Clinicopathological significance of TERT promoter mutation in papillary thyroid carcinomas: a systematic review and meta-analysis

The impact of C216T and hot spot mutations of the TERT promoter on the clinicopathologic characteristics and S100A10 expression in papillary thyroid carcinoma: a comparative study

OBJECTIVE

The C216T mutation in the TERT promoter (TERTp) is a rarely reported genetic alteration in papillary thyroid carcinoma (PTC). Its clinical significance remains unclear. This study aimed to compare the impact of the C216T and hot spot mutations (C228T and C250T) of TERTp on the clinicopathologic characteristics and the expression of S100A10, a member of the S100 protein family, in PTC.

METHODS

In this retrospective study, a cohort comprising 8 PTC cases with the C216T mutation, 12 cases with the hot spot mutations, and 120 cases with the wildtype genotype was established. The influence of TERTp mutations on the clinicopathologic profiles of PTC was assessed.

RESULTS

The C216T mutation was mutually exclusive with the hot spot mutations and its frequency (0.19%) fell between that of C228T (0.68%) and C250T (0.06%). Compared to PTC cases with the wildtype genotype, cases with C216T mutations did not exhibit significant differences in clinicopathologic characteristics and S100A10 expression levels. In contrast, the hot spot mutations were positively associated with extrathyroidal extension (p = 0.001), ATA recurrence risk (p < 0.001), AJCC staging (p < 0.001), and increased expression of S100A10 (p = 0.005). Furthermore, a significant correlation was found between S100A10 expression and extrathyroidal extension (p = 0.005), lymph node metastasis (p = 0.013), and ATA recurrence risk (p = 0.023).

CONCLUSION

The C216T mutation did not induce the aggressiveness of PTC as the hot spot mutations did. Furthermore, the hot spot mutations were closely associated with the increased expression of S100A10. The latter may contribute to the pro-invasive effect of the hot spot mutations on PTC.

Association Between Gross Features and Coexistence of BRAFV600E and TERT Promoter Mutations in Papillary Thyroid Carcinomas: A Combined Analysis Incorporating Clinicopathologic Features

Background: The coexistence of v-Raf murine sarcoma viral oncogene homolog B1 (BRAFV600E) and telomere reverse transcriptase promoter (TERT-p) mutations is considerably associated with aggressiveness and poor prognosis in papillary thyroid carcinoma (PTC). However, the association between gross findings and genetic alterations in PTC remains unknown. We aimed to investigate the association between clinicopathologic features, including macroscopic features, and the coexistent BRAFV600E and TERT-p mutations in patients with PTC. Methods: We retrospectively analyzed 375 cases of PTC surgically resected between January 2018 and October 2023 at a single institution, based on the presence of BRAFV600E and TERT-p double mutation. Clinicopathologic features, including gross features on the cut surface of tumors, were evaluated. Subsequently, the association between clinicopathologic features and mutation status was statistically examined. Cox proportional hazard models were used to analyze the impact of molecular pathological features on disease-free survival (DFS). Results: The BRAFV600E and TERT-p double mutation was identified in 78 (20.8%) patients among the PTC cases and was significantly correlated with shorter DFS. Multivariable analysis revealed that factors such as relatively older age (≥55 years) (odds ratio [OR] = 12.083, 95% confidence interval [CI] 4.498-32.456), larger tumor size (>2.0 cm) (OR = 2.722, CI 1.104-6.712), lobulated tumor margins (OR = 16.114, CI 3.155-82.296), papillary excrescences on the cut surface (OR = 17.573, CI 3.462-89.201), solid-cut surface (OR = 4.012, CI 1.084-14.849), minimal extrathyroidal extension (ETE) (OR = 4.156, CI 1.209-14.282), gross ETE (OR = 6.517, CI 1.734-24.490), and Ki-67 labeling index (LI) (≥5%, OR = 12.145, CI 4.354-33.877) were significantly associated with the double mutation. Conclusions: The BRAFV600E and TERT-p double mutation in PTC was significantly associated with relatively old age, larger tumor size, lobulated configuration in tumor margin, papillary excrescences on the cut surface, solid-cut surface, ETE, and high Ki-67 LI. These features are suggestive of the presence of the double mutation and should be analyzed at the molecular level in patients with PTC.

Clinical features combined with ultrasound characteristics to predict TERT promoter mutations in papillary thyroid carcinoma: a single-center study over the past 5 years

Purpose

Telomerase reverse transcriptase (TERT) has been reported in papillary thyroid carcinoma (PTC). This study aimed to investigate the correlation of TERT promoter mutations with clinical and ultrasound (US) features in PTC and to develop a model to predict TERT promoter mutations.

Methods

Preoperative US images, postoperative pathological features, and TERT promoter mutation information were evaluated in 365 PTC patients confirmed by surgery. Univariate and multivariate factor analyses were performed to identify risk factors for TERT promoter mutations. A predictive model was established to assess the clinical predictive value.

Results

Of the 365 patients with PTC (498 nodules), the number of those with TERT promoter mutations was 67 cases (75 nodules), and the number of those without mutations was 298 cases (423 nodules). The median age was 40 years in the wild-type group and 60 years in the mutant group. Male patients made up 35.82% of the mutant group and 22.82% of the wild-type group. Multivariate analysis revealed that the independent risk factors associated with the occurrence of TERT promoter mutation in PTC were as follows: older age (odds ratio (OR) = 1.07; p = 0.002), maximum diameter of ≥ 10 mm (OR = 3.94; p < 0.0001), unilateral (OR = 4.15; p < 0.0001), multifocal (OR = 7.69; p < 0.0001), adjacent to the thyroid capsule (OR = 1.94; p = 0.044), and accompanied by other benign nodules (OR = 1.94, p = 0.039). A predictive model was established, and the area under the curve (AUC) of the receiver operating characteristic was 0.839. TERT promoter mutations were associated with high-risk US and clinical features compared with the wild-type group.

Conclusion

TERT promoter mutations were associated with older ages. They were also found to be multifocal, with a maximum diameter of ≥ 10 mm, unilateral, adjacent to the thyroid capsule, and accompanied by other benign nodules. The predictive model was of high diagnostic value.

Gene mutations as predictors of central lymph mode metastasis in cN0 PTC: A meta-analysis

Gene mutations could predict the tumor progression and prognosis, which are us to predict CLNM in patients with cN0 PTC, however, these results are not consistent. This meta-analysis tried to identify gene mutations which could predict CLNM in patients with cN0 PTC. A systematic search was performed for identifying relevant literature published prior to July 2023 in three search engines: PubMed, EMBASE and Web of Science. Studies that investigated the gene mutations for CLNM in patients with cN0 PTC were included in our meta-analysis. Sixteen studies, including 6095 cN0 PTC with BRAF mutations were include in our meta-analysis. The prevalence of CLNM in cN0 PTC ranged from 13.7% to 50.6%. The pooled analysis demonstrated that BRAFV600E mutation is significantly associated with CLNM (OR = 2.01, 95% CI: 1.55-2.60, p < 0.001) in PTC and PTMC (OR = 1.70, 95% CI: 0.51-1.81, p < 0.001). Whereas, cN0 PTC with TERT (OR = 1.94, 95% CI: 0.51-7.36, p = 0.33) and KRAS (OR = 0.57, 95% CI: 0.51-1.81, p = 0.34) mutations might not contribute to predict CLNM. Our analysis identified that BRAF mutation was a predictive factor for cN0 PTC, as well as for cN0 PTMC, which could be useful for clinician to accurately choose prophylactic CLND and better manage cN0 PTC.

Clinical relevance of gene mutations and rearrangements in advanced differentiated thyroid cancer

BACKGROUND

Tumor genotyping is becoming crucial to optimize the clinical management of patients with advanced differentiated thyroid cancer (DTC); however, its implementation in clinical practice remains undefined. We herein report our single-center experience on molecular advanced DTC testing by next-generation sequencing approach, to better define how and when tumor genotyping can assist clinical decision making.

MATERIALS AND METHODS

We retrospectively collected data on all adult patients with advanced DTC who received molecular profiling at the IRCSS Sant'Orsola-Malpighi Hospital from 2008 to 2022. The genetic alterations were correlated with radioactive iodide refractory (RAI-R), RAI uptake/disease status, and time to RAI resistance (TTRR) development.

RESULTS

A significant correlation was found between RAI-R development and genetic alterations (P = 0.0001). About 48.7% of RAI-R cases were positive for TERT/TP53 mutations (as both a single event and comutations with other driver gene alterations, such as BRAF mutations, RAS mutations, or gene fusions), while the great majority of RAI-sensitive cases carried gene fusions (41.9%) or were wild type (WT; 41.9%). RAI uptake/disease status and time to TTRR were significantly associated with genetic alterations (P = 0.0001). In particular, DTC with TERT/TP53 mutations as a single event or as comutations displayed a shorter median TTRR of 35.4 months (range 15.0-55.8 months), in comparison to the other molecular subgroups. TERT/TP53 mutations as a single event or as comutations remained independently associated with RAI-R after Cox multivariate analysis (hazard ratio 4.14, 95% CI 1.51-11.32; P = 0.006).

CONCLUSIONS

Routine testing for genetic alterations should be included as part of the clinical workup, for identifying both the subset of more aggressive tumors and the subset of tumors harboring actionable gene fusions, thus ensuring the appropriate management for all patients with advanced DTC.

TERT and BRAF V600E mutations in thyroid cancer of World Trade Center Responders

The 2-fold excess thyroid cancer risk reported in multiple World Trade Center (WTC) disaster exposed cohorts cannot entirely be explained by surveillance and physician bias thus highlighting the need to investigate the potential consequences of the dust exposure, containing carcinogenic and endocrine disruptive elements, on the thyroid. This study investigated the presence of TERT promoter and BRAF V600E mutations in 20 WTC-exposed versus 23 matched non-exposed thyroid cancers as potential mechanism explaining the excess risk. Although no significant difference in BRAF V600E mutation was found, TERT promoter mutations were significantly more prevalent in WTC thyroid cancer versus non-exposed thyroid cancers (P = 0.021). The odds of a TERT promoter mutation was significantly higher in the WTC versus the non-WTC thyroid cancers after adjustment [ORadj: 7.11 (95% CI: 1.21-41.83)]. These results may indicate that exposure to the mixture of pollutants present in the WTC dust resulted in an excess thyroid cancer risk and potentially more aggressive thyroid cancer, warranting investigating WTC responders on thyroid-associated symptoms during their health checkups. Future studies should include long-term follow-up to provide important insights in whether thyroid-specific survival is negatively affected by WTC dust exposure and whether this is because of the presence of one or more driver mutations.

Investigation of the mechanism of Prunella vulgaris in treatment of papillary thyroid carcinoma based on network pharmacology integrated molecular docking and experimental verification

To analyze the molecular mechanism of Prunella vulgaris L. (PV) in the treatment of papillary thyroid carcinoma (PTC) by using network pharmacology combined with molecular docking verification. Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database was used to predict the main active components of PV, Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, PubChem, and Swiss Target Prediction databases were used to obtain the corresponding targets of all active components. Targets collected for PTC treatment through Gene Cards, Digest and Online Mendelian Inheritance in Man databases respectively. The Search Tool for the Retrieval of Interaction Gene/Protein database was used to obtain the interaction information between proteins, and the topology analysis and visualization were carried out through Cytoscape 3.7.2 software (https://cytoscape.org/). The R package cluster profiler was used for gene ontology and Kyoto encyclopedia of genes and genomes analysis. The "active ingredient-target-disease" network was constructed by using Cyto scape 3.7.2, and topological analysis was carried out to obtain the core compound. The molecular docking was processed by using Discovery Studio 2019 software, and the core target and active ingredient were verified. The inhibition rate was detected by CCK8 method. Western blot was used to detect the expression levels of kaempferol anti-PTC related pathway proteins. A total of 11 components and 83 corresponding targets in the component target network of PV, of which 6 were the core targets of PV in the treatment of PTC. It was showed that quercetin, luteolin, beta (β)-sitosterol, kaempferol may be the core components of PV in the treatment of PTC. vascular endothelial growth factor A, tumor protein p53, transcription factor AP-1, prostaglandin endoperoxidase 2, interleukin 6, and IL-1B may be important targets for the treatment of PTC. The main biological processes mainly including response to nutrient levels, response to xenobiotic stimulus, response to extracellular stimulus, external side of plasma membrane, membrane raft, membrane microdomain, serine hydrolase activity, serine-type endopeptidase activity, antioxidant activity, etc IL-17 signaling pathway, and PI3K-Akt signaling pathway may affect the recurrence and metastasis of PTC. Kaempferol may significantly reduce the activity of Papillary cells of human thyroid carcinoma bcpap cell lines cells compared with quercetin, luteolin, β-sitosterol. Kaempferol may reduce the protein expression levels of interleukin 6, vascular endothelial growth factor A, transcription factor AP-1, tumor protein p53, 1L-1B and prostaglandin endoperoxidase 2, respectively. PV has the characteristics of multi-components, multi-targets and multi- pathways in the treatment of PTC, which network pharmacology help to provides a theoretical basis for the screening of effective components of PV and further research.

TERT genetic polymorphism rs2736100 is associated with an aggressive manifestation of papillary thyroid carcinoma

Objectives

TERT rs2736100 genetic polymorphism is commonly found in human malignancies, indicating its key role in cancer cell transformation. The aim of this study is to investigate the effects of the functional TERT rs2736100 genetic polymorphism on the outcomes of papillary thyroid carcinoma (PTC) patients.

Materials and methods

We performed a retrospective study on the relationship between rs2736100 and clinicopathological outcomes of PTC in 500 patients (378 females and 122 males) aged 43.8 ± 11.4 years (range 15-74 years) with a median follow-up of 60 months (range, 1-455 months).

Results

TERT rs2736100 genetic polymorphism (TG/GG vs. TT) was significantly associated with several high-risk clinicopathological features such as tumor spread, extrathyroidal extension, central/lateral lymph node metastases, and Stage T III or IV disease. However, in Kaplan-Meier survival analyses, the rs2736100 mutation was unrelated to overall disease-free survival with a log-rank value of p > 0.05. In Cox-regression analyses, the overall survival rate of recurrence/neo-metastasis was related to a larger tumor size, younger age, and tumor spread but unrelated to the rs2736100 mutation.

Conclusions and significance

TERT rs2736100 genetic polymorphism mutation is more likely to manifest with aggressive clinicopathological characteristics but cannot worsen prognosis in PTC.

Effect of Having Concurrent Mutations on the Degree of Aggressiveness in Patients with Thyroid Cancer Positive for TERT Promoter Mutations

This study aimed to examine whether concurrent mutations with a TERT promoter mutation are associated with a greater likelihood of more aggressive disease than a TERT promoter mutation alone. The medical records of 1477 patients who underwent thyroid surgery at two tertiary hospitals between 2017 and 2022 were reviewed. Twenty-four patients had TERT promoter mutations based on molecular profile testing. Clinicodemographic data, mutational profiles, and histopathological features were assessed. Descriptive analysis, Fisher's exact test, and binary logistic regression were performed. Seven patients had single-gene TERT promoter mutations, and 17 had concurrent mutations, including BRAF V600E, HRAS, NRAS, PIK3CA, and EIF1AX. The overall prevalence of malignancy was 95.8%, of which 78.3% were aggressive thyroid cancers. There was a statistically significant association between concurrent mutations and disease aggressiveness. The odds of having aggressive disease were 10 times higher in patients with a TERT promoter mutation and a concurrent molecular alteration than in those with a TERT promoter mutation alone. This is an important finding for thyroid specialists to consider when counseling patients concerning risk stratification and management options.

A clinical and molecular pathology prediction model for central lymph node metastasis in cN0 papillary thyroid microcarcinoma

BACKGROUND

The frequency of thyroid cancer has rapidly increased in recent years globally. Thus, more papillary thyroid microcarcinoma (PTMC) patients are being diagnosed, including clinical lymph node-negative (cN0) patients. Our study attempted to develop a prediction model for assessing the probability of central lymph node metastasis (CLNM) in cN0 PTMC patients.

METHODS

A total of 595 patients from the Affiliated Hospital of Qingdao University (training cohort: 456 patients) and the Affiliated Hospital of Jining Medical University (verification cohort: 139 patients) who underwent thyroid surgery between January 2020 and May 2022 were enrolled in this study. Their clinical and molecular pathology data were analyzed with multivariate logistic regression to identify independent factors, and then we established a prediction model to assess the risk of CLNM in cN0 PTMC patients.

RESULTS

Multivariate logistic regression analysis revealed that sex, Hashimoto's thyroiditis (HT), tumor size, extrathyroidal extension, TERT promoter mutations and NRAS mutation were independent factors of CLNM. The prediction model demonstrated good discrimination ability (C-index: 0.757 and 0.753 in the derivation and validation cohorts, respectively). The calibration curve of the model was near the optimum diagonal line, and decision curve analysis (DCA) showed a noticeably better benefit.

CONCLUSION

CLNM in cN0 PTMC patients is associated with male sex, tumor size, extrathyroidal extension, HT, TERT promoter mutations and NRAS mutation. The prediction model exhibits good discrimination, calibration and clinical usefulness. This model will help to assess CLNM risk and make clinical decisions in cN0 PTMC patients.

Risk Factors for TERT Promoter Mutations with Papillary Thyroid Carcinoma Patients: A Meta-Analysis and Systematic Review

Whether TERT promoter mutation is related to more aggressive clinicopathologic features and worse outcomes in papillary thyroid carcinoma patients (PTCs) is still variable and controversial. Our intention was to investigate the risk or prognostic factors that may additionally predict the TERT promoter mutation doable of these lesions and new prevention techniques in PTCs. A total of 2,539 PTC patients with 11.50% TERT mutation have been analyzed using Revman 5.3 software in this study. The PubMed and Embase databases were systematically searched for works published until November 9, 2021. The following variables had been associated with an extended chance of TERT promoter mutation in PTC patients: age < 45 years (MD = 10.93, 95%CI = 7.25-14.61); gender = male (pooled OR = 1.63, 95%CI = 1.17-2.28); tumor size > 1 cm (MD = 0.56, 95%CI = 0.34-0.77); lymph node metastasis (pooled OR = 1.29, 95%CI = 0.93-1.79); vascular invasion (pooled OR = 1.78, 95%CI = 0.83-3.84); extrathyroidal extension (pooled OR = 2.00, 95%CI = 1.32-3.02); distant metastasis (pooled OR = 1.46, 95%CI = 1.04-2.04); advanced TNM stage (pooled OR = 3.19, 95%CI = 2.28-4.45). In addition, multifocality (pooled OR = 0.67, 95%CI = 0.14-3.24) had no affiliation with TERT promoter mutation in PTC patients. Our finding showed that age < 45 years, male, tumor size > 1 cm, lymph node metastasis, vascular invasion, and superior/advanced TNM stage were dangerous elements for TERT promoter mutation of worse effect in PTCs while that multifocality was once negatively correlated. TERT promoter mutation is drastically associated with recurrence and PTC-related mortality.

Clinical features of multifocal papillary thyroid carcinoma and risk factors of cervical metastatic lymph nodes

OBJECTIVE

To analyze the clinical features of multifocal papillary thyroid carcinoma (PTC) and the risk factors of cervical metastatic lymph nodes.

METHODS

A total of 1524 patients with papillary thyroid carcinoma admitted in Gansu Provincial Cancer Hospital from January 2020 to August 2021 were enrolled, including 492 cases of multifocal PTC and 1032 cases of unifocal PTC. The clinicopathologic features of multifocal PTC and unifocal PTC were analyzed by comparing their differences in gender, ethnicity, age, body mass index, accompanying diabetes mellitus, accompanying hypertension, preoperative thyroid stimulating hormone and thyroglobulin levels, location of lesions, maximum diameter of lesions, sum of lesion diameters, central metastatic lymph nodes, lateral cervical metastatic lymph nodes, presence of Hashimoto's thyroiditis, and thyroid capsule invasion. Patients were also assessed according to the presence or absence of central metastatic lymph nodes and lateral cervical metastatic lymph nodes to understand clinicopathological parameter differences, and multivariate logistic regression analysis was used to explore the risk factors.

RESULTS

Compared with unifocal PTC group, multifocal PTC group had significantly higher proportion of patients aged over 55 years, accompanying hypertension, central metastatic lymph nodes or cervical metastatic lymph nodes, Hashimoto's thyroiditis and capsule invasion (all P<0.05); 55.1% of patients with multifocal PTC had lesions distributed bilaterally, and the maximum diameter and diameter sum of the lesions were greater than those in unifocal PTC group (all P<0.01). Multivariate logistic regression analysis showed that male, maximum diameter of lesion more than 7 mm, capsular invasion were independent risk factors for central metastatic lymph nodes (all P<0.05); while male, maximum diameter of lesion more than 7 mm, preoperative thyroglobulin more than 55 ng/mL, and central metastatic lymph nodes were risk factors for lateral cervical metastatic lymph nodes in patients with multifocal PTC (all P<0.05).

CONCLUSION

Patients with multifocal PTC have significantly higher central and lateral cervical metastatic lymph nodes, particularly for male patients with a maximum diameter of lesion more than 7 mm, invasion of capsule, and preoperative thyroglobulin more than 55 ng/mL.

Sex Bias in Differentiated Thyroid Cancer

Differentiated thyroid cancers are more frequent in women than in men. These different frequencies may depend on differences in patient's behavior and in thyroid investigations. However, an impact on sexual hormones is likely, although this has been insufficiently elucidated. Estrogens may increase the production of mutagenic molecules in the thyroid cell and favor the proliferation and invasion of tumoral cells by regulating both the thyrocyte enzymatic machinery and the inflammatory process associated with tumor growth. On the other hand, the worse prognosis of thyroid cancer associated with the male gender is poorly explained.

Significance of RAS Mutations in Thyroid Benign Nodules and Non-Medullary Thyroid Cancer

Simple Summary

Only about 4% of thyroid nodules are carcinomas and require surgery. Fine-needle aspiration cytology is the most accurate tool to distinguish benign from malignant thyroid nodules, however it yields an indeterminate result in about 30% of the cases, posing diagnostic and prognostic dilemmas. Testing for genetic mutations, including those of RAS, has been proposed for indeterminate cytology to solve these dilemmas and support the clinician decision making process. A passionate debate is ongoing on the biological and clinical significance of RAS mutations, calling into question the utility of RAS as tumor marker. Recently, the description of a new entity of non-invasive follicular thyroid neoplasm and the accurate review of more recent analyses demonstrate that RAS mutations have limited utility in both the diagnostic and prognostic setting of thyroid nodular disease.

Abstract

Thyroid nodules are detected in up to 60% of people by ultrasound examination. Most of them are benign nodules requiring only follow up, while about 4% are carcinomas and require surgery. Malignant nodules can be diagnosed by the fine-needle aspiration cytology (FNAC), which however yields an indeterminate result in about 30% of the cases. Testing for RAS mutations has been proposed to refine indeterminate cytology. However, the new entity of non-invasive follicular thyroid neoplasm, considered as having a benign evolution and frequently carrying RAS mutations, is expected to lower the specificity of this mutation. The aggressive behavior of thyroid cancer with RAS mutations, initially reported, has been overturned by the recent finding of the cooperative role of TERT mutations. Although some animal models support the carcinogenic role of RAS mutations in the thyroid, evidence that adenomas harboring these mutations evolve in carcinomas is lacking. Their poor specificity and sensitivity make the clinical impact of RAS mutations on the management of thyroid nodules with indeterminate cytology unsatisfactory. Evidence suggests that RAS mutation-positive benign nodules demand a conservative treatment. To have a clinical impact, RAS mutations in thyroid malignancies need not to be considered alone but rather together with other genetic abnormalities in a more general context.

How limited molecular testing can also offer diagnostic and prognostic evaluation of thyroid nodules processed with liquid-based cytology: Role of TERT promoter and BRAF V600E mutation analysis

BACKGROUND

Mutational analysis contributes to the diagnosis and prognosis of thyroid nodules analyzed with fine-needle aspiration cytology (FNAC). Although several advanced molecular tests based on multiple molecular markers are available for clinical use and have increased their impact on clinical management of patients, they are not widely available. Among them is BRAF V600E, one of the most studied mutations. Other genetic alterations, such as TERT promoter mutations, may coexist in thyroid carcinomas. Previous studies have demonstrated that this duet might be involved in the aggressiveness of thyroid cancer, although its prognostic value related to mortality remains undefined. The detection of such genetic alterations in thyroid liquid-based cytology (LBC) thus may assist with patient management.

METHODS

From January 2013 to June 2014, 356 thyroid FNAC samples were processed by LBC, including 174 surgical follow-up samples. BRAF V600E and TERT mutation analyses were performed on both LBC and histopathology.

RESULTS

The study included 119 samples categorized as atypia of undetermined significance, 42 categorized as follicular neoplasms, 61 categorized as suspicious for malignancy, and 34 categorized as positive for malignancy. BRAF V600E mutation was detected in 10.4% of all cases, whereas TERT promoter mutations were identified in 1.1%. TERT-mutated cases belonged to the positive for malignancy category, with a histologic diagnosis of tall cell variant of papillary thyroid carcinoma. These genetic alterations correlated with lymph node metastases (P = .0349) and higher disease stage.

CONCLUSIONS

BRAF V600E and TERT analysis can be performed on LBC. TERT mutations are rarely identified in well differentiated thyroid carcinoma but are associated with higher stage. Although a larger molecular panel may offer more information, analyzing these few point mutations is still likely to be useful for managing potentially more aggressive thyroid carcinomas.

Genetic Determinants for Prediction of Outcome of Patients with Papillary Thyroid Carcinoma

Papillary thyroid carcinoma (PTC) usually presents an excellent prognosis, but some patients present with aggressive metastatic disease. BRAF, RAS, and TERT promoter (TERTp) genes are altered in PTC, and their impact on patient outcomes remains controversial. We aimed to determine the role of genetic alterations in PTC patient outcomes (recurrent/persistent disease, structural disease, and disease-specific mortality (DSM)). The series included 241 PTC patients submitted to surgery, between 2002-2015, in a single hospital. DNA was extracted from tissue samples of 287 lesions (primary tumors and metastases). Molecular alterations were detected by Sanger sequencing. Primary tumors presented 143 BRAF, 16 TERTp, and 13 RAS mutations. Isolated TERTpmut showed increased risk of structural disease (HR = 7.0, p < 0.001) and DSM (HR = 10.1, p = 0.001). Combined genotypes, BRAFwt/TERTpmut (HR = 6.8, p = 0.003), BRAFmut/TERTpmut (HR = 3.2, p = 0.056) and BRAFmut/TERTpwt (HR = 2.2, p = 0.023) showed increased risk of recurrent/persistent disease. Patients with tumors BRAFwt/TERTpmut (HR = 24.2, p < 0.001) and BRAFmut/TERTpmut (HR = 11.5, p = 0.002) showed increased risk of structural disease. DSM was significantly increased in patients with TERTpmut regardless of BRAF status (BRAFmut/TERTpmut, log-rank p < 0.001; BRAFwt/TERTpmut, log-rank p < 0.001). Our results indicate that molecular markers may have a role in predicting PTC patients' outcome. BRAFmut/TERTpwt tumors were prone to associate with local aggressiveness (recurrent/persistent disease), whereas TERTpmut tumors were predisposed to recurrent structural disease and DSM.

Characterization of Allele-Specific Regulation of Telomerase Reverse Transcriptase in Promoter Mutant Thyroid Cancer Cell Lines

Background: Telomerase reverse transcriptase (TERT) promoter mutations play a role in carcinogenesis and are found in both tumors and cancer cell lines. TERT promoter methylation, transcription factor binding, chromatin remodeling, and alternative splicing are also known to play an integral role in TERT regulation. Methods: Using nanopore Cas9 targeted sequencing, we characterized allele-specific methylation in thyroid cancer cell lines heterozygous for the TERT promoter mutation. Furthermore, using chromatin immunoprecipitation followed by Sanger sequencing, we probed allele-specific binding of the transcription factors GABPA (GA binding protein transcription factor subunit alpha) and MYC, as well as the chromatin marks H3K4me3 and H3K27me3. Finally, using coding single nucleotide polymorphisms and the long-read sequencing, we examined complementary DNA for monoallelic expression (MAE). Results: We found the mutant TERT promoter allele to be significantly less methylated than wild type, while more methylated in the gene body in heterozygous TERT mutant cell lines. We demonstrated that the transcriptional activators GABPA and MYC bind only to the mutant TERT allele. In addition, the activating and repressive chromatin marks H3K4me3 and H3K27me3, respectively, bind mutant and wild-type alleles exclusively. Finally, in heterozygous mutant cell lines, TERT exhibits MAE from the mutant allele only. Conclusions: In summary, by employing new long-read sequencing methods, we were able to definitively demonstrate allele-specific DNA methylation, histone modifications, transcription factor binding, and the resulting monoallelic transcription in cell lines with heterozygous TERT mutations.

Hot Spot TERT Promoter Mutations Are Rare in Sporadic Pancreatic Neuroendocrine Neoplasms and Associated with Telomere Length and Epigenetic Expression Patterns

Cancer cells activate a telomere maintenance mechanism like telomerase in order to proliferate indefinitely. Telomerase can be reactivated by gain-of-function Telomerase Reverse Transcriptase (TERT) promoter mutations (TPMs) that occur in several cancer subtypes with high incidence and association with diagnosis, prognosis and epigenetics. However, such information about TPMs in sporadic pancreatic neuroendocrine neoplasms (pNENs) including tumor (pNET) and carcinoma (pNEC) is less well defined. We have studied two hot spot TPMs and telomere length (TL) in pNEN and compared the results with clinicopathological information and proliferation-associated miRNA/HDAC expression profiles. DNA was isolated from formalin-fixed paraffin-embedded (FFPE) tissue of 58 sporadic pNEN patients. T allele frequency of C250T and C228T TPM was analyzed by pyrosequencing, relative TL as telomeric content by qPCR. In total, five pNEN cases (9%) including four pNETs and one pNEC were identified with TPMs, four cases with exclusive C250T as predominant TPM and one case with both C250T and C228T. T allele frequencies of DNA isolated from adjacent high tumor cell content FFPE tissue varied considerably, which may indicate TPM tumor heterogeneity. Overall and disease-free survival was not associated with TPM versus wild-type pNEN cases. Binary category analyses indicated a marginally significant relationship between TPM status and longer telomeres (p = 0.086), and changes in expression of miR449a (p = 0.157), HDAC4 (p = 0.146) and HDAC9 (p = 0.149). Future studies with larger patient cohorts are needed to assess the true clinical value of these rare mutations in pNEN.

Development and Validation of a Risk Scoring System Derived from Meta-Analyses of Papillary Thyroid Cancer

BACKGROUND

The aim of this study was to develop a scoring system to stratify the risk of papillary thyroid cancer (PTC) and to select the proper management.

METHODS

We performed a systematic search of MEDLINE and Embase. Data regarding patients' prognoses were obtained from the included studies. Odds ratios (ORs) with statistical significance were extracted from the publications. To generate a risk scoring system (RSS), ORs were summed (RSS1), and summed after natural-logarithmic transformation (RSS2). RSS1 and RSS2 were compared to the eighth edition of the American Joint Committee on Cancer (AJCC) staging system and the 2015 American Thyroid Association (ATA) guidelines for thyroid nodules and differentiated thyroid carcinoma.

RESULTS

Five meta-analyses were eligible for inclusion in the study. Eight variables (sex, tumour size, extrathyroidal extension, BRAF mutation, TERT mutation, histologic subtype, lymph node metastasis, and distant metastasis) were included. RSS1 was the best of the analysed models.

CONCLUSION

We developed and validated a new RSS derived from previous meta-analyses for patients with PTC. This RSS seems to be superior to previously published systems.

Suspicious ultrasound and clinicopathological features of papillary thyroid carcinoma predict the status of TERT promoter

PURPOSE

To investigate the value of ultrasound (US) and clinicopathological features of papillary thyroid cancer (PTC) in predicting Telomerase Reverse Transcriptase (TERT) promoter mutations.

METHODS

Preoperative US images of 351 surgically confirmed PTCs were evaluated in terms of PTCs size and US features. The basic clinicopathological features were also retrieved. Univariate and multivariate analyses were performed to identify the risk factors for TERT promoter mutations. A scoring system was developed based on the cumulative number of risk factors. The area under the receiver operating characteristic curve (AUC) and cut-off value were calculated to evaluate the diagnostic performance of the scoring system for predicting TERT promoter mutations.

RESULTS

TERT promoter mutations were found in 4.84% (17/351) of patients with PTCs. Patient age >50 years (OR: 6.244, P = 0.006), multifocality (OR: 21.071, P = 0.022), taller-than-wide shape (OR: 4.934, P = 0.029), microlobulated margin (OR: 4786, P = 0.032), and capsule contact or involvement (OR: 4.668, P = 0.030) were independent risk factors for TERT promoter mutations. TERT promoter mutations were relevant to more suspicious US and clinicopathological features than TERT promoter wild-type PTC (median, 4 vs. 1, P < 0.001). The cut-off value was 2.5 and the associated AUC was 0.908 (P < 0.001).

CONCLUSIONS

The probability of TERT promoter mutations increases along with the suspicious US features and clinicopathological characteristics, which may help to recognize patients who deserve a different approach, in terms of management and follow-up, in view of the worst outcome associated to this mutation.

Radiomics in predicting mutation status for thyroid cancer: A preliminary study using radiomics features for predicting BRAFV600E mutations in papillary thyroid carcinoma

Purpose

To evaluate whether if ultrasonography (US)-based radiomics enables prediction of the presence of BRAF^V600E mutations among patients diagnosed as papillary thyroid carcninoma (PTC).

Methods

From December 2015 to May 2017, 527 patients who had been treated surgically for PTC were included (training: 387, validation: 140). All patients had BRAF^V600E mutation analysis performed on surgical specimen. Feature extraction was performed using preoperative US images of the 527 patients (mean size of PTC: 16.4mm±7.9, range, 10–85 mm). A Radiomics Score was generated by using the least absolute shrinkage and selection operator (LASSO) regression model. Univariable/multivariable logistic regression analysis was performed to evaluate the factors including Radiomics Score in predicting BRAF^V600E mutation. Subgroup analysis including conventional PTC <20-mm (n = 389) was performed (training: 280, validation: 109).

Results

Of the 527 patients diagnosed with PTC, 428 (81.2%) were positive and 99 (18.8%) were negative for BRAF^V600E mutation. In both total 527 cancers and 389 conventional PTC<20-mm, Radiomics Score was the single factor showing significant association to the presence of BRAF^V600E mutation on multivariable analysis (all P<0.05). C-statistics for the validation set in the total cancers and the conventional PTCs<20-mm were lower than that of the training set: 0.629 (95% CI: 0.516–0.742) to 0.718 (95% CI: 0.650–0.786), and 0.567 (95% CI: 0.434–0.699) to 0.729 (95% CI: 0.632–0.826), respectively.

Conclusion

Radiomics features extracted from US has limited value as a non-invasive biomarker for predicting the presence of BRAF^V600E mutation status of PTC regardless of size.

Association between TERT promoter mutations and clinical behaviors in differentiated thyroid carcinoma: a systematic review and meta-analysis

BACKGROUND

The association between telomerase reverse transcriptase (TERT) promoter mutations and some clinical behaviors in thyroid cancer remains controversial and requires additional investigation. This study aimed to evaluate the association between TERT promoter mutations and clinical behaviors (including clinicopathological features and prognosis) in differentiated thyroid carcinomas (DTC).

METHODS

We performed an up-to-date systematic review and current comprehensive meta-analysis. We searched three electronic databases for relevant studies. We used fixed- or random-effect models to calculate pooled estimated odds ratios (ORs) or standardized mean differences (SMDs) and corresponding 95% confidence intervals (CIs).

RESULTS

We included 51 eligible studies incorporating 11,382 cases. Average frequencies of TERT promoter mutations in DTC, papillary (PTC), and follicular (FTC) thyroid carcinomas were 10.9%, 10.6%, and 15.1%, respectively. In DTC and PTC, TERT promoter mutations were significantly associated with sex, age, tumor size, vascular invasion, extrathyroidal extension, lymph node and distant metastases, advanced tumor, nodes, and metastasis (TNM) stage, persistence/recurrence, and disease-specific mortality. In FTC, TERT promoter mutations were significantly associated with age, distant metastases, advanced TNM stage, persistence/recurrence, and disease-specific mortality.

CONCLUSIONS

TERT promoter mutations could be considered as biomarkers assisting in risk stratification, prognostic prediction, and individualizing therapeutic options for DTC (PTC and FTC).

Molecular Alterations in Thyroid Carcinoma

Thyroid carcinoma is the most common cancer in the endocrine system. Recent advances, using next-generation sequencing, have shed light on the molecular pathogenesis of thyroid cancer. Constitutional activation of the mitogen-activated protein kinase pathway through RAS mutation, BRAF mutation, and/or fusions involving receptor tyrosine kinase (eg, (REarranged during Transfection) RET-PTC) plays a central role in tumorigenesis and opens doors to promising tyrosine kinase inhibitor therapy. Several molecular signatures, such as TERT promoter mutation and TP53 mutation, are associated with tumor progression. This article provides a concise and updated summary of the main genetic alterations in thyroid carcinoma.

Prognostic Parameters in Differentiated Thyroid Carcinomas

Differentiated thyroid carcinomas make up most thyroid malignancies. The AJCC staging system and the ATA risk prediction system are the best predictors of mortality and recurrence, respectively. Key factors to be identified and reported by pathologists are reviewed in this article and include: (1) aggressive histologic variants of papillary thyroid carcinoma (including tall cell, columnar cell, and hobnail variants); (2) presence of gross extrathyroidal extension (into skeletal muscle or adjacent organs); (3) angioinvasion (including number of foci); (4) number, anatomic level, and size of lymph node metastases; (4) extranodal extension; (5) genetics (especially BRAF V600E or TERT promoter mutation).

Risk Stratification in Differentiated Thyroid Cancer: From Detection to Final Follow-Up

CONTEXT

Modern management of differentiated thyroid cancer requires individualized care plans that tailor the intensity of therapy and follow-up to the estimated risks of recurrence and disease-specific mortality.

DESIGN

This summary is based on the authors' knowledge and extensive clinical experience, supplemented by review of published review articles, thyroid cancer management guidelines, published staging systems, and original articles identified through a PubMed search, which included terms such as risk stratification, staging, clinical outcomes, and differentiated thyroid cancer.

MAIN OUTCOME MEASURES

In the past, risk stratification in differentiated thyroid cancer usually referred to a static estimate of disease-specific mortality that was based on a small set of clinicopathological features available within a few weeks of completing initial therapy (thyroidectomy, with or without radioactive iodine). Today, risk stratification is a dynamic, active process used to predict the appropriateness for minimalistic initial therapy, disease-specific mortality, risk of recurrence, and the most likely response to initial therapy. Rather than being a static prediction available only after initial therapy, modern risk stratification is a dynamic, iterative process that begins as soon as a suspicious nodule is detected and continues through final follow-up.

CONCLUSIONS

Dynamic risk assessment should be used to guide all aspects of thyroid cancer management, beginning before a definitive diagnosis is made and continuing through the final follow-up visit.

Integrative analysis of genomic and transcriptomic characteristics associated with progression of aggressive thyroid cancer

Anaplastic thyroid cancer (ATC) and advanced differentiated thyroid cancers (DTCs) show fatal outcomes, unlike DTCs. Here, we demonstrate mutational landscape of 27 ATCs and 86 advanced DTCs by massively-parallel DNA sequencing, and transcriptome of 13 ATCs and 12 advanced DTCs were profiled by RNA sequencing. TERT, AKT1, PIK3CA, and EIF1AX were frequently co-mutated with driver genes (BRAF^V600E and RAS) in advanced DTCs as well as ATC, but tumor suppressors (e.g., TP53 and CDKN2A) were predominantly altered in ATC. CDKN2A loss was significantly associated with poor disease-specific survival in patients with ATC or advanced DTCs, and up-regulation of CD274 (PD-L1) and PDCD1LG2 (PD-L2). Transcriptome analysis revealed a fourth molecular subtype of thyroid cancer (TC), ATC-like, which hardly reflects the molecular signatures in DTC. Furthermore, the activation of JAK-STAT signaling pathway could be a potential druggable target in RAS-positive ATC. Our findings provide insights for precision medicine in patients with advanced TCs.

Integrative analysis of genomic and transcriptomic characteristics associated with progression of aggressive thyroid cancer

Anaplastic thyroid cancer (ATC) and advanced differentiated thyroid cancers (DTCs) show fatal outcomes, unlike DTCs. Here, we demonstrate mutational landscape of 27 ATCs and 86 advanced DTCs by massively-parallel DNA sequencing, and transcriptome of 13 ATCs and 12 advanced DTCs were profiled by RNA sequencing. TERT, AKT1, PIK3CA, and EIF1AX were frequently co-mutated with driver genes (BRAF^V600E and RAS) in advanced DTCs as well as ATC, but tumor suppressors (e.g., TP53 and CDKN2A) were predominantly altered in ATC. CDKN2A loss was significantly associated with poor disease-specific survival in patients with ATC or advanced DTCs, and up-regulation of CD274 (PD-L1) and PDCD1LG2 (PD-L2). Transcriptome analysis revealed a fourth molecular subtype of thyroid cancer (TC), ATC-like, which hardly reflects the molecular signatures in DTC. Furthermore, the activation of JAK-STAT signaling pathway could be a potential druggable target in RAS-positive ATC. Our findings provide insights for precision medicine in patients with advanced TCs.

Anaplastic thyroid cancer (ATC) and advanced differentiated thyroid cancers (DTCs) come with a dismal prognosis. Here, Yoo and colleagues reveal the genomic and transcriptomic landscape of ATC and DTC, highlighting potential therapeutic vulnerabilities.

[Benefits of Molecular Analyses in Thyroid Carcinoma]

Benefits of Molecular Analyses in Thyroid Carcinoma Abstract. The widespread access to neck ultrasonography has led to high detection rates of thyroid nodules, whose vast majority will remain clinically silent. In daily practice it is a challenge to filter out the thyroid nodules that require medical attention. This is usually achieved by a combination of sonomorphologic criteria and fine-needle aspiration cytology. In recent years, there is a trend toward deescalation in diagnostic and therapeutic measures for thyroid nodules. Some authors even advocate active surveillance instead of surgical approaches for very low-risk thyroid carcinoma. This approach requires an accurate assessment of the malignant potential of each thyroid nodule. As recent studies have allowed better understanding of molecular pathogenesis of thyroid cancer, the mutational profile of thyroid nodules has emerged as a new tool for assessment of thyroid nodules. Its exact clinical application in daily routine remains, however, unclear.

Genomic Characterization of Differentiated Thyroid Carcinoma

Since the release of The Cancer Genome Atlas study of papillary thyroid carcinoma (PTC) in 2014, additional genomic studies of differentiated thyroid carcinoma (DTC) using massively-parallel sequencing (MPS) have been published. Recent advances in MPS technology have started to provide important insights into the molecular pathogenesis of DTC. In the genomic landscape, the most recurrently altered genes in DTC, which has a low mutational burden relative to other cancers, are BRAF, RAS, and fusion genes. Some novel driver candidates also have been identified. The frequency of these genomic alterations varies across the subtypes of DTC (classical PTC, follicular variant of PTC, and follicular thyroid carcinoma). Telomerase reverse transcriptase (TERT) promoter mutations are the alteration that makes the most important contribution to the progression of DTC. In the transcriptomic landscape, DTC can be classified according to its gene expression profile, and each subtype has a distinct mutational profile, intracellular signaling output, and clinicopathological characteristics. Herein, we review the results of genomic studies using MPS technology, and describe the types and frequencies of genomic alterations according to histological classifications of DTC and the characteristics and significance of the gene expression signatures of DTC.

Multiple Simultaneous Rare Distant Metastases as the Initial Presentation of Papillary Thyroid Carcinoma: A Case Report

Papillary thyroid carcinoma (PTC) commonly metastasizes to regional lymph nodes. However, they infrequently cause rare distant metastases (RDMs), with the exclusion of lungs and bone metastases. RDMs are seldom identified prior to a primary thyroid cancer diagnosis. Therefore, cases initially presenting with synchronously multiple RDMs from PTC are extremely infrequent. This is a rare case of a 48-year-old man with initial diaphragm, pancreatic, and liver tumors from PTC. Following resection of the tumors, an ultrasound-guided fine-needle aspiration (US-FNA) cytology of a mass in the thyroid's left lobe revealed PTC. After postoperative recovery for more than 4 months, physical examination identified an irregular large nodule in the thyroid's isthmus and left lobe, a swollen lymph node in the left neck, and a mass in the right parotid gland. Ultrasound reexamination revealed numerous hypoechoic masses as follows: one in the thyroid's isthmus and entire left lobe (7.3 × 5.9 × 5.1 cm) and multiple in the thyroid's right lobe (0.2-0.3 cm). Ultrasound examination also showed several swollen lymph nodes in the left neck, a mass in the left gluteus maximus, and several masses in both the bilateral parotid and salivary region. The US-FNA's pathological examination confirmed metastatic PTCs in the left gluteus maximus and bilaterally located in the parotid and salivary gland. 18-fluorodeoxyglucose positron-emission tomography and computed tomography scan revealed abnormal uptakes in numerous locations (e.g., the thyroid's isthmus and left lobe, bilateral parotid gland, subcutaneous tissues, etc.). The patient underwent palliative therapy, including total thyroidectomy, bilateral central neck dissection, left lateral neck dissection, and excision of the bilateral parotid and salivary gland. A whole-body scan post-therapeutic radioactive iodine ablation showed exclusive thyroid bed uptake. Subsequently, the patient underwent continuous thyroid stimulating hormone repression therapy and was treated with lenvatinib chemotherapy for ~8 months. The primary thyroid tumor, pancreatic metastasis, and cervical lymph node metastasis were both positive for BRAF ^V600E and TERT promoter (C288T) mutations. After 13 months of follow-up, the patient is currently in stable clinical conditions. In conclusion, the present case is an extremely rare occurrence of simultaneous multiple RDMs from PTC as the initial presentation.

Genetic diagnosis of a Chinese multiple endocrine neoplasia type 2A family through whole genome sequencing

Approximately 98% of patients with multiple endocrine neoplasia type 2A (MEN 2A) have an identifiable RET mutation. Prophylactic or early total thyroidectomy or pheochromocytoma/parathyroid removal in patients can be preventative or curative and has become standard management. The general strategy for RET screening on family members at risk is to sequence the most commonly affected exons and, if negative, to extend sequencing to additional exons. However, different families with MEN 2A due to the same RET mutation often have significant variability in the clinical exhibition of disease and aggressiveness of the MTC, which implies additional genetic loci exsit beyond RET coding region. Whole genome sequencing (WGS) greatly expands the breadth of screening from genes associated with a particular disease to the whole genome and, potentially, all the information that the genome contains about diseases or traits. This is presumably due to additive effect of disease modifying factors. In this study, we performed WGS on a typical Chinese MEN 2A proband and identified the pathogenic RET p.C634R mutation. We also identified several neutral variants within RET and pheochromocytoma-related genes. Moreover, we found several interesting structural variants including genetic deletions (RSPO1, OVCH2 and AP3S1, etc.) and fusion transcripts (FSIP1-BAZ2A, etc.).

Active Surveillance for Papillary Thyroid Microcarcinoma: Challenges and Prospects

Active surveillance (AS) can be considered as an alternative to immediate surgery in low-risk papillary thyroid microcarcinoma (PTMC) without clinically apparent lymph nodes, gross extrathyroidal extension (ETE), and/or distant metastasis according to American Thyroid Association. However, in the past AS has been controversial, as evidence supporting AS in the management of PTMC was scarce. The most prominent of these controversies included, the limited accuracy and utility of ultrasound (US) in the detection of ETE, malignant lymph node involvement or the advent of novel lymph node malignancy during AS, and disease progression. We summarized publications and indicated: (1) US, performer-dependent, could not accurately diagnose gross ETE or malignant lymph node involvement in PTMC. However, the combination of computed tomography and US provided more accurate diagnostic performance, especially in terms of selection sensitivity. (2) Compared to immediate surgery patients, low-risk PTMC patients had a slightly higher rate of lymph node metastases (LNM), although the overall rate for both groups remained low. (3) Recent advances in the sensitivity and specificity of imaging and incorporation of diagnostic biomarkers have significantly improved confidence in the ability to differentiate indolent vs. aggressive PTMCs. Our paper reviewed current imagings and biomarkers with initial promise to help select AS candidates more safely and effectively. These challenges and prospects are important areas for future research to promote AS in PTMC.

Genomic Hallmarks of Thyroid Neoplasia

The genomic landscape of thyroid cancers that are derived from follicular cells has been substantially elucidated through the coordinated application of high-throughput genomic technologies. Here, I review the common genetic alterations across the spectrum of thyroid neoplasia and present the resulting model of thyroid cancer initiation and progression. This model illustrates the striking correlation between tumor differentiation and overall somatic mutational burden, which also likely explains the highly variable clinical behavior and outcome of patients with thyroid cancers. These advances are yielding critical insights into thyroid cancer pathogenesis, which are being leveraged for the development of new diagnostic tools, prognostic and predictive biomarkers, and novel therapeutic approaches.

Sensitive droplet digital PCR method for detection of TERT promoter mutations in cell free DNA from patients with metastatic melanoma

BACKGROUND

Currently mainly BRAF mutant circulating tumor DNA (ctDNA) is utilized to monitor patients with melanoma. TERT promoter mutations are common in various cancers and found in up to 70% of melanomas, including half of BRAF wild-type cases. Therefore, a sensitive method for detection of TERT promoter mutations would increase the number of patients that could be monitored through ctDNA analysis.

METHODS

A droplet digital PCR (ddPCR) assay was designed for the concurrent detection of chr5:1,295,228 C>T and chr5:1,295,250 C>T TERT promoter mutations. The assay was validated using 39 melanoma cell lines and 22 matched plasma and tumor samples. In addition, plasma samples from 56 metastatic melanoma patients and 56 healthy controls were tested for TERT promoter mutations.

RESULTS

The established ddPCR assay detected TERT promoter mutations with a lower limit of detection (LOD) of 0.17%. Total concordance was demonstrated between ddPCR and Sanger sequencing in all cell lines except one, which carried a second mutation within the probe binding-site. Concordance between matched plasma and tumor tissue was 68% (15/22), with a sensitivity of 53% (95% CI, 27%-79%) and a specificity of 100% (95% CI, 59%-100%). A significantly longer PFS (p=0.028) was evident in ctDNA negative patients. Importantly, our TERT promoter mutations ddPCR assay allowed detection of ctDNA in 11 BRAF wild-type cases.

CONCLUSIONS

The TERT promoter mutation ddPCR assay offers a sensitive test for molecular analysis of melanoma tumors and ctDNA, with the potential to be applied to other cancers.

Effects of Coexistent BRAFV600E and TERT Promoter Mutations on Poor Clinical Outcomes in Papillary Thyroid Cancer: A Meta-Analysis

BACKGROUND

The presence of a telomerase reverse transcriptase (TERT) promoter mutation has been suggested as a potential prognostic marker for thyroid cancer, and a synergistic association with the BRAF^V600E mutation has been demonstrated. The aim of this study was to verify the role of this genetic duet in papillary thyroid cancer (PTC).

METHODS

Studies of the association of BRAF^V600E and TERT promoter mutations with clinicopathologic features, recurrence, or PTC-related mortality were included from PubMed and Embase databases (inception to September 2016).

RESULTS

Thirteen eligible studies incorporating 4347 patients with PTC were included, and 283 (median 8.3%) of these patients had coexistent BRAF^V600E and TERT promoter mutations. The coexistence of the two mutations was far more strongly associated with high-risk clinicopathologic features than either mutation alone was, including advanced TNM stage (vs. BRAF^V600E: odds ratio [OR] = 4.19 [confidence interval (CI) 3.07-5.71]; vs. TERT: OR = 4.66 [CI 2.67-8.13]), extrathyroidal extension (vs. BRAF^V600E: OR = 3.1 [CI 2.2-4.37]; vs. TERT: OR = 5.66 [CI 3.02-10.6]), lymph node metastasis (vs. BRAF^V600E: OR = 1.59 [CI 1.16-2.17]; vs. TERT: OR = 2.03 [CI 1.22-3.38]), and distant metastasis (vs. BRAF^V600E: OR = 11.76 [CI 5.63-24.58]). The coexistence of the mutations showed the highest risk of recurrence (coexistence vs. no mutations: hazard ratio [HR] = 6.60 [CI 3.82-11.40]; BRAF^V600E vs. no mutations: HR = 1.31 [CI 0.49-3.46]; TERT vs. no mutations: HR = 3.38 [CI 0.85-13.35]). Moreover, PTC-related mortality was significantly higher with coexistent mutations than in the presence of BRAF^V600E alone (HR = 20.07 [CI 8.37-48.09]).

CONCLUSIONS

Coexistent BRAF^V600E and TERT promoter mutations have a synergistic effect on clinical outcomes in PTC, whereas each mutation alone has a modest effect. Therefore, molecular testing of BRAF^V600E and TERT promoter mutations together is useful in assessing risk stratification of PTC.

Refining Dynamic Risk Stratification and Prognostic Groups for Differentiated Thyroid Cancer With TERT Promoter Mutations

CONTEXT

Currently, no recurrence or mortality risk systems consider molecular testing when predicting thyroid cancer outcomes.

OBJECTIVE

We developed an integrative prognostic system that incorporates telomerase reverse transcription (TERT) promoter mutations into the recently proposed risk reclassification system after initial therapy [dynamic risk stratification (DRS)] to better categorize and predict outcomes.

DESIGN

A total of 357 differentiated thyroid cancer (DTC) patients without initial distant metastasis were enrolled. Among patients with mutated TERT and wild-type, recurrence-free survival (RFS) was compared according to DRS grouping. Cox regression was used to calculate adjusted hazard ratios (AHRs) to derive AHR groups. Performance of the AHR grouping system with respect to prediction of structural recurrence and cancer-specific survival (CSS) was assessed against the current DRS system and the tumor/node/metastasis (TNM) classification.

RESULTS

Among 357 patients, there were 90 recurrences and 15 cancer-related deaths during a median of 14 years of follow-up. Patients in higher AHR groups were at higher risk of recurrence (10-year RFS for AHR 1, 2, 3, and 4: 94.9%, 82.7%, 50.2%, and 23.1%; P < 0.001) and cancer-related death (10-year CSS: 100.0%. 98.7%, 94.2%, and 76.9%; P < 0.001). The proportions of variance explained (PVEs) for the ability of AHR and DRS grouping to predict recurrence were 22.4% and 18.5%. PVEs of AHR and TNM system to predict cancer-related deaths were 11.5% and 7.4%.

CONCLUSIONS

The AHR grouping system, a simple two-dimensional prognostic system, is as effective as DRS at predicting structural recurrence and provides clinical implication for long-term CSS in patients with nonmetastatic DTC.

Primary Thyroid Carcinoma with Low-Risk Histology and Distant Metastases: Clinicopathologic and Molecular Characteristics

BACKGROUND

Distant metastases (DM) are a rare occurrence in well-differentiated thyroid carcinoma. The aim of this study was to analyze the clinical, pathologic, and molecular features of primary thyroid carcinoma with low-risk histology that develop DM.

METHODS

A detailed clinicopathologic review and targeted next-generation sequencing were performed on a cohort of well-differentiated thyroid carcinoma lacking gross extrathyroidal extension, extensive vascular invasion, or significant lymph node metastases but exhibiting DM.

RESULTS

Primary well-differentiated thyroid carcinoma with low-risk histologic features and DM was a rare occurrence, accounting for only 3% of metastatic non-anaplastic thyroid carcinoma. All 15 cases meeting the inclusion criteria harbored DM at presentation. The majority (11/15) of these tumors were follicular variant of papillary thyroid carcinoma (PTC), especially the encapsulated form (n = 8). The remaining patients harbored encapsulated Hürthle cell carcinoma (n = 2), encapsulated follicular carcinoma (n = 1), and an encapsulated papillary carcinoma classical variant (n = 1). Of the 12 encapsulated carcinomas, 10 had capsular invasion only and no vascular invasion. Ninety-two percent of the tumors exhibited extensive intra-tumoral fibrosis. Among the eight tumors that were subjected to next-generation sequencing analysis, a RAS mutation was the main driver (5/8), and TERT promoter mutation was highly prevalent (6/8). In four cases, TERT promoter mutations were associated with RAS or BRAF mutations. BRAF-mutated classical variant of papillary carcinoma also presented with DM but was less common (1/8). In 11/15 cases, the clinician was able to diagnose distant disease based on the clinical presentation. In 3/4 incidental cases that were genotyped, TERT promoter mutations were found.

CONCLUSIONS

When DM occur in primary thyroid carcinoma with low-risk histology, they are almost always found at presentation. The majority are encapsulated follicular variant of PTC with capsular invasion only. TERT promoter mutations occur at a higher rate than that seen in PTC in general and may help explain the aggressive behavior of these histologically deceptive primary carcinomas.

Association of telomerase reverse transcriptase promoter mutations with clinicopathological features and prognosis of thyroid cancer: a meta-analysis

The clinicopathological and prognostic significance of telomerase reverse transcriptase (TERT) promoter mutations have been widely investigated in thyroid cancer; however, the results are still discrepant. Systematic searches were performed in PubMed, Web of Science, Scopus, Ovid, and the Cochran Library databases for relevant articles prior to April 2016. Mutation rates were synthesized by R statistical software. The odds ratio or standardized mean difference with 95% confidence interval was pooled by Stata. A total of 22 studies with 4,907 cases were included in this meta-analysis. TERT promoter mutations tended to present in aggressive histological types including poorly differentiated thyroid cancer (33.37%), anaplastic thyroid cancer (38.69%), and tall-cell variant papillary thyroid cancer (30.23%). These promoter mutations were likely to exist in older patients and males and were well associated with larger tumor size, extrathyroidal extension, vascular invasion, lymph node metastasis, distant metastasis, advanced tumor stage, disease recurrence/persistence, and mortality. In addition, TERT promoter mutations (especially C228T) tended to coexist with BRAF^V600E mutation, which indicated more aggressive tumor behavior. Therefore, TERT promoter mutations may be promising biomarkers for early diagnosis, risk stratification, prognostic prediction, and management of thyroid cancer.

Cancer-Specific Telomerase Reverse Transcriptase (TERT) Promoter Mutations: Biological and Clinical Implications

The accumulated evidence has pointed to a key role of telomerase in carcinogenesis. As a RNA-dependent DNA polymerase, telomerase synthesizes telomeric DNA at the end of linear chromosomes, and attenuates or prevents telomere erosion associated with cell divisions. By lengthening telomeres, telomerase extends cellular life-span or even induces immortalization. Consistent with its functional activity, telomerase is silent in most human normal somatic cells while active only in germ-line, stem and other highly proliferative cells. In contrast, telomerase activation widely occurs in human cancer and the enzymatic activity is detectable in up to 90% of malignancies. Recently, hotspot point mutations in the regulatory region of the telomerase reverse transcriptase (TERT) gene, encoding the core catalytic component of telomerase, was identified as a novel mechanism to activate telomerase in cancer. This review discusses the cancer-specific TERT promoter mutations and potential biological and clinical significances.

A scoring system is an effective tool for predicting central lymph node metastasis in papillary thyroid microcarcinoma: a case-control study

Background

The purpose of this study was to evaluate the clinicopathologic and ultrasonographic (US) characteristics and establish an effective scoring system for predicting central lymph node metastasis (CLNM) in papillary thyroid microcarcinoma (PTMC).

Methods

A total of 498 patients with PTMC who underwent total thyroidectomy or lobectomy with therapeutic central lymph node dissection (CLND) were enrolled. Univariate and multivariate analyses were performed to find the independent predictors for CLNM based on clinicopathological and US characteristics. Using the standardized regression coefficient, a 10-point score system was constructed in line with these independent predictors. Then, the scoring system was evaluated for the diagnostic value in predicting CLNM.

Results

Tumor location (the lower polo), tumor size (>5 mm), extrathyroidal extension, margin (no well-defined), display of enlarged lymph node, and contact of >25 % with the adjacent capsule were independent predictors for CLNM. Verifying the scoring system, a cutoff value of 5 points was found to be the best prediction for CLNM, the sensitivity and specificity were 64.7 and 80.5 %, respectively, and the positive and negative predictive values were 77.3 and 69.0 %, respectively.

Conclusions

The points ≤ 5 could be considered as a low risk for CLNM, and the points > 5 could be identified as a high risk for CLNM. More advanced diagnostic approaches and prophylactic CLND are needed for patients with the points > 5.