using the prediction model concurrently with four potential combination group outcomes. PTC cases included in a combination of the low-BRAFV600E-scoring group and high-RAS-scoring group are categorized as RAS-like (adjOR = 4.857, p = 0.01, 95% CI = 1.470-16.049). PTCs included in a combination of the high-BRAFV600E-scoring group and low-RAS-scoring group are categorized as BRAF-like PTCs (adjOR = 3.091, p = 0.001, 95% CI = 1.594-5.995). The different prediction models indicate variations in biological behavior between BRAF-like and RAS-like PTCs.

Changes in antioxidant status and DNA repair capacity are corroborated with molecular alterations in malignant thyroid tissue of patients with papillary thyroid cancer

Introduction: Papillary thyroid cancer (PTC) accounts for approximately 80% of all thyroid cancer cases. The mechanism of PTC tumourigenesis is not fully understood, but oxidative imbalance is thought to play a role. To gain further insight, this study evaluated antioxidant status, DNA repair capacity and genetic alterations in individuals diagnosed with benign thyroid lesion in one lobe (BTG) and PTC lesion in another. Methods: Individuals with coexisting BTG and PTC lesions in their thyroid lobes were included in this study. Reactive oxygen species (ROS) level, ABTS radical scavenging activity, ferric reducing antioxidant capacity, glutathione peroxidase and superoxide dismutase activities were measured in the thyroid tissue lysate. The expression of selected genes and proteins associated with oxidative stress defence and DNA repair were analysed through quantitative real-time PCR and Western blotting. Molecular alterations in genomic DNA were analysed through whole-exome sequencing and the potentially pathogenic driver genes filtered through Cancer-Related Analysis of Variants Toolkit (CRAVAT) analysis were subjected to pathway enrichment analysis using Metascape. Results: Significantly higher ROS level was detected in the PTC compared to the BTG lesions. The PTC lesions had significantly higher expression of GPX1, SOD2 and OGG1 but significantly lower expression of CAT and PRDX1 genes than the BTG lesions. Pathway enrichment analysis identified "regulation of MAPK cascade," "positive regulation of ERK1 and ERK2 cascade" and "negative regulation of reactive oxygen species metabolic process" to be significantly enriched in the PTC lesions only. Four pathogenic genetic variants were identified in the PTC lesions; BRAF V600E, MAP2K7-rs2145142862, BCR-rs372013175 and CD24 NM_001291737.1:p.Gln23fs while MAP3K9 and G6PD were among 11 genes that were mutated in both BTG and PTC lesions. Conclusion: Our findings provided further insight into the connection between oxidative stress, DNA damage, and genetic changes associated with BTG-to-PTC transformation. The increased oxidative DNA damage due to the heightened ROS levels could have heralded the BTG-to-PTC transformation, potentially through mutations in the genes involved in the MAPK signalling pathway and stress-activated MAPK/JNK cascade. Further in-vitro functional analyses and studies involving a larger sample size would need to be carried out to validate the findings from this pilot study.

Beyond EGFR inhibitors in advanced colorectal cancer: Targeting BRAF and HER2

The addition of antiepidermal growth factor receptor (EGFR) monoclonal antibodies, cetuximab or panitumumab, to conventional chemotherapy has improved clinical outcomes for rat sarcoma virus (RAS) wild-type advanced colorectal cancer patients, however, durable responses and 5-year overall survival rates remain limited. BRAF V600E somatic mutation and human epidermal growth factor receptor (HER2) amplification/overexpression have been separately implicated in primary resistance to anti-EGFR therapeutic strategies via aberrant activation of the mitogen-activated protein kinase (MAPK) signaling pathway, resulting in poorer outcomes. In addition to being a negative predictive biomarker for anti-EGFR therapy, BRAF V600E mutation and HER2 amplification/overexpression serve as positive predictors of response to therapies targeting these respective tumor promoters. This review will highlight key clinical studies that support the rational use of v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) and HER2-targeted therapies, often in combination with other targeted agents, cytotoxic chemotherapy, and immune checkpoint inhibitors. We discuss current challenges with BRAF and HER2-targeted therapies in metastatic colorectal cancer and potential opportunities for improvement.

Low-Density Lipoprotein Receptor Is a Key Driver of Aggressiveness in Thyroid Tumor Cells

We previously described the role of low-density lipoprotein (LDL) in aggressiveness in papillary thyroid cancer (PTC). Moreover, the MAPK signaling pathway in the presence of BRAF V600E mutation is associated with more aggressive PTC. Although the link between MAPK cascade and LDL receptor (LDLR) expression has been previously described, it is unknown whether LDL can potentiate the adverse effects of PTC through it. We aimed to investigate whether the presence of LDL might accelerate the oncogenic processes through MAPK pathway in presence or absence of BRAF V600E in two thyroid cell lines: TPC1 and BCPAP (wild-type and BRAF V600E, respectively). LDLR, PI3K-AKT and RAS/RAF/MAPK (MEK)/ERK were analyzed via Western blot; cell proliferation was measured via MTT assay, cell migration was studied through wound-healing assay and LDL uptake was analyzed by fluorometric and confocal analysis. TPC1 demonstrated a time-specific downregulation of the LDLR, while BCPAP resulted in a receptor deregulation after LDL exposition. LDL uptake was increased in BCPAP over-time, as well as cell proliferation (20% higher) in comparison to TPC1. Both cell lines differed in migration pattern with a wound closure of 83.5 ± 9.7% after LDL coculture in TPC1, while a loss in the adhesion capacity was detected in BCPAP. The siRNA knockdown of LDLR in LDL-treated BCPAP cells resulted in a p-ERK expression downregulation and cell proliferation modulation, demonstrating a link between LDLR and MAPK pathway. The modulation of BRAF-V600E using vemurafenib-impaired LDLR expression decreased cellular proliferation. Our results suggest that LDLR regulation is cell line-specific, regulating the RAS/RAF/MAPK (MEK)/ERK pathway in the LDL-signaling cascade and where BRAF V600E can play a critical role. In conclusion, targeting LDLR and this downstream signaling cascade, could be a new therapeutic strategy for PTC with more aggressive behavior, especially in those harboring BRAF V600E.

Identification of crucial genes involved in thyroid cancer development

BACKGROUND

A malignancy of the endocrine system, one of the most common types, is thyroid cancer. It is proven that children who receive radiation treatment for leukemia or lymphoma are at a heightened risk of thyroid cancer due to low-dose radiation exposure throughout childhood. Several factors can increase the risk of thyroid cancer (ThyCa), such as chromosomal and genetic mutations, iodine intake, TSH levels, autoimmune thyroid disorders, estrogen, obesity, lifestyle changes, and environmental contaminants.

OBJECTIVES

The study aimed to identify a specific gene as an essential candidate for thyroid cancer progression. We might be able to focus on developing a better understanding of how thyroid cancer is inherited.

METHODS

The review article uses electronic databases such as PubMed, Google Scholar, Ovid MEDLINE, Embase, and Cochrane Central. The most frequently associated genes with thyroid cancer found on PubMed were BAX, XRCC1, XRCC3, XPO5, IL-10, BRAF, RET, and K-RAS. To perform an electronic literature search, genes derived from DisGeNET: a database of gene-disease associations, including PRKAR1A, BRAF, RET, NRAS, and KRAS, are used.

CONCLUSION

Examining the genetics of thyroid cancer explicitly emphasizes the primary genes associated with the pathophysiology of young and older people with thyroid cancer. Developing such gene investigations at the beginning of the thyroid cancer development process can identify better outcomes and the most aggressive thyroid cancers.

Association of DNA Promoter Methylation and BRAF Mutation in Thyroid Cancer

The BRAF V600E mutation and DNA promoter methylation play important roles in the pathogenesis of thyroid cancer (TC). However, the association of these genetic and epigenetic alterations is not clear. In this study, using paired tumor and surrounding normal tissue from the same patients, on a genome-wide scale we tried to identify (a) any association between BRAF mutation and DNA promoter methylation, and (b) if the molecular findings may provide a basis for therapeutic intervention. We included 40 patients with TC (female = 28, male = 12) without distant metastasis. BRAF mutation was present in 18 cases. We identified groups of differentially methylated loci (DML) that are found in (a) both BRAF mutant and wild type, (b) only in BRAF mutant tumors, and (c) only in BRAF wild type. BRAF mutation-specific promoter loci were more frequently hypomethylated, whereas BRAF wild-type-specific loci were more frequently hypermethylated. Common DML were enriched in cancer-related pathways, including the mismatch repair pathway and Wnt-signaling pathway. Wild-type-specific DML were enriched in RAS signaling. Methylation status of checkpoint signaling genes, as well as the T-cell inflamed genes, indicated an opportunity for the potential use of PDL1 inhibitors in BRAF mutant TC. Our study shows an association between BRAF mutation and methylation in TC that may have biological significance.

Identification of KIT and BRAF mutations in thyroid tissue using next-generation sequencing in an Ecuadorian patient: A case report

Background

The incidence of thyroid cancer has increased worldwide. Ecuador presents the highest incidence among Latin American countries and the second around the world. Genetic alteration is the driving force for thyroid tumorigenesis and progression. The change from valine (V) to glutamic acid (E) at codon 600 of the BRAF gene (BRAF^Val600Glu) is the most commonly reported mutation in thyroid cancer. Moreover, the BRAF mutation is not the only mutation that has been correlated with TC. For instance, mutations and overexpression of the KIT gene has been associated with different types of cancer, including lung and colon cancer, and neuroblastoma.

Case presentation

A woman in her early fifties, self-identified as mestizo, from Otavalo, Imbabura-Ecuador had no systemic diseases and denied allergies, but she had a family history of a benign thyroid nodule. Physical examination revealed a thyroid gland enlargement. The fine-needle aspiration biopsy indicated papillary thyroid cancer. The patient underwent a successful total thyroidectomy with an excellent recovery and no additional treatments after surgery. Using Next-Generation sequencing a heterozygous mutation in the BRAF gene, causing an amino acid change Val600Glu was identified. Similarly, in the KIT gene, a heterozygous mutation resulting in an amino acid change Leu678Phe was detected. Moreover, an ancestry analysis was performed, and the results showed 3.1% African, 20.9% European, and 76% Native American ancestry.

Conclusions

This report represents the genetic characteristics of papillary thyroid cancer in an Ecuadorian woman with a mainly Native American ethnic component. Further studies of pathological variants are needed to determine if the combined demographic and molecular profiles are useful to develop targeted treatments focused on the Ecuadorian population.

Younger Than 55 Years Old and BRAF V600E Mutation are Risk Factors for Lymph Node Metastasis in Papillary Thyroid Carcinomas ≤1.0 cm but Not in >1.0 cm

Background

Studies on the relationship between BRAF V600E mutation and the clinicopathologic features of papillary thyroid carcinoma (PTC), risk of lymph node metastasis in papillary thyroid microcarcinoma (PTMC) have shown inconsistent results.

Methods

In this retrospective analysis, clinicopathological data of the patients were collected, and molecular testing was done for BRAF V600E mutation. PTC patients are divided into PTC≤1.0cm (PTMC) and PTC>1.0cm, and the relationship between BRAF V600E mutation and clinicopathologic features was analyzed respectively.

Results

Of the 520 PTC patients, 432 (83.1%) were female and 416 (80.0%) were <55 years old. BRAF V600E mutation was detected in 422 (81.2%) tumour samples of PTC. There was no significant difference in the frequency of BRAF V600E mutation between different age groups. There were 250 (48.1%) patients with PTMC and 270 (51.9%) patients with PTC>1.0cm. BRAF V600E mutation was significantly associated with bilateral cancer (23.0% vs 4.9%, P=0.005) and lymph node metastasis (61.7% vs 39.0%, P=0.009) in PTMC patients, while BRAF V600E mutation was significantly associated with bilateral cancer (24.9% vs 12.3%, P=0.048) in PTC>1.0cm patients. Logistic regression analysis showed that, after adjusting for gender, Hashimoto's thyroiditis and calcification, we found that younger age (<55 years old) (OR: 2.384, 95% CI: 1.241-4.579, P=0.009) and BRAF V600E mutation (OR: 2.213, 95% CI: 1.085-4.512, P=0.029) were significantly associated with lymph node metastasis in PTMC, similar results were not obtained in PTC>1.0cm.

Conclusion

Younger age (<55 years old) and BRAF V600E mutation was independent risk factor for lymph node metastasis in PTMC.

Iodine nutrition and papillary thyroid cancer

Thyroid cancer (TC) is the most frequent endocrine malignancy. The incidence of TC, especially papillary thyroid carcinoma (PTC), has continued to rise all over the world during the past few years, for reasons that are not entirely clear. Though the phenomenon of overdiagnosis is occurring, it is not the sole driver of the substantial increase in incidence. Lifestyle, environmental factors, or complications are considered to be potential risk factors. Among these factors, iodine is a micronutrient that is vital to thyroid function. The effect of iodine intake on PTC has been controversial for many years and the epidemiological or experimental studies provided diametrically opposite conclusions. Combining all these studies, we found that iodine nutrition may affect the overall prevalence, distribution of the histological types, and clinicopathological aggressiveness of TC, especially PTC. However, the available evidence is poor due to the impact of various internal and external related factors. Therefore, this article sums up available results from both epidemiological and experimental studies, future studies are also warranted to expound on the relationship between overall PTC prevalence and iodine intake.

A Potential Four-Gene Signature and Nomogram for Predicting the Overall Survival of Papillary Thyroid Cancer

Background. Although the prognosis of papillary thyroid cancer (PTC) is relatively good, some patients experience recurrence or distant metastasis after thyroidectomy and progress to radioactive iodine refractory stage. Therefore, accurate prediction of clinical outlook can aid to screen out the minority of patients with poorer prognosis and avoid excessive treatment in low-risk patients. Methods. The RNA-seq and clinical data of PTC patients was downloaded from the Gene Expression Omnibus (GEO) and the Cancer Genome Atlas (TCGA) databases. Multivariate and Lasso Cox regression analyses were used to construct a prognostic nomogram to predict overall survival (OS). Thereafter, quantitative RT-PCR and Human Protein Atlas (HPA) database were employed to verify the expression of key genes. Results. A four-gene risk score comprising ABI3BP, DPT, MRO, and TENM1 was exhibited strong prognostic value. Moreover, an integrated nomogram was established based on the risk score, age, AJCC (American Joint Commission on Cancer) stage, tumor size, extrathyroidal extension, and history of neoadjuvant treatment, which exhibited significantly better predictive performance than TNM stage system ( $P<0.05$ ). GSEA (Gene Set Enrichment Analysis) and GSVA (Gene Set Variation Analysis) revealed that the different tumor-associated hallmarks, biological processes, and pathways were substantially enriched in the poor-prognosis group. In addition, a ceRNA network was constructed by including the four genes (ABI3BP, DPT, MRO, and TENM1), 54 lncRNAs, and 10 miRNAs. Finally, both the relative mRNA and protein expression of ABI3BP, DPT, MRO, and TENM1 were validated. Conclusion. The present study identified a four-gene risk signature and developed a novel nomogram, which could be regarded as a reliable prognostic model for PTC patients. The findings also revealed preliminary potential mechanisms that may influence the prognosis outcome. These results can be conducive to design personalized treatment and prognosis management in affected patients.

Molecular Testing for Thyroid Nodules: The Experience at McGill University Teaching Hospitals in Canada

In the past few decades, molecular characterization of thyroid cancer has made significant progress and is able to identify thyroid-cancer-related molecular markers that can then be applied clinically for improved decision making. The aim of this review is to provide a general overview about the molecular markers (mutations and alterations) of thyroid cancers, present several molecular tests, and discuss the clinical applications of identifying these markers supported by the clinical experience of several high-volume thyroid cancer specialists at the McGill university hospitals in Montreal, Canada. Our group experience showed that molecular testing can reclassify more than half of the patients with indeterminate thyroid nodules (Bethesda III and IV) into benign and spare these patients from unnecessary diagnostic surgery. Furthermore, it can help optimize the initial management in thyroid cancers with no evidence of high risk of recurrence of disease preoperatively. While routine molecular testing is not firmly established for thyroid FNA specimens that are suspicious or positive for malignancy (Bethesda V and VI), knowledge of a thyroid nodule’s molecular risk group profile in such cases, together with its clinical and radiologic features, can help select the optimal surgical options (lobectomy versus upfront total thyroidectomy and central neck dissection), as demonstrated by our studies.