The BRAF mutation is predictive of aggressive clinicopathological characteristics in papillary thyroid microcarcinoma

Papillary microcarcinoma of the thyroid gland: Evaluation of TERT and BRAFV-600E expression and their relationship with clinicopathological findings

Papillary microcarcinomas (PMCs) are papillary carcinomas ≤1 cm in size, with an increasing incidence. Although generally indolent, some cases exhibit aggressive behavior. Recently, active surveillance has been recommended to avoid surgical treatment. Identifying molecular changes that predict aggressiveness in PMCs has gained importance, but studies are limited. We aimed to demonstrate TERT expression and BRAF V600E positivity immunohistochemically in PMCs and correlate them with histomorphological features, subtypes, and clinicopathological findings. We included 95 PMC cases diagnosed between 2010 and 2019 at the Department of Pathology, Faculty of Medicine, XXX University. We investigated TERT expression using RT-PCR. We evaluated BRAF V600E mutation immunohistochemically. We evaluated the relationship between genetic, histomorphological, and clinicopathological findings. In patients with multifocality and those with a tumor size ≥0.5 cm, the frequency of lymph node metastasis was significantly higher. A positive correlation was shown between BRAF V600E positivity and lymph node metastasis, lymphovascular invasion, advanced disease stage, and classical subtype by univariate analyses. We detected TERT expression in 18 of 95 patients (7.8 %). No relationship could be detected between TERT expression alone or combined with BRAF positivity and clinicopathological features. Although TERT mutations are associated with aggressiveness in thyroid cancers, this association was absent in PMCs. The presence of TERT expression was demonstrated in some cases. However, TERT expression could not be associated with clinicopathological findings, which is consistent with the literature suggesting that TERT plays a role in advanced stages of carcinogenesis.

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.

Risk stratification of papillary thyroid cancers using multidimensional machine learning

BACKGROUND

Papillary thyroid cancer (PTC) is one of the most common endocrine malignancies with different risk levels. However, preoperative risk assessment of PTC is still a challenge in the worldwide. Here, the authors first report a Preoperative Risk Assessment Classifier for PTC (PRAC-PTC) by multidimensional features including clinical indicators, immune indices, genetic feature, and proteomics.

MATERIALS AND METHODS

The 558 patients collected from June 2013 to November 2020 were allocated to three groups: the discovery set [274 patients, 274 formalin-fixed paraffin-embedded (FFPE)], the retrospective test set (166 patients, 166 FFPE), and the prospective test set (118 patients, 118 fine-needle aspiration). Proteomic profiling was conducted by FFPE and fine-needle aspiration tissues from the patients. Preoperative clinical information and blood immunological indices were collected. The BRAFV600E mutation were detected by the amplification refractory mutation system.

RESULTS

The authors developed a machine learning model of 17 variables based on the multidimensional features of 274 PTC patients from a retrospective cohort. The PRAC-PTC achieved areas under the curve (AUC) of 0.925 in the discovery set and was validated externally by blinded analyses in a retrospective cohort of 166 PTC patients (0.787 AUC) and a prospective cohort of 118 PTC patients (0.799 AUC) from two independent clinical centres. Meanwhile, the preoperative predictive risk effectiveness of clinicians was improved with the assistance of PRAC-PTC, and the accuracies reached at 84.4% (95% CI: 82.9-84.4) and 83.5% (95% CI: 82.2-84.2) in the retrospective and prospective test sets, respectively.

CONCLUSION

This study demonstrated that the PRAC-PTC that integrating clinical data, gene mutation information, immune indices, high-throughput proteomics and machine learning technology in multicentre retrospective and prospective clinical cohorts can effectively stratify the preoperative risk of PTC and may decrease unnecessary surgery or overtreatment.

BRAFV600E Positivity-Dependent Effect of Age on Papillary Thyroid Cancer Recurrence Risk

BRAFV600E positivity is associated with increased aggressiveness of papillary thyroid cancer (PTC), and age is an important prognostic factor. However, the association between age and BRAFV600E positivity and the recurrence risk has not been investigated. This study aimed to investigate the impact of age on recurrence between patients with BRAFV600E-positive and -negative PTC. Patients with PTC who underwent initial thyroid surgery between January 2010 and December 2018 at Seoul St. Mary's Hospital (Seoul, Republic of Korea) were retrospectively reviewed. The BRAFV600E-positive (n = 1768) and BRAFV600E-negative groups (n = 428) were divided into two subgroups: younger (<35 years) and older groups (≥55 years). In the BRAFV600E-positive group, the younger group exhibited higher lymphatic and vascular invasion rates, more positive lymph nodes, higher lymph node ratios, and higher recurrence rates than the older group (5.9% vs. 2.1%). Multivariate analysis revealed that age, lymphatic invasion, and N category were significant risk factors in the BRAFV600E-positive group. In the BRAFV600E-positive group, the younger group had a higher recurrence risk than the older group (OR, 2.528; 95% confidence interval, 1.443-4.430; p = 0.001). In the BRAFV600E-negative group, age had no impact on recurrence risk. These results contribute to tailored treatment strategies and informed patient management.

Ultrasound-guided thermal ablation for papillary thyroid microcarcinoma: the devil is in the details

Thermal ablation (TA) has harvested favorable outcomes in treating low-risk papillary thyroid microcarcinoma (PTMC). Preoperative assessment, intraoperative procedures and postoperative follow-up are all closely linked with the success and safety of TA on PTMC. However, many details in these aspects have not been systematically reviewed. This review firstly described the influence of preoperative assessment, especially for the risk of lymph node metastasis (LNM), as well as the molecular testing on the selection of TA for PTMC. Besides, we also summarized the experiences in treating special PTMC cases by TA, like multifocal lesions, PTMC located in the isthmus or adjacent to the dorsal capsule. At last, we discussed the follow-up strategies, the influence of the thyroid-stimulating hormone (TSH) level on the prognosis of PTMCs, and the management for recurrent cases. In conclusion, the procedures during the entire perioperative period should be standardized to improve the outcomes of TA in treating PTMC patients.

Transoral endoscopic and robotic thyroidectomy for thyroid cancer: the mid-term oncological outcome

BACKGROUND

Traditional open thyroidectomy is the surgical standard for thyroid cancer; however, it inevitably leaves a visible scar on the neck and affects the patient's quality of life. Therefore, to avoid making a neck incision, the transoral endoscopic thyroidectomy vestibular approach (TOETVA) and transoral robotic thyroidectomy (TORT) have been developed recently, and the surgical outcomes of these techniques are as favorable as open surgery for benign disease. Additionally, positive short-term surgical outcomes have also been achieved in a few patients with thyroid cancer. However, no data on the mid-to-long-term recurrence and survival rates of transoral thyroidectomy in thyroid cancer are available. Therefore, in this study, we analyzed the surgical outcomes and mid-term oncological results of the TOETVA and TORT in patients with thyroid cancer.

METHODS

We reviewed patients who had received TOETVA or TORT between July 2017 and November 2021 and followed up on their oncological outcomes until December 2022. Perioperative surgical and mid-term oncological outcomes were analyzed.

RESULTS

The 115 patients underwent 122 operations (57 TOETVAs and 65 TORTs), including seven complete thyroidectomies for differentiated thyroid cancer (DTC), Stage I-II, including T1-T3, N0-N1a, and initial low- to high-risk groups. There was no conversion from transoral to open surgery. TORT required a longer operating time (median [interquartile range]) than TOETVA (lobectomy: 279 [250, 318] vs. 196 [173, 253] min, p < 0.001; bilateral total thyroidectomy: 375 [309, 433] vs. 279 [238, 312] min, p < 0.001); however, no difference was found between the two groups regarding perioperative complications. Complete thyroidectomy with a second transoral approach was safe. TOETVA and TORT achieved favorable oncological outcomes with 100% survival and 98.2% acceptable response (excellent and indeterminate response) during a mean 37.88 ± 12.42 months mid-term follow-up.

CONCLUSIONS

Transoral endoscopic and robotic thyroidectomy was safe and achieved favorable mid-term oncological outcomes in a selected cohort of patients with early-stage DTC.

Comprehensive analysis of clinicopathologic and sonographic features in thyroid cancer with skip lymph node metastasis: establish and assessment of a prediction nomogram

Lateral Lymph Node Metastasis (LLNM) is common in Papillary Thyroid Carcinoma (PTC) and is associated with a poor prognosis. LLNM without central lymph node metastasis as skip metastasis is not common. We aimed to investigate clinicopathologic and sonographic risk factors for skip metastasis in PTC patients, and to establish a nomogram for predicting the possibility of skip metastasis in order to determine the therapeutic strategy. We retrospectively reviewed the data of 1037 PTC patients who underwent surgery from 2016 to 2020 at a single institution. Univariate and multivariate analyses were used to identify the clinicopathologic and preoperative sonographic risk factors of skip metastasis. A nomogram including the risk factors for predicting skip metastasis was further developed and validated. The incidence of skip metastasis was 10.7%. The univariate and multivariate analyses suggested that gender (p= 0.001), tumor location (p= 0.000), extrathyroidal extension (p= 0.000), and calcification (p= 0.000) were independent risk factors. For papillary thyroid microcarcinoma, tumor location (p= 0.000) and calcification (p= 0.001) were independent risk factors. A nomogram according to the clinicopathologic and sonographic predictors was developed. The receiver operating characteristic curve indicated that AUC was 0.824 and had an excellent consistency. The calibration plot analysis showed a good performance and clinical utility of the model. Decision curve analysis revealed it was clinically useful. A nomogram for predicting the probability of skip metastasis was developed, which exhibited a favorable predictive value and consistency. For the female PTC patient, tumor located at the upper pole is more likely to have skip metastasis. Surgeons and sonographers should pay close attention to the patients who have the risk factors. Evidence level: This article's evidence level is 3. Level 3 evidence is derived from non-randomized, controlled clinical trials. In this study, patients who receive an intervention are compared to a control group. Authors may detect a statistically significant and clinically relevant outcome.

Advances in Molecular Profiling and Their Potential Influence on the Extent of Surgery in Well-Differentiated Thyroid Carcinoma (WDTC)

Thyroid cancer surgery has evolved dramatically with advances in our understanding of the biological behaviour of WDTC. Molecular profiling is shedding light on the subset that may behave aggressively. In an era when thyroid cancer management is becoming increasingly conservative, decision making regarding the extent of surgery must be objectively guided by molecular markers. The aim of the present article is to summarise the current published literature and provide possible practice recommendations. An online search for relevant published articles was performed using several databases. Title, abstract, and full-text screening, along with data extraction, was performed by two independent reviewers after the inclusion and exclusion criteria were defined. A total of 1241 articles were identified, and 82 relevant articles were extracted and scrutinised. BRAF V600E and TERT promoter mutations were found to be associated with an increased risk of disease recurrence and distant metastases. Several other mutations have been identified that enhance disease aggressiveness (such as RET/PTC, PTEN, and TP53). One of the most important determinants of the outcome in WDTC is the extent of surgical resection. The evolution of molecular testing has reached a stage of personalised incorporation into surgical practice. Guidelines for molecular testing and surgery in WDTC will need to be clearly defined, arguably representing the next chapter in the management of the disease.

Brain metastases of papillary thyroid carcinoma origin are derived from aggressive histologic variants and demonstrate similar adverse morphology in the metastatic lesion

BACKGROUND

Distant metastases of papillary thyroid carcinoma are exceedingly rare. We analyzed all cases of brain metastases of papillary thyroid cancer at our institution and performed a literature review over the past ten years to identify histologic and molecular features of primary and metastatic tumors.

METHODS

Following institutional review board approval, the entire pathology archives at our institution were searched for cases of papillary thyroid carcinoma metastatic to brain. Patient demographics, histologic features of both primary and metastatic tumors, molecular information, and clinical outcomes were investigated.

RESULTS

We identified 8 cases of metastatic papillary thyroid carcinoma to brain. The average age at time of diagnosis of metastases was 56.3 years (range: 30-85). Average time from diagnosis of primary thyroid cancer to brain metastasis was 9.3 years (range: 0-24 years). All primary thyroid carcinomas demonstrated aggressive sub-types which were correspondingly seen in brain metastases. Next-generation sequencing revealed the most common mutations were identified in BRAFV600E, NRAS, and AKT1 with one tumor harboring a TERT promoter mutation. Six out of eight patients were deceased at the time of study with an average survival time of 2.3 years (range: 0.17-7 years) following diagnosis of brain metastasis.

CONCLUSIONS

Based on our study, it is highly unlikely that a low-risk variant of papillary thyroid carcinoma will metastasize to the brain. Therefore, careful and accurate reporting of the papillary thyroid carcinoma subtype in primary thyroid tumors is warranted. Certain molecular signatures are associated with more aggressive behavior and worse patient outcomes and next-generation sequencing should be performed on metastatic lesions.

Nomogram for preoperative prediction of high-volume lymph node metastasis in the classical variant of papillary thyroid carcinoma

Introduction

The objective of our study was to construct a preoperative prediction nomogram for the classical variant of papillary thyroid carcinoma (CVPTC) patients with a solitary lesion based on demographic and ultrasonographic parameters that can quantify the individual probability of high-volume (>5) lymph node metastasis (HVLNM).

Materials and methods

In this study, a total of 626 patients with CVPTC from December 2017 to November 2022 were reviewed. Their demographic and ultrasonographic features at baseline were collected and analyzed using univariate and multivariate analyses. Significant factors after the multivariate analysis were incorporated into a nomogram for predicting HVLNM. A validation set from the last 6 months of the study period was conducted to evaluate the model performance.

Results

Male sex, tumor size >10 mm, extrathyroidal extension (ETE), and capsular contact >50% were independent risk factors for HVLNM, whereas middle and old age were significant protective factors. The area under the curve (AUC) was 0.842 in the training and 0.875 in the validation set.

Conclusions

The preoperative nomogram can help tailor the management strategy to the individual patient. Additionally, more vigilant and aggressive measures may benefit patients at risk of HVLNM.

Is There a Role for Molecular Testing for Low-Risk Differentiated Thyroid Cancer? A Cost-Effectiveness Analysis

Molecular testing for thyroid nodules has been rapidly developed in recent years, aiming to predict the presence of malignancy and aggressive features. While commonly utilized to predict malignancy, its role in guiding the management approach is still developing. The high cost of genetic tests and long-term sequences of thyroid cancer is limiting to real-life studies. Objective: To evaluate the cost effectiveness of molecular testing for low-risk differentiated thyroid cancer (lrDTC). Methods: We developed a Markovian decision tree model of a simulated lrDTC cohort, comparing two management strategies: (I) Conducting genetic tests (GT)-patients are stratified into three risk groups for distant metastasis by the identified molecular markers: low-, intermediate- and high-risk molecular profile; followed by management accordingly: patients with low-risk will undergo hemithyroidectomy (HT), patients with intermediate-risk will undergo total thyroidectomy (TT), and high-risk patients will undergo TT with central neck dissection; (II) Without genetic tests (wGT)-all patients will undergo HT according to the ATA recommendations for lrDTC. Outcomes were measured as quality-adjusted life years (QALYs) and costs of each strategy. Results: GT was found as cost effective, leading to a gain of 1.7 QALYs with an additional cost of $327 per patient compared to wGT strategy. This yielded an incremental cost-effectiveness ratio of $190 per QALY. Sensitivity analysis demonstrated robust results across the variables' ranges. The most impactful variable was the benefit from performing TT rather than HT for intermediate to high-risk patients. Conclusions: Our model found that molecular testing for lrDTC is cost-effective, allowing tailored management according to the patient's personal risk level reflected in the genetic profile, hence improving outcomes.

Association of BRAFV600E Mutation with the Aggressive Behavior of Papillary Thyroid Microcarcinoma: A Meta-Analysis of 33 Studies

An association between the BRAF^V600E mutation and the clinicopathological progression of papillary thyroid microcarcinoma (PTMC) has been suggested. We aimed to summarize the relevant literature and determine the predictive value of BRAF^V600E mutation in predicting clinical outcomes and risk stratification in patients with PTMC. A systematic search using PubMed, Cochrane, and Embase up to February 2020 was performed. A total of 33 studies met the inclusion criteria, resulting in a pool of 8838 patients, of whom 5043 (57.1%) patients were positive for BRAF^V600E mutation. Tumors with positive BRAF^V600E mutation had a higher tendency for multifocality (RR = 1.09, 95%CI = 1.03-1.16), extrathyroidal extension (RR = 1.79, 95%CI = 1.37-2.32), and lymph node metastasis (RR = 1.43, 95%CI = 1.19-1.71). Patients with BRAF^V600E mutation were at increased risk of disease recurrence (RR = 1.90, 95%CI = 1.43-2.53). PTMC in patients positive for the BRAF^V600E mutation is more aggressive than wild-type BRAF PTMC. Since BRAF-mutated PTMC is generally more resistant to radioiodine treatment, patients with BRAF^V600E-mutated PTMC may require earlier management, such as a minimally invasive ablative intervention. Conservative management by active surveillance may be suitable for patients with wild-type BRAF^V600E PTMC.

Re-do Operation Using a Robotic System due to Locoregional Recurrence after Initial Thyroidectomy for Thyroid Cancer

Locoregional recurrent thyroid cancer is commonly treated with re-do operation. This study aimed to investigate the feasibility of using robotic system for re-do operation in locoregional recurrent thyroid cancer. Sixty-five patients who underwent re-do robotic operation using trans-axillary approach for locoregional recurrent thyroid cancer from October 2007 to April 2021 at Yonsei University Hospital were analyzed. Completion total thyroidectomy (CTT) was performed in 26 cases, CTT and modified radical neck node dissection (mRND) in 16, and mRND in 23. Most of the re-do robotic operations were performed at site of previous incision. All patients were diagnosed with papillary thyroid carcinoma (PTC). CTT with central compartment neck dissection (CCND) took 117.6 ± 26.3 min, CTT with mRND 255.6 ± 38.6 min, and mRND, 211.7 ± 52.9 min. Transient hypocalcemia occurred in 17 (26.2%) patients and permanent hypocalcemia occurred in 3 (4.6%). There was one case of recurrent laryngeal nerve(RLN) injury. One patient was diagnosed with structural recurrence after re-do robotic operation. Median follow-up duration was 50.7 ± 37.1 months. Re-do robotic operation can be an alternative for patients who are diagnosed with locoregional recurrent thyroid cancer after thyroidectomy, with no increase in morbidity, similar oncologic outcomes, and superior cosmetic satisfaction.

Genotypes of Papillary Thyroid Carcinoma With High Lateral Neck Metastasis in Chinese Population

Papillary Thyroid Carcinoma (PTC) is one of the most commonly diagnosed cancer types in China, characterized by its early age at diagnosis and high 25-year survival rate. Distinct mutational patterns in PTC have been linked to activation of the mitogen-activated protein kinase (MAPK) signaling pathway. To explore the clinical significance of genomic variation patterns in Chinese patients with thyroid carcinoma, we investigated the genomic variants in 83 PTC cases with complete clinical records. The mutational patterns were evaluated using a 688-gene panel which covered known driver genes in PTC tumorigenesis, and featured genetic markers in various PTC-related pathways. We evaluated the relationship between mutational landscape and various clinical information in PTC patients with lateral lymph node metastasis. BRAF V600E was the most common mutation. Mutations in NF1, CDC27, PMS2 and PPP4R2 were more common in men, and mutations in NF1, PMS2 and TERT were related to lateral lymph node metastasis. According to the clustering of mutational patterns, we show that the underline driving mechanisms in lateral lymph node metastasis can be divided into two major groups (BRAF-TERT pathway, and NF1-PMS2 pathway). When combined with the TERT mutations, the BRAF mutation group was prone to lateral lymph node metastasis, particularly in elderly women. The NF1 mutations usually co-existed with PMS2 mutations, and this group included more men and young patients who had a high tumor mutational burden and lateral lymph node metastasis rate.

Correlation between Ultrasonographic Appearance of Papillary Thyroid Microcarcinoma and BRAF V600E Mutation

The study was conducted to investigate the correlation between the ultrasonographic appearance of a thyroid nodule and the BRAF V600E mutation. Patients with thyroid nodules (n = 186), for which BRAF V600E testing and cytopathology analysis were performed, and who underwent subsequent surgery for nodule resection were enrolled in this study. For each patient, color Doppler ultrasonography was performed to observe the variables of the nodules. The nodules were then characterized using the thyroid imaging reporting and data system classification TI-RADS. Furthermore, the ultrasonographic appearance of the control group, encompassing patients with nodular thyroid goiters, and the case group, encompassing patients with papillary thyroid microcarcinoma (PTMC), was statically analyzed. Similarly, a statistical analysis of the ultrasonographic appearance of the BRAF V600E-positive and BRAF V600E-negative subgroups was also performed. The accuracy was significantly different for the corresponding values when color Doppler ultrasonography, BRAF V600E testing, or cytopathology alone was used for diagnosis. There were significant differences in the ultrasonographic appearance variables between the control and case groups. Comparing with the BRAF V600E-negative subgroup of the case group, the ultrasonographic appearances of the BRAF V600E-positive subgroup showed less circumscribed and more irregularly shaped nodules, with significantly different aspect ratios of >1. The combination of BRAF V600E testing and color Doppler ultrasonography or cytopathology improved the accuracy of the PTMC diagnose. We found that the ultrasonographic appearance of thyroid nodules was related to PTMC.

The Diagnostic Efficacy of the American College of Radiology (ACR) Thyroid Imaging Report and Data System (TI-RADS) and the American Thyroid Association (ATA) Risk Stratification Systems for Thyroid Nodules

BACKGROUND

This study is aimed at evaluating the diagnostic efficacy of ultrasound-based risk stratification for thyroid nodules in the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) and the American Thyroid Association (ATA) risk stratification systems.

METHODS

286 patients with thyroid cancer were included in the tumor group, with 259 nontumor cases included in the nontumor group. The ACR TI-RADS and ATA risk stratification systems assessed all thyroid nodules for malignant risks. The diagnostic effect of ACR and ATA risk stratification system for thyroid nodules was evaluated by receiver operating characteristic (ROC) analysis using postoperative pathological diagnosis as the gold standard.

RESULTS

The distributions and mean scores of ACR and ATA rating risk stratification were significantly different between the tumor and nontumor groups. The lesion diameter > 1 cm subgroup had higher malignant ultrasound feature rates detected and ACR and ATA scores. A significant difference was not found in the ACR and ATA scores between patients with or without Hashimoto's disease. The area under the receiver operating curve (AUC) for the ACR TI-RADS and the ATA systems was 0.891 and 0.896, respectively. The ACR had better specificity (0.90) while the ATA system had higher sensitivity (0.92), with both scenarios having almost the same overall diagnostic accuracy (0.84).

CONCLUSION

Both the ACR TI-RADS and the ATA risk stratification systems provide a clinically feasible thyroid malignant risk classification, with high thyroid nodule malignant risk diagnostic efficacy.

Preoperative and pathological predictive factors of central lymph node metastasis in papillary thyroid microcarcinoma

OBJECTIVE

The aim of this study was to identify clinical and pathological markers of CLNM in persons with clinical lymph node-negative papillary thyroid microcarcinoma(PTMC).

MATERIALS AND METHODS

Retrospective data were analyzed from 804 PTMC clinically negative patients who were receiving thyroid surgery in the First Affiliated Hospital at Chongqing Medical University from January 2017 to December 2018. The CLNM-positive and CLNM-negative groups were categorised according to histological evidence of the central lymph node involvement, statistically, risk variables for CLNM were found.

RESULTS

324 (40.3%) individuals were diagnosed with CLNM. Sex (P=0.001), age at diagnosis (P<0.001), tumour size(P=0.029), microcaccificities presence (P=0.003), capsules discontinuity(P=0.002), multi-focality(P=0.001) and (ETE)extrathyroidal extension (P < 0.001) differed substantially from one positive CLNM group to the next. For multivariate analyses, women (odds ratio [OR] = 0.489), age [OR = 0.540] are the independent protective factors for CLNM; micro-cacification presence (OR = 1.511), discontinuity of capsules (OR= 2.056), multifocality(OR=1.486) and ETE(OR=10.613) are the independent risk factors for CLNM. Feature curves of the receiver were built and the AUC is 0.763. 32.1% percent (80 patients) of the 249 patients who did not have any of the four risk variables got CLNM. This contrasted with the incidence of CLNM in this research, which was as high as 49.1%.

CONCLUSIONS

CLNM has been connected with female sex, age - within 45 years, microcacification occurrences, capsule discontinuity, multifocality and extrathyroid expansion. The patients may benefit from the surgical decision of pCLND whether there are risk factors combined.

Detection of BRAF V600E in Fine-Needle Aspiration Samples of Thyroid Nodules by Droplet Digital PCR

BACKGROUND

BRAF exon 15 p.V600E (BRAF V600E) mutation has been established as an important molecular marker for papillary thyroid carcinoma diagnosis by ultrasound-guided fine-needle aspiration biopsy (FNAB). Sanger sequencing is the gold standard for detecting BRAF V600E mutations but fails to identify low-frequency mutations. However, droplet digital PCR (ddPCR) is a popular new method for detecting low-frequency mutations. Here, we compare the efficiency of droplet digital PCR (ddPCR) and Sanger sequencing for detection of the BRAF V600E mutation in thyroid fine-needle aspiration (FNA) samples.

METHODS

Thyroid fine-needle aspiration samples from 278 patients with 310 thyroid nodules were collected. Sanger sequencing and ddPCR were conducted to detect the BRAF V600E mutation.

RESULTS

The BRAF V600E mutation was found in 94 nodules (30.32%) by ddPCR and 40 nodules (12.90%) by Sanger sequencing in 310 FNA samples. A total of 119 nodules were confirmed PTC by postsurgical pathology. Among which the BRAF mutation was found in 80 (67.23%) nodules by ddPCR and 31 (26.05%) by Sanger sequencing. All nodules carrying the mutation detected by Sanger sequencing (SS+) were verified by ddPCR (ddPCR+). Also, all nodules with no mutation detected by ddPCR were interpreted as wild-type by Sanger sequencing (SS-). In addition. Almost all SS+/ddPCR + nodules (95.00%; 38/40) and SS-/ddPCR + nodules (100.00%; 54/54) displayed a BRAF mutation rate of >5% and <15%, respectively, indicating easy misdetection by Sanger sequencing when the mutation rate is between 5 and 15%.

CONCLUSION

ddPCR has higher sensitivity than Sanger sequencing and we propose ddPCR as a supplement to Sanger sequencing in molecular testing of BRAF using FNAB samples.

TERT Promoter Mutations Are an Independent Predictor of Distant Metastasis in Middle Eastern Papillary Thyroid Microcarcinoma

BACKGROUND

Papillary thyroid microcarcinomas (PTMCs) have been attributed to the recent increased incidence of thyroid cancer. Although indolent, a subset of PTMC could potentially develop distant metastasis (DM). This study aimed to evaluate the clinico-pathological features and molecular characteristics of PTMC and identify the risk factors for DM in PTMC patients from Middle Eastern ethnicity.

METHODS

We retrospectively analyzed 210 patients with histologically confirmed PTMC. Clinico-pathological associations for DM, BRAF mutation and TERT mutation were analyzed successfully in 184 patients. Multivariate analysis was performed using Cox proportional hazards model and logistic regression analysis.

RESULTS

Among the PTMC patients included in this cohort, DM was noted in 6.0% (11/184), whereas tumor relapse occurred in 29/184 (15.8%). Of the 11 cases with DM, lung metastasis occurred in 8 cases, bone metastasis in 2 cases and brain metastasis in 1 case. Presence of extrathyroidal extension and male sex were significantly associated with DM. Molecular analysis showed BRAF V600E mutations to be the most frequent, being detected in 45.7% (84/184). TERT promoter mutations were detected in 16 (8.7%) cases and were significantly associated with DM and shorter metastasis-free survival in multivariate analysis.

CONCLUSIONS

Our study indicates a surprisingly high frequency of TERT promoter mutation in Saudi patients with PTMC. Identifying TERT promoter mutations as an independent predictor of DM in patients with microcarcinoma could explain the inherent aggressive nature of PTMC from Middle Eastern ethnicity and magnify its role in patient risk stratification, which might help in improving therapeutic strategy for these patients.

The relationship between lipotoxicity and risk of extrathyroidal extension in papillary thyroid microcarcinoma

OBJECTIVE

To explore the relationship between triglyceride (TG) levels and aggressive pathological characteristics in papillary thyroid microcarcinoma (PTMC) patients, especially the relationship between TG, BMI, age, and extrathyroidal extension (ETE).

METHODS

A retrospective analysis of 9663 patients with PTMC in a single center from 2010 to 2017 was included in this study. Binary logistic regression was used to analyze the relationship between serum TG and aggressive pathological characteristics of PTMC in different genders. Further analyzing the risk of high TG in different ages and BMI groups.

RESULTS

Even after adjustment for confounding factors, high TG is still a risk factor for ETE in women with PTMC, but not a risk factor for men. Compared with the group with lower than 0.90 mmol/L, when the TG level is higher than 1.93 mmol/L, the risk of ETE in women increased by about 1.35-fold. The remaining two variables (BMI, age) as risk factors for ETE are analyzed. In the normal BMI group, high TG is still a risk factor for ETE. The risk of ETE in women more than 55 years old is significantly increased by 1.96-fold (1.34-fold in less than 55 years).

CONCLUSION

High TG in women is positively correlated with the risk of ETE in PTMC. PTMC with high TG in elderly women (more than 55 years) has a higher risk of ETE. TG is a potential serological index for predicting the risk of ETE in women with normal BMI.

Ultrasound-Based Radiomic Nomogram for Predicting Lateral Cervical Lymph Node Metastasis in Papillary Thyroid Carcinoma

RATIONALE AND OBJECTIVES

Accurate preoperative identification of lateral cervical lymph node metastasis (LNM) is important for decision-making and clinical management of patients with papillary thyroid carcinoma (PTC). The aim of this study was to develop an ultrasound (US)-based radiomic nomogram to preoperatively predict the lateral LNM in PTC patients.

METHODS

In this retrospective study, a total of 886 patients were enrolled and randomly divided into 2 groups. Radiomic features were extracted from the preoperative US images. A radiomic signature was constructed using the least absolute shrinkage and selection operator algorithm in the training set. Multivariate logistic regression was performed to develop the radiomic nomogram, which incorporating the radiomic signature and the selected clinical characteristics. The performance of the nomogram was assessed by its discrimination, calibration, and clinical usefulness in both the training and validation sets.

RESULTS

The radiomic signature was significantly associated with the lateral LNM in both cohorts (p< 0.001). The nomogram that consisted of radiomic signature, US-reported cervical lymph node (CLN) status, and CT-reported CLN status demonstrated good discrimination and calibration in the training and validation sets with an AUC of 0.946 and 0.914, respectively. The decision curve analysis indicated that the radiomic nomogram was worthy of clinical application.

CONCLUSION

The radiomic nomogram proposed here has good performance for noninvasively predicting the lateral LNM and might be used to facilitate clinical decision-making and potentially improve the survival outcome in selected patients.

BRAF V600E mutation in papillary thyroid carcinoma: it's relation to clinical features and oncologic outcomes in a single cancer centre experience

PURPOSE

This study focuses on the oncologic influence of BRAF V600E mutations in a cohort of Middle Eastern papillary thyroid carcinoma (PTC) patients treated at a single centre. We tested the association of BRAF V600E mutation with papillary thyroid carcinoma at King Hussein Cancer Center.

METHODS

Patients with histologically confirmed PTC who underwent surgical treatment between 2006 and 2015 were included in this study. Oncological outcomes, both short- and long-termed, were collected.

RESULTS

A total of 128 patients (68% females) were included in this study with a mean age of 38 years (±13.8). The median follow-up period was 50 months. The BRAF V600E mutation was found in 71% of patients. The tumour size for patients with a negative BRAF V600E mutation was significantly larger in comparison to patients who tested positive for the mutation (3.47 cm vs 2.31 cm, respectively, P = 0.009). The two groups showed similar disease-free survival (DFS) rates; positive = 75% (median 43 months (0-168)) compared to 78% for the negative BRAF V600E mutation (median 38 months (3-142)) (P = 0.162, HR = 0.731) Furthermore, both groups showed similar overall survival rates, positive = 94.5% (median 56 months (0-228)) compared to 94.6% for the negative BRAF V600E mutation (median 43 months (3-157)) (P = 0.941, HR = 0.940).

CONCLUSION

BRAF V600E mutation had no effect on loco-regional recurrence, distant metastasis, overall survival, or DFS. These findings may be attributed to geographic variations or reflect that BRAF V600E may only serve as an indicator of poor prognosis in high-risk group as such.

BRAFV600E mutation is associated with increased prevalence of contralateral lymph-node metastases in low and low-to-intermediate risk papillary thyroid cancer

OBJECTIVE

Papillary thyroid cancer (PTC) is the most common endocrine malignancy. Despite good prognosis being generally associated with PTC, persistent/recurrent disease can be observed in a not negligible number of patients. Accurate postoperative management can lead to a significant improvement of risk stratification/staging of PTC patients identifying those at higher risk of a more aggressive clinical course. Molecular tests were introduced at the beginning of the 2000s to improve PTC risk stratification.

METHODS

We reviewed the records of 354/1185 patients affected by low or low-to-intermediate risk unilateral-PTC. In these patients, BRAFV600E mutation was looked for and 131-radioiodine therapy was performed 3 months after thyroid surgery. A radioiodine post-therapeutic imaging was obtained in all patients.

RESULTS

BRAFV600E mutation was found in 170/354 PTC patients (female = 126). Forty-two out of 170 BRAFV600E mutation +ve patients (female = 27) had ipsilateral (n = 24) or contralateral (n = 18) loco-regional metastases at post-therapeutic imaging. Significant differences in terms of 2015 American Thyroid Association risk stratification, Hashimoto thyroiditis prevalence, tumor size, multifocality, disease staging and aggressive variant were observed between BRAFV600E mutation +ve and BRAFV600E mutation -ve patients (P ≤ 0.001;P = 0.001; P ≤ 0.001; P = 0.026; P ≤ 0.001; P ≤ 0.001). Interestingly, the prevalence of contralateral lymph-node metastases was significantly higher in BRAFV600E mutation +ve than BRAFV600E mutation -ve patients (18/42 vs. 2/22, respectively; P = 0.013).

CONCLUSION

This study suggests that BRAFV600E mutation represents a significant risk factor for developing contralateral lymph-node metastases and confirms that BRAFV600E mutation is associated with more aggressive PTC features and a higher prevalence of metastatic disease also in low or low-to-intermediate-risk PTC patients.

A comparison between unifocal papillary thyroid microcarcinoma with noninvasive follicular thyroid neoplasm with papillary-like nuclear features and other patterns: A retrospective clinicopathological study

Background

Papillary thyroid microcarcinoma (mPTC) is defined as a tumor with low malignancy potential. Different treatment protocols have been used at different centers for analyzing this tumor which has common recurrence and metastasis rates. Consequently, in 2016, the definition of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was accepted which included the lesions > cm. It is important to explain the clinical course and appropriate treatment options for mPTC and its subtypes.

Aims

In this study, we aimed to describe the clinical course of mPTC with and without NIFTP and to determine different risk groups among these subtypes.

Material and Methods

We performed microscopic reexamination of about 280 unifocal mPTCs retrieved from our archives between 2007-2018 and analyzed the results of morphological and clinical comparison among these cases that had 0-11-years of clinical follow-up.

Results

Among 280 unifocal mPTCs, 127 cases (45.4%) had classical morphology, 58 (20.7%) had NIFTP, 53 (18.9%) had infiltrative pattern, 27 (9.6%) had oncocytic pattern, 12 (4.3%) showed capsular invasion, and 3 (1.1%) showed other morphologies. Seven patients were detected with lymph node metastasis and one with distant metastasis at diagnosis. Lymph node metastasis (recurrence) was postoperatively detected in five patients. All patients with recurrence were women. Moreover, three of these patients were in their 30s and two in 70s. The median diameter of the tumor was 3 mm. Both invasive and noninvasive cases have recurred.

Conclusion

Contrary to the results of the previous studies, the results of our study did not confirm the indolent course of mPTC with NIFTP. However, metastasis was detected both at the time of diagnosis and during the postoperative period. The malignancy potential of these tumors may not be low. Therefore, more clinicopathological and molecular studies are needed to determine the biological behavior of mPTC cases with different histology.

Molecular characterisation and clinical correlation of papillary thyroid microcarcinoma

PURPOSE

Papillary thyroid microcarcinoma (mPTC) is defined as a papillary thyroid cancer sized 10 mm or less. Despite their generally indolent clinical course and good prognosis, a subset of mPTCs shows potentially aggressive behaviour.

METHODS

To search for predictors of clinical outcome of mPTCs, we retrospectively evaluated the genetic tumour profile of 100 patients (23 M/77 F, mean age ± SD 53.8 ± 13.4 years) with histologically confirmed mPTCs through analysis of BRAF, NRAS and TERT promoter mutations as well as RET/PTC translocations.

RESULTS

Mean follow-up period was 8.4 ± 3.6 years. In 55 cases, mPTC were detected incidentally after surgery. Capsular invasion, bilateralism and multifocality were found in 11/100, 17/100 and 24/100 cases, respectively, while lymph-nodes metastases were present at diagnosis in 9/100 cases. After 3.5 ± 2.0 years, tumour relapse occurred in 6/100 cases and was locoregional in five (two in the thyroid bed, three in laterocervical lymph-nodes), while lung metastasis occurred in one case. Biochemical persistence of disease was seen in 1/100 case. Mutations occurred in 55/100 cases; BRAF^V600E was the most frequently detected (49/100) and was associated with higher tumour size, bilateralism and follicular variant but not with capsular invasion. RET/PTC rearrangements were found in 2/100 cases, NRAS^Q61R in 4/100, while no mutations of TERT promoter gene were detected. Despite the observed association between BRAF^V600E mutation and unfavourable histopathological features, we found no direct association with tumour recurrence, distant metastases and mortality.

CONCLUSION

In our study, the search for the most frequent genetic alterations as prognostic markers in mPTCs would not have changed the therapeutic strategy.

Emerging BRAF Mutations in Cancer Progression and Their Possible Effects on Transcriptional Networks

Gene mutations can induce cellular alteration and malignant transformation. Development of many types of cancer is associated with mutations in the B-raf proto-oncogene (BRAF) gene. The encoded protein is a component of the mitogen-activated protein kinases/extracellular signal-regulated kinases (MAPK/ERK) signaling pathway, transmitting information from the outside to the cell nucleus. The main function of the MAPK/ERK pathway is to regulate cell growth, migration, and proliferation. The most common mutations in the BRAF gene encode the V600E mutant (class I), which causes continuous activation and signal transduction, regardless of external stimulus. Consequently, cell proliferation and invasion are enhanced in cancer patients with such mutations. The V600E mutation has been linked to melanoma, colorectal cancer, multiple myeloma, and other types of cancers. Importantly, emerging evidence has recently indicated that new types of mutations (classes II and III) also play a paramount role in the development of cancer. In this minireview, we discuss the influence of various BRAF mutations in cancer, including aberrant transcriptional gene regulation in the affected tissues.

Associations of BRAF V600E, clinical pathology and imaging factors with the recurrence rate of papillary thyroid microcarcinoma

In the present study, the recurrence rate of papillary thyroid microcarcinoma (PTMC) was assessed by analyzing postoperative follow-up data of affected patients and its associations with BRAF V600E, clinical pathology and imaging factors were explored. A total of 506 patients with PTMC were selected who underwent surgery from January 2014 to March 2016. The maximal diameter of thyroid nodules was ≤1 cm and all patients who underwent BRAF V600E testing and evaluation for lymph node metastasis. Postoperatively, each patient was regularly followed up to detect recurrence. Categorical variables were comparatively analyzed using univariate Cox linear regression analysis to screen for protective and adverse factors influencing recurrence of PTMC. A stepwise Cox proportional hazards regression model analysis was performed to explore risk factors affecting recurrence. Among the 506 patients, 477 were followed up, 29 were lost to follow-up and 26 patients experienced recurrence. The 5-year recurrent rate of PTMC was 5.45%. The univariate Cox regression analysis indicated that PTMC recurrence was influenced by BRAF V600E, sex, multifocality, capsular invasion and lateral cervical lymph node metastasis (P<0.05), but not by age, tumor location on the thyroid, size, single central lymph node metastasis, distant metastasis and operative approach (P>0.05). The significant factors associated with recurrent PTMC were subjected to stepwise multivariate Cox proportional hazards regression model analysis and the results indicated that BRAF V600E, sex, multifocality and lateral cervical lymph node metastasis were independent factors influencing recurrence in patients with PTMC, with a statistically significant difference (P<0.05). In conclusion, BRAF V600E, sex, multifocality and lateral cervical lymph node metastasis are independent risk factors for recurrent PTMC.

Association between BRAFV600E mutation and the clinicopathological features in incidental papillary thyroid microcarcinoma: A single-center study in Turkish patients

OBJECTIVE:

In this study, we evaluated the influences of BRAF^V600E mutation on clinicopathological features in incidentally found papillary thyroid microcarcinomas (PTMCs).

METHODS:

This retrospective cohort study included 72 patients with PTMC who underwent surgery from 2008 to 2012. The mean follow-up of the whole cohort was three years. DNA was isolated using QIAamp DNA formalin-fixed, paraffin-embedded (FFPE) tissue kit. BRAF gene was amplified by the polymerase chain reaction-restriction fragment length (PCR-RFL) polymorphism method with the following primers. The clinicopathologic features (age, gender, histologic subtype, tumor size, presence of tumor capsule, bilaterality, multifocality, extrathyroidal extension (ETE), thyroid capsular invasion, presence of Hashimoto’s thyroiditis, lymph node metastasis (LNM) and distant metastasis) were compared between the BRAF (+) and BRAF (-) patient groups.

RESULTS:

BRAF^V600E mutation was detected in 30 of the 72 patients (41.6%). The presence of the mutation was statistically significantly associated with classic variant (p=0.046), invasion of thyroid capsule (p=0.002) and absence of tumor capsule (p=0.003).

CONCLUSION:

Although incidental PTMCs positive for the BRAF^V600E mutation had more invasive behavior, the presence of the mutation was not associated with recurrences within three years of follow-up.

BRAF Status in Papillary Microcarcinomas of the Thyroid Gland: a Brief Review

Papillary thyroid microcarcinoma (PTMC) is defined by the World Health Organization as papillary cancer measuring 10 mm or less in diameter. Generally, PTMC shows an indolent clinical behavior with a good prognosis, although a minority of PTMC is characterized by an aggressive course. However, efforts to identify this aggressive subset of PTMC after surgery remain inconclusive. Several oncogenic pathways have been identified in thyroid cancer and have been applied translationally to improve prognosis and clinical management. In particular, the BRAFV600E mutation was found more frequently in large, aggressive, recurrent and advanced tumors. We aimed at reviewing studies on BRAFV600E mutation as a prognostic factor in PTMC.

Clinical Analysis of BRAFV600E Mutation and Its Correlation With Sonographic Image Characteristics in Papillary Thyroid Carcinoma in Chinese Coastal Areas

This study analyzed the characteristics of BRAF^V600E mutation in papillary thyroid carcinoma (PTC) in Chinese coastal areas. We intended to identify noninvasive methods to determine BRAF^V600E status in thyroid nodules prior to surgery. BRAF^V600E mutation and the sonographic characteristics of thyroid nodules were investigated in 670 PTC patients in our hospital. We aimed to determine the relationship between BRAF^V600E mutation and the clinicopathological and sonographic imaging characteristics of PTC. The mutation rate of the BRAF^V600E was 78.2%. BRAF^V600E mutation was significantly associated with central node (univariate analyses, P = .005; multivariate analyses, P < .001, odds ratio [OR] = 10.255) and lateral node metastases (univariate analyses, P = .001; multivariate analyses, P < .001, OR = 22). It was less frequent in PTC coexisting with Hashimoto's thyroiditis (univariate analyses, P = .016; multivariate analyses, P < .001, OR = .034). Nodules without blood flow had a significantly higher mutation rate of BRAF^V600E in PTC patients (univariate analyses, P = .026). BRAF^V600E mutation was significantly associated with high suspicion in the Thyroid Imaging Reporting and Data System 5 (univariate analyses, P = .004; multivariate analyses, P = .014, OR = 6.456). Our results strongly suggest that BRAF^V600E mutation plays a potential role in lymph node metastasis (central node metastasis, OR = 10.225; lateral node metastasis, OR = 22). Some sonographic imaging features might be helpful in estimating the status of BRAF^V600E preoperatively.

The contributing factors for lateral neck lymph node metastasis in papillary thyroid microcarcinoma (PTMC)

PURPOSE

Papillary thyroid microcarcinoma (PTMC) has an excellent prognosis due to its indolent features. Only few studies have assessed the clinical factors that can predict lateral neck lymph node metastasis (LLNM) in patients with PTMC. This study aimed to examine the clinicopathological factors associated with LLNM in patients with PTMC.

METHODS

We reviewed medical records of 3578 patients with PTMC that was ≤1 cm in diameter on final pathology at Yonsei University Hospital between January 2015 and December 2017. The patients were divided into two groups (metastasis group [n = 157] and no metastasis group [n = 3421]).

RESULTS

The proportion of patients with multifocality, extrathyroidal extension (ETE), and central node metastasis was significantly higher in metastasis group (p < 0.001, p < 0.001 and p < 0.001, respectively), and the mean tumor size was relatively larger in metastasis group than in no metastasis group (0.7 ± 0.2 vs. 0.6 ± 0.2 cm, p < 0.001). However, no statistically significant differences were observed in the tumors harboring BRAF mutation between the two groups (84.8% vs. 80.6%, p = 0.199). Multivariate analysis indicated that the significant risk factors of LLNM include ETE (odds ratio [OR]: 1.904, 95% confidence interval [CI]: 1.267-2.861), multifocality (OR: 2.255, 95% CI: 1.544-3.293), and central node metastasis (OR: 7.768, 95% CI: 4.869-12.395), but not BRAF mutation (OR: 0.542, 95% CI: 0.337-0.874).

CONCLUSION

Approximately 4.4% of patients with PTMC presented with LLNM at the time of diagnosis. Moreover, the significant risk factors of LLNM include central node metastasis, ETE, and multifocal disease but not BRAF mutation.

Clinicopathologic factors and preoperative ultrasonographic characteristics for predicting central lymph node metastasis in papillary thyroid microcarcinoma: a single center retrospective study

Introduction

The treatment of papillary thyroid microcarcinoma remains controversial. Central lymph node metastasis is common in papillary thyroid microcarcinoma and it is an important consideration in treatment strategy selection.

Objective

The aim of this study was to investigate clinicopathologic risk factors and thyroid nodule sonographic characteristics for central lymph node metastasis in papillary thyroid microcarcinoma.

Methods

We retrospectively reviewed the data of 599 papillary thyroid microcarcinoma patients who underwent surgery from 2005 to 2017 at a single institution. Univariate and multivariate analyses were used to identify the clinicopathologic factors and preoperative sonographic features of central lymph node metastasis. A receiver-operating characteristic, ROC curve analysis, was performed to identify the efficacy of ultrasonographic features in predicting central lymph node metastasis. A nomogram based on the risk factors was established to predict central lymph node metastasis.

Results

The incidence of central lymph node metastasis was 22.4%. The univariate and multivariate analyses suggested that gender, age, multifocality, extrathyroidal invasion, and lateral lymph node metastasis were independent risk factors for central lymph node metastasis. The univariate and multivariate analyses revealed that nodular shape, margin, and calcification were independently associated with central lymph node metastasis. The ROC curve analysis revealed that the combination of shape, margin and calcification had excellent accuracy in predicting central lymph node metastasis. The nomogram was developed based on the identified risk factors for predicting central lymph node metastasis, and the calibration plot analysis indicated the good performance and clinical utility of the nomogram.

Conclusions

Central lymph node metastasis is associated with male gender, younger age (<45 years), extrathyroidal invasion, multifocality and lateral lymph node metastasis in papillary thyroid microcarcinoma patients. The ultrasongraphic features, such as irregular shape, ill-defined margin and calcification, may improve the efficacy of predicting central lymph node metastasis. Surgeons and radiologists should pay close attention to the patients who have these risk factors. The nomogram may help guide surgical decision making in papillary thyroid microcarcinoma.

Skip Metastases in Papillary Thyroid Carcinoma - Prevalence, Predictive and Clinicopathological Factors

Background

Cervical lymph node metastases are frequently found in papillary thyroid carcinoma (PTC) and occur in a stepwise fashion. Skip metastases that omit the central compartment and spread initially in lateral neck levels are present in a certain share of patients, and their significance is poorly understood. The aim of this prospective study was to identify their possible predictors and clinicopathological factors in a group of patients with PTC with lateral lymph node (LLN) metastases.

Methods

We enrolled 68 patients with PTC with preoperatively evaluated LLN metastases who underwent total thyroidectomy with lateral lymph node dissection between 2011 and 2018. We analysed the clinicopathological features and pattern of dissemination of continuous and skip metastases.

Results

The prevalence of skip metastases was 23.5%. Compared with the continuous metastases group, the patients were older, had primary tumors that were more often situated unilaterally, and had smaller primary tumor size. Level II was less often involved, and none of the patients with skip metastases had all LNN positive (p = 0.05).

Conclusion

Skip metastases occur more frequently in older patients and display certain clinicopathological features like smaller size of the primary tumor and dissemination in less lateral neck levels. In the view of the fact that they are found rather frequently, lateral neck regions should be meticulously investigated in patients with PTC without central lymph node (CLL) metastases.

Cystic Lateral Lymph Node Metastases From Papillary Thyroid Cancer Patients

OBJECTIVES/HYPOTHESIS

Papillary thyroid carcinoma (PTC) tends to metastasize rather early to local lymph nodes (LNs). Incidences of cystic LN metastases is relatively rare compared with that of solid LN metastases. Few studies have attempted to assess the characteristics in these patients. This study aimed to compare the clinicopathologic characteristics and surgical outcomes between patients with cystic LN metastases and those with solid LN metastases.

STUDY DESIGN

Retrospective cohort study.

METHODS

We retrospectively reviewed the data of 1,028 patients with N1b PTC who underwent bilateral total thyroidectomy with central compartment neck dissection and modified radical neck dissection between January 2005 and September 2011. Of these, 136 (13.2%) had cystic LN metastases and 892 (86.8%) had solid LN metastases. Clinicopathologic characteristics and surgical outcomes were compared between these two patient groups.

RESULTS

The proportion of patients with thyroid tumor multifocality was relatively higher in the cystic node cohort (19.9% vs. 12.7%, P = .048). The number of total metastatic LNs and positive lateral LNs was slightly higher in the cystic node cohort (11.3 ± 8.9 vs. 9.7 ± 7.5, P = .029 and 6.9 ± 6.3 vs. 5.5 ± 4.6, P = .018, respectively). The proportion of patients with recurrence was higher in the cystic node cohort (14.0% vs. 3.0%, P < .001). Multivariate analysis indicated that cystic nodes were a significant risk factor for recurrence (hazard ratio: 5.265, 95% confidence interval: 2.898-9.563).

CONCLUSIONS

This study demonstrates that cystic lateral LN metastases are associated with aggressive tumor behavior in PTC patients. and that their presence is a significant independent prognostic factor for disease-free survival.

LEVEL OF EVIDENCE

2b Laryngoscope, 2020.

Clinical and Ultrasonic Risk Factors for Lateral Lymph Node Metastasis in Papillary Thyroid Microcarcinoma: A Systematic Review and Meta-Analysis

Background: Clinical and ultrasonic risk factors for lateral lymph node metastasis (LLNM) in papillary thyroid microcarcinoma (PTMC) are not well-defined. Herein, a systematic review and meta-analysis was conducted to investigate clinicopathologic and ultrasonic risk features for LLNM in PTMC.

Methods: A systematic search of electronic databases (PubMed, Embase, Cochrane Library, and Web of Science) for studies published until April 2019 was performed. Case–control studies and randomized controlled trials that studied clinical and ultrasonic risk factors of LLNM in PTMC were included.

Results: Fourteen studies (all retrospective studies) involving 43,750 patients met final inclusion criteria. From the pooled analyses, younger age<45 (OR, 1.55; 95% CI, 1.16–2.07; P = 0.003), male patients (OR, 1.94; 95% CI, 1.55–2.42; P < 0.00), extrathyroidal extension (OR, 3.63; 95% CI, 2.28–5.77; P <0.00), tumor multifocality (OR, 2.24; 95% CI, 1.53–3.28; P <0.00), tumor > 0.5 cm (OR, 2.24; 95% CI, 1.53–3.28; P < 0.00), central lymph node metastasis (OR, 5.61; 95% CI, 4.64–6.79; P < 0.00), >25% tumor contact with thyroid capsule (OR, 6.66; 95% CI, 1.96–22.65; P = 0.002), tumor calcification (OR, 2.90; 95% CI, 1.71–4.93; P < 0.00), upper tumor (OR, 3.18; 95% CI, 2.23–4.55; P < 0.00) were significantly associated with increased risk of LLNM in PTMC, while Hashimoto's thyroiditis and other ultrasonic features (solid tumor, hypoechoic tumor, smooth margin, and taller than wide tumor) were not significantly associated with LLNM in PTMC.

Conclusions: Our analysis identified several clinicopathologic and ultrasonic factors associated with LLNM in PTMC. This finding highlights the need for a cautious and frequent postoperative surveillance of the lateral neck in high-risk PTMC patients. Moreover, high-risk ultrasonic features also need to be considered during selection of PTMC for active surveillance.

Association of BRAFV600E mutation with ultrasonographic features and clinicopathologic characteristics of papillary thyroid microcarcinoma: A retrospective study of 116 cases

OBJECTIVE

To analyze the association of BRAFV600E mutation with ultrasonographic (US) features and clinicopathologic characteristics in Chinese patients with papillary thyroid microcarcinoma (PTMC).

METHODS AND MATERIALS

We retrospectively reviewed 116 consecutive Chinese patients with PTMC diagnosed by postoperative pathology. The incidence of the BRAFV600E mutation was calculated. The US features and clinicopathologic characteristics were compared between BRAF-positive and BRAF-negative patients.

RESULTS

The BRAFV600E mutation was detected in 60.3% of patients (70 of 116). Multifocality (OR: 3.681, P = 0.031), non-parallel orientation (OR: 3.181, P = 0.041) and lymph node metastasis (OR: 4.615, P = 0.009) were significantly associated with BRAFV600E mutation. Other US and clinicopathologic characteristics were not significantly related to the presence of BRAF mutation.

CONCLUSION

Multifocality, non-parallel orientation and cervical lymph node metastasis are risk factors for BRAFV600E mutation in PTMC. These factors potentially guide treatment planning or prognosis evaluation.

Wolf in Sheep's Clothing: Papillary Thyroid Microcarcinoma in the US

BACKGROUND

The presumptive overdiagnosis of papillary thyroid microcarcinoma (PTMC) has led to an emerging trend of less-extensive operation and an inclination toward active surveillance when possible. In this study, we aimed to examine the risk of advanced PTMC at presentation.

STUDY DESIGN

We conducted a retrospective analysis using the National Cancer Database (2010 to 2014). Patients with PTMC who underwent surgical intervention were included and patients with a history of any cancer were excluded.

RESULTS

A total of 30,180 adult patients with PTMC were identified; 5,628 patients (18.7%) presented with advanced features, including central lymph node (LN) metastasis (8.0%), lateral LN metastasis (4.4%), microscopic extrathyroidal extension (ETE; 6.7%), gross ETE (0.3%), lymphovascular invasion (LVI; 4.4%), and distant metastasis (0.4%). All of those features were associated with a significantly lower survival rate (p < 0.05 each) except for microscopic ETE and LVI. There was a significant interrelation among those features, distant metastasis was associated with central LN metastasis (odds ratio [OR] 2.44; 95% CI, 1.48 to 4.23; p < 0.001), lateral LN metastasis (OR 3.18; 95% CI, 1.77 to 5.71; p < 0.001), and gross ETE (OR 9.91; 95% Cl, 3.83 to 25.64; p < 0.001). In turn, nodal metastasis was associated with microscopic ETE (OR 4.23; 95% CI, 3.82 to 4.70; p < 0.001) and LVI (OR 7.17; 95% CI, 6.36 to 8.08; p < 0.001).

CONCLUSIONS

PTMC could exhibit advanced features in 19% of patients who underwent operation and some of those, such as LVI and microscopic ETE, are undetectable with preoperative workup. Clinicians need to be cognizant of this considerable risk in the era of less-aggressive management of PTMC.

Does the Site of Origin of the Microcarcinoma with Respect to the Thyroid Surface Matter? A Multicenter Pathologic and Clinical Study for Risk Stratification

It is unclear whether the site of origin of papillary thyroid microcarcinoma (mPTC) with respect to the thyroid surface has an influence on clinicopathologic parameters. The objectives of the study were to: (i) Accurately measure the mPTC distance from the thyroid surface; (ii) analyze whether this distance correlates with relevant clinicopathologic parameters; and (iii) investigate the impact of the site of origin of the mPTC on risk stratification. Clinicopathologic features and BRAF mutational status were analyzed and correlated with the site of origin of the mPTC in a multicenter cohort of 298 mPTCs from six Italian medical institutions. Tumors arise at a median distance of 3.5 mm below the surface of the thyroid gland. Statistical analysis identified four distinct clusters. Group A, mPTC: size ≥ 5 mm and distance of the edge of the tumor from the thyroid capsule = 0 mm; group B, mPTC: size ≥ 5 mm and distance of the edge of the tumor from the thyroid capsule > 0 mm; group C, mPTC: size < 5 mm and distance of the edge of the tumor from the thyroid capsule = 0 mm; and group D, mPTC: size < 5 mm and distance of the edge of the tumor from the thyroid capsule > 0 mm. Univariate analysis demonstrates significant differences between the groups: Group A shows the most aggressive features, and group D the most indolent ones. By multivariate analysis, group A tumors are characterized by tall cell histotype, BRAF V600E mutation, tumor fibrosis, aggressive growth with invasive features, vascular invasion, lymph node metastases, and intermediate ATA risk. The mPTC clinicopathologic features vary according to the tumor size and distance from the thyroid surface. A four-group model may be useful for risk stratification and to refine the selection of nodules to be targeted for fine needle aspiration.

A meta-analysis evaluating the relationship between B-type Raf kinase mutation and cervical lymphatic metastasis in papillary thyroid cancer

BACKGROUND

B-type Raf kinase (BRAF) mutation is proved to be a critical predictive factor in papillary thyroid cancer (PTC) with aggressive characteristics. However, the association between BRAF mutation and cervical lymphatic metastasis in PTC is controversial.

METHODS

We searched papers on the study of BRAF mutation and cervical lymphatic metastasis in PTC patients through PubMed, Web of Science, Embase, and Cochranelibrary. The BRAF (+) cases, BRAF (-) cases, and cervical lymphphatic metastatic cases in both BRAF (+) and BRAF (-) groups were collected. After Quality assessment, statistical Analysis (funnel plot and Harbord evaluation, Random-effect model, heterogeneity, subgroup analysis, sensitivity analysis, and metacum analysis) were done by the Review Manager (RevMan) 5.3 and stata14 statistical software.

RESULTS

There were 78 cross-section studies which met our inclusion criteria. And all of them had no selection bias, publication bias, or any other bias. A significant association existed between BRAF mutation and cervical lymph node metastasis (LNM) (odds ratio [OR] = 1.63; 95% confidence interval [CI]: 1.44-1.84; P < .05). Overall, 46 studies were conducted among East Asians. Twenty four articles had provided the data of central lymph node metastasis (CLNM), 11 articles with the data of lateral lymph node metastasis (LLNM), and classic/conventional PTC (CPTC) was analyzed in 10 studies. Subgroup analyses were performed based on ethnicity, metastatic site, and subtype of PTC. Significant association between BRAF (+) mutation and cervical LNM were indicated in East Asians (OR = 1.73; 95% CI: 1.49-2.02; P < .05), in non-East Asians (OR = 1.57; 95% CI: 1.26-1.96; P < .05), and in CLNM (OR = 1.80; 95% CI: 1.56-2.07; P < .05). While no significant association was found in LLNM (OR = 1.37; 95% CI: 0.76-2.48; P = .29 > .05) and in CPTC (OR = 1.32; 95% CI: 0.97-1.80; P = .08 > .05). We did not find any other major changes when sensitivity analysis was performed. The metacum analysis showed no significant association existed before 2012. While a significant association began to exist between BRAF mutation and LNM from 2012, and this association became stable from 2017.

CONCLUSIONS

We consider that a significant association exists between BRAF mutation and cervical LNM. Further meta-analysis on subgroup may reveal some valuable factors between BRAF gene mutation and LNM. And we do not recommend that BRAF (+) as the biomarker for LNM in PTC.

Total thyroidectomy versus thyroid lobectomy in the treatment of papillary carcinoma

Extent of thyroidectomy for papillary thyroid carcinoma is still matter of debate. Indeed, recently, international guidelines endorsed thyroid lobectomy as initial surgical approach for low risk, small medium-sized (T1-T2), N0 papillary thyroid carcinoma in absence of extrathyroidal extension. When dealing with a conservative surgery for oncologic disease is of utmost importance to exclude effectively more advanced disease, which could benefit from a more aggressive initial operation. However, in the setting of surgery for papillary thyroid carcinoma, despite an accurate preoperative work up could led to identify some suspicious characteristics as macroscopic evidence of multifocality or extrathyroidal extension, and/or evidence of lateral neck lymph node metastases, it is difficult to reliably assess the central neck nodal status both pre- and intra-operatively. Frozen section examination of the central neck nodes ipsilateral to the side of the tumor has been proposed in patients scheduled for thyroid lobectomy, in order to modulate the extension of both thyroidectomy and central neck dissection. Future molecular and genetic evidences are needed to establish high-risk patients with small papillary thyroid carcinoma in which thyroid lobectomy could be not and adequate surgical treatment.

Clinicopathological and Prognostic Significance of WW Domain Binding Protein 5 Expression in Papillary Thyroid Carcinoma

Objectives

Many patients with papillary thyroid cancer (PTC) have a high recurrence risk and poor prognosis, and the main obstacle to the clinical diagnosis and treatment of PTC is lack of effective predictive molecular markers. The purpose of this study was to investigate the clinicopathological and prognostic implications of WW domain binding protein 5 (WBP5) expression in PTC.

Materials and Methods

Immunohistochemistry of WBP5 was performed using tissue microarrays of 131 patients with PTC who underwent surgery during January 2006 and January 2010 in the Zhejiang Cancer Hospital. Statistical analyses were conducted to evaluate the association between WBP5 expression and the clinicopathological features and to analyze the disease-free survival (DFS) and prognostic factors.

Results and Conclusion

The positive expression rate of WBP5 in PTC and the adjacent normal tissues was 42.75% (56/131) and 45.45% (10/22), respectively. WBP5 expression was significantly correlated with bilaterality, capsule invasion, and N-stage, and it was a favorable factor of DFS. Moreover, patients with a high WBP5 expression exhibited reduced risk of disease recurrence compared with that in patients with low WBP5 expression in the univariate analysis, whereas the multivariate analysis suggested that WBP5 was not an independent prognostic factor. Our results indicate that WBP5 might be a favorable prognosis indicator of PTC.

Microfluidic Droplet Digital PCR Is a Powerful Tool for Detection of BRAF and TERT Mutations in Papillary Thyroid Carcinomas

We examined the utility of microfluidic digital PCR (dPCR) for detection of BRAF and TERT mutations in thyroid tumors. DNA extracted from 100 thyroid tumors (10 follicular adenomas, 10 follicular cancers, 5 medullary cancers, and 75 papillary thyroid cancer (PTC) were used for detection of BRAF and TERT mutations. Digital PCRs were performed using rare mutation SNP genotyping assays on QuantStudio 3D platform. In PTCs, BRAFV600E was detected by dPCR and Sanger sequencing in 42/75 (56%) and in 37/75 (49%), respectively. BRAFV600E was not detected in other tumors. The ratio of mutant/total BRAF alleles varied from 4.7% to 47.5%. These ratios were higher in classical PTCs (27.1%) as compared to follicular variant PTCs (9.4%) p = 0.001. In PTCs with and without metastases, the ratios of mutant/total BRAF alleles were 27.6% and 18.4%, respectively, (p = 0.03). In metastatic lesions percentages of mutant/total BRAF alleles were similar to those detected in primary tumors. TERTC228T and TERTC250T were found in two and one cases, respectively, and these tumors concomitantly harbored BRAFV600E. These tumors exhibited gross extra-thyroidal extension, metastases to lymph nodes, and pulmonary metastases (one case). Our results showed that dPCR allows quantitative assessment of druggable targets in PTCs and could be helpful in a molecular-based stratification of prognosis in patients with thyroid cancer.

Genomic and Transcriptomic Characterization of Papillary Microcarcinomas With Lateral Neck Lymph Node Metastases

CONTEXT

Most papillary microcarcinomas (PMCs) are indolent and subclinical. However, as many as 10% can present with clinically significant nodal metastases.

OBJECTIVE AND DESIGN

Characterization of the genomic and transcriptomic landscape of PMCs presenting with or without clinically important lymph node metastases.

SUBJECTS AND SAMPLES

Formalin-fixed paraffin-embedded PMC samples from 40 patients with lateral neck nodal metastases (pN1b) and 71 patients with PMC with documented absence of nodal disease (pN0).

OUTCOME MEASURES

To interrogate DNA alterations in 410 genes commonly mutated in cancer and test for differential gene expression using a custom NanoString panel of 248 genes selected primarily based on their association with tumor size and nodal disease in the papillary thyroid cancer TCGA project.

RESULTS

The genomic landscapes of PMC with or without pN1b were similar. Mutations in TERT promoter (3%) and TP53 (1%) were exclusive to N1b cases. Transcriptomic analysis revealed differential expression of 43 genes in PMCs with pN1b compared with pN0. A random forest machine learning-based molecular classifier developed to predict regional lymph node metastasis demonstrated a negative predictive value of 0.98 and a positive predictive value of 0.72 at a prevalence of 10% pN1b disease.

CONCLUSIONS

The genomic landscape of tumors with pN1b and pN0 disease was similar, whereas 43 genes selected primarily by mining the TCGA RNAseq data were differentially expressed. This bioinformatics-driven approach to the development of a custom transcriptomic assay provides a basis for a molecular classifier for pN1b risk stratification in PMC.

Significance of CEP78 and WDR62 gene expressions in differentiated thyroid carcinoma: Possible predictors of lateral lymph node metastasis

OBJECTIVES

This study aimed at investigating the clinical significance of CEP78 and WDR62 in differentiated thyroid carcinoma (DTC). This study also aimed at finding predictors that help in detecting patients with DTC who have high risk for lateral lymph node metastasis (LNM).

METHODS

Quantitative real-time polymerase chain reaction (RT-qPCR) was performed to examine CEP78, and WDR62 mRNA expressions in 40 tissue specimens of DTC, and 40 goiter tissue specimens. Additionally, we reviewed clinical, ultrasound, laboratory, pathological data of patients to analyze the associations between these characteristics and lateral LNM.

RESULTS

Our results demonstrated that relative CEP78 mRNA levels were significantly decreased in thyroid cancer tissues than goiter tissues (P = 0.002). ROC curve analysis confirmed the diagnostic value of CEP78 mRNA expression, providing an AUC equals to 0.698 (95% confidence intervals (CI), 0.583-0.813; P = 0.002). The relative WDR62 mRNA expression was not statistically different in DTC tissues and goiter tissues (P = 0.686). Furthermore, the DTC patients had been included to examine risk factors for lateral LNM. In multivariate analysis, the significant factors for predicting lateral LNM were low CEP78 mRNA expression (cut off value ≤0.54; P = 0.03; OR = 19.62; 95% CI, 1.3-296.23), central LNM (P = 0.011; OR = 33.6; 95% CI, 2.24-503.6) and calcifications (P = 0.023; OR = 27.187; 95% CI, 1.57-469.5).

CONCLUSIONS

CEP78 can be used as a promising molecular biomarker for differentiation between DTC and goiter tissues, in addition it might serve as a predictor of lateral LNM in DTC along with central LNM and calcifications. Unlike CEP78, WDR62 mRNA expression was not statistically different in DTC and goiter.

FMO1 gene expression independently predicts favorable recurrence-free survival of classical papillary thyroid cancer

Aim: To examine the expression profile of FMO1 in papillary thyroid cancer (PTC) and its prognostic value in recurrence-free survival (RFS). Methods: A retrospective analysis was performed using data from the Cancer Genome Atlas and Human Protein Atlas. Results: The most frequent variants of PTC had decreased FMO1 expression compared with their respective adjacent normal tissues. However, even under the best cut-off model, high FMO1 expression was only significantly associated with better RFS in classical PTC (p < 0.001), but not in other two variants. High FMO1 expression independently predicted favorable RFS (hazard ratio: 0.202; 95% CI: 0.084-0.487; p < 0.001) in classical PTC. Conclusion: High FMO1 expression might serve as a biomarker that independently predicts favorable RFS in classical PTC patients.

Precise Detection of Gene Mutations in Fine-Needle Aspiration Specimens of the Papillary Thyroid Microcarcinoma Using Next-Generation Sequencing

PURPOSE

To assess the feasibility of next-generation sequencing (NGS) to detect mutations in BRAF, RAS, TERT promoter, and TP53 genes in ultrasound-guided fine-needle aspiration (FNA) biopsy samples of the papillary thyroid microcarcinoma (PTMC).

METHODS

A total of 135 FNA samples out of 135 patients with suspected PTMC were submitted for mutation testing using NGS. NGS was successfully performed in 114 specimens, while the remaining 21 samples were excluded due to insufficient amount/poor quality of DNA and sequencing failure. Of those 114 samples, 72 who were confirmed as having PTMC by postoperative histopathology were enrolled in our study, and the other 42 who had a follow-up with ultrasound were excluded. Mutations of genes including BRAF, NRAS, HRAS, KRAS, TERT promoter, and TP53 were evaluated using NGS. The associations of gene mutations and clinicopathological characteristics of PTMC were analyzed.

RESULTS

BRAF mutation was observed in 59 (81.94%) of 72 specimens. This mutation detected in BRAF was p.V600E (c.1799T>A) in exon 15 of all 59 specimens. NRAS mutation was identified in 1 (1.39%) specimen classified as Bethesda III and pathologically confirmed as a follicular variant PTMC. There were no mutations found in TERT promoter or TP53. The tumor with a maximum diameter (D _max) larger than 5 mm was shown to be significantly correlated with the BRAF mutation in a multivariate analysis (OR 5.52, 95% CI 1.51-26.42, P = 0.033). But the BRAF mutation was not found to be significantly associated with the gender or age of patients with PTMC (P > 0.05).

CONCLUSIONS

This study demonstrated that gene mutations in FNA specimens of PTMC could be successfully analyzed with a higher sensitivity using NGS compared to conventional methods for mutation detection. BRAF mutation of p.V600E was statistically associated with PTMC with a D _max larger than 5 mm.