Clinical and pathological features and the BRAF(V600E) mutation in patients with papillary thyroid carcinoma with and without concurrent Hashimoto thyroiditis

The Association between Lymphocytic Thyroiditis and Papillary Thyroid Cancer Harboring Mutant BRAF: A Systematic Review and Meta-Analysis

Background: Papillary thyroid cancer (PTC) and lymphocytic thyroiditis (LT) co-occur with a prevalence of about 30%. PTC harboring BRAFV600E (PTC-BRAF) confers a worse prognosis, but it is unclear if LT alters prognostic features and recurrence of PTC. Objective: We compared the prevalence of PTC-BRAF with and without LT. The risk of adverse pathological features in (i) PTC in the presence and absence of BRAF mutation, irrespective of LT status, was compared to (ii) PTC in the presence and absence of LT, irrespective of BRAF status. Methods: We searched PubMed, Embase, and Web of Science Core Collection for observational studies published from 2010 to June 2023 on adult patients with PTC. The search strategy yielded 47 studies with relevant data. Data of baseline characteristics, clinicopathological features, and the quality assessment tool were extracted by two reviewers. The study was registered with PROSPERO (CRD42023437492). Results: Of the 47 studies, 39 studies with a total cohort of 28 143, demonstrated that the odds of PTC-BRAF were significantly lower in the presence of LT compared to its absence (odds ratio [OR] 0.53, 95% confidence interval [CI]: 0.48-0.58, p < 0.00001). In PTC-BRAF patients, there was a positive association of central neck nodal disease (CNND), PTC > 1 cm, extra-thyroidal extension, American Joint Committee on Cancer (AJCC) Stage 3-4, and multifocality with pooled ORs of 1.54 (95% CI: 1.16-2.04), 1.14 (95% CI: 0.82-1.58), 1.66 (95% CI: 1.40-1.97), 1.53 (95% CI: 1.35-1.75), and 1.24 (95% CI: 1.11-1.40) respectively, compared to wild-type PTC, irrespective of LT status. In the same studies, PTC with LT patients had lower pooled ORs of 0.64 (95% CI: 0.51-0.81) for CNND, 0.83 (95% CI: 0.73-0.95) for PTC > 1 cm, 0.71 (95% CI: 0.58-0.86) for ETE, 0.84 (95% CI: 0.75-0.94) for AJCC Stage 3-4 compared to PTC without LT, irrespective of BRAF status. PTC recurrence was not affected by BRAF or LT, with pooled ORs of 1.12 (95% CI: 0.66-1.90, p = 0.67) and 0.60 (95% CI: 0.28-1.30, p = 0.20) respectively. Similar results were seen with recurrence expressed as hazard ratio in this limited data-set. Conclusion: The odds of PTC-BRAF are significantly lower in the presence of LT than without. PTC with LT, irrespective of BRAF status, was significantly associated with better prognostic factors. Further studies are required to evaluate if LT inhibits PTC-BRAF, and whether this is relevant to the role of immunotherapy in advanced thyroid cancer.

Clinical impact of coexistent chronic lymphocytic thyroiditis on central lymph node metastasis in low- to intermediate-risk papillary thyroid carcinoma: The MASTER study

BACKGROUND

The clinicopathological impact of chronic lymphocytic thyroiditis on patients with papillary thyroid carcinoma patients is still controversial. This study aimed to evaluate the clinicopathologic differences and risk factors for central lymph node metastasis based on the presence of coexistent chronic lymphocytic thyroiditis in patients with low- to intermediate-risk papillary thyroid carcinoma.

METHODS

The medical records of 1,022 patients with low- to intermediate-risk papillary thyroid carcinoma who underwent lobectomy and central neck dissection between June 2020 and March 2022 were reviewed. Differences in clinicopathological factors were analyzed in patients with papillary thyroid carcinoma with or without chronic lymphocytic thyroiditis. Furthermore, risk factors for central lymph node metastasis in patients with low- to intermediate-risk papillary thyroid carcinoma with or without chronic lymphocytic thyroiditis were evaluated.

RESULTS

Among the 1,022 patients with low to intermediate-risk papillary thyroid carcinoma, 102 (10.0%) had coexisting chronic lymphocytic thyroiditis. Female sex (odds ratio = 3.536, P = .001, 95% confidence interval 1.781-8.069), a multifocal tumor (odds ratio = 2.162, P = .001, 95% confidence interval 1.358-3.395), and angiolymphatic invasion (odds ratio = 0.365, P < .001, 95% confidence interval 0.203-0.625) were independent factors associated with patients who had coexisting chronic lymphocytic thyroiditis compared to those without chronic lymphocytic thyroiditis. There were 358 (35%) patients who had central lymph node metastasis. Multivariate analysis showed that younger age (odds ratio = 0.667, P = .013, 95% confidence interval 0.482-0.555), male sex (odds ratio = 0.549, P < .001, 95% confidence interval 0.402-0.751), tumor size >1 cm (odds ratio = 1.454, P = .022, 95% confidence interval 1.053-2.003), extrathyroidal extension (odds ratio = 1.874, P < .001, 95% confidence interval 1.414-2.486), and angiolymphatic invasion (odds ratio = 3.094, P < .001, 95% confidence interval 2.339-4.101) were risk factors for central lymph node metastasis. Angiolymphatic invasion (odds ratio = 11.184, P < .001, 95% confidence interval 3.277-46.199) was identified as the sole independent risk factor for central lymph node metastasis in patients with papillary thyroid carcinoma with coexisting chronic lymphocytic thyroiditis.

CONCLUSION

Our data suggest that patients with low to intermediate-risk papillary thyroid carcinoma with coexistent chronic lymphocytic thyroiditis exhibit different clinical features than patients with papillary thyroid carcinoma without chronic lymphocytic thyroiditis. Additionally, the presence of chronic lymphocytic thyroiditis may be considered a potential factor against central lymph node metastasis.

Prevalence and Impact of BRAF mutation in patients with concomitant papillary thyroid carcinoma and Hashimoto's thyroiditis: a systematic review with meta-analysis

Background

Evidence suggests that patients with Hashimoto thyroiditis (HT) are at significantly higher risk of developing papillary thyroid cancer (PTC). However, the course of PTC in patients with both diseases concomitantly has been found to be more indolent than conventional PTC. Additionally, it has been well proven that BRAF mutation results in an aggressive course of PTC. The aims of this meta-analysis were to identify prevalence of BRAF mutation and its impact on clinicopathological features in patients with concomitant PTC-HT.

Methods

Medline, Cochrane Library, Scopus, and Web of Science were searched until 16.09.2022, resulting in 227 articles, of which nine studies were included. Summary estimates, comparing patients with (A) BRAF (+) PTC-HT versus BRAF (+) PTC, and (B) BRAF (+) PTC-HT versus BRAF (-) PTC-HT, were generated with Review Manager 5.0.

Results

In total, 6395 patients were included in this review. PTC-HT patients had significantly less BRAF mutation than PTC patients (Odds Ratio (OR) (95% Confidence Interval (CI))=0.45 (0.35-0.58), P<0.001). BRAF (+) PTC-HT patients were significantly more likely to have multifocal lesions (OR (95% CI)=1.22 (1.04-1.44), P=0.01) but less likely to have lymph node metastasis (OR (95% CI)=0.65 (0.46-0.91), P=0.01) and extrathyroidal extension (OR (95% CI)=0.55 (0.32-0.96), P=0.03) compared to BRAF (+) PTC patients. BRAF (+) PTC-HT patients were more likely to have multifocal lesions (OR (95% CI)=0.71 (0.53-0.95), P=0.02), lymph node metastasis (OR (95% CI)=0.59 (0.44-0.78), P<0.001) and extrathyroidal extension (OR (95% CI)=0.72 (0.56-0.92), P=0.01) compared to BRAF (-) PTC-HT patients.

Conclusion

This meta-analysis highlights that the lower prevalence of BRAF mutation in patients with PTC-HT than conventional PTC may explain the indolent clinicopathological course in this cohort.

Hashimoto's Thyroiditis: A Protective Factor against Recurrence in BRAF-Wild Type Differentiated Thyroid Carcinoma

A recent work analyzing the concomitant factors BRAF mutation (risk factor) and Hashimoto's thyroiditis (HT) (protective factor) found that the presence of HT reduced lymph node metastasis in BRAF-mutated papillary thyroid carcinoma. Whether this notion is upheld with respect to disease recurrence and differentiated thyroid carcinoma (DTC), however, is unknown. We aimed to investigate the effect of underlying HT in DTC patients and its influence on recurrence with a specific emphasis in BRAF-mutated tumors. A total of 469 patients were included. Patients were stratified according to BRAF and HT status. Multivariate regression analysis was conducted to determine protective and risk factors of disease recurrence in patients with DTC. HT was associated with less-aggressive carcinomas including more frequent microcarcinomas (HT: 45.0% vs. no-HT: 34.0%, p = 0.02), less lymph node involvement (HT: 16.4% vs. no-HT: 26.1%, p = 0.02), and less disease recurrence (HT: 2.9% vs. no-HT: 11.9%, p = 0.002). BRAF mutation was also significantly associated with higher rates of lymph node involvement (BRAF-mutant: 41.9% vs. BRAF-wild type: 14.6%, p < 0.001) and almost two times the rate of recurrence (BRAF-mutant: 14.9% vs. BRAF-wild type: 6.5%, p = 0.004). Underlying HT was the only protective factor determined, reducing the odds of developing recurrence by 70% (HR: 0.30, 95%CI: 0.11-0.88). In the BRAF-wild type cohort, regression analysis continued to determine HT as a protective factor (p = 0.03). However, in the BRAF-mutant cohort, HT was no longer an independent protective factor (p = 0.20) against recurrence. Sub-group regression analysis, including PTC patients, similarly found HT as a protective factor only in BRAF-wild type patients (p = 0.039) and not BRAF-mutant (p = 0.627). The presence of underlying HT is associated with less aggressive tumors and is an independent protective factor against DTC recurrence, reducing the risk by 70%. HT remains a protective factor in BRAF-wild type carcinoma, but not in patients with BRAF-mutant carcinoma. HT may potentially be considered as a parameter which enhances American Thyroid Association patient risk stratification.

Association between Hashimoto thyroiditis and clinical outcomes of papillary thyroid carcinoma: A meta-analysis

Objective

To assess association between Hashimoto thyroiditis (HT) and clinical outcomes of papillary thyroid carcinoma (PTC).

Methods

Databases including Pubmed, Embase, Cochrane Library, and Web of Science were searched. Weighed mean differences (WMDs) and odds ratios (ORs) were used to evaluate association between HT and clinical outcomes of PTC, and the effect size was represented by 95% confidence intervals (CIs). Heterogeneity test was performed for each indicator. If the heterogeneity statistic I²≥50%, random-effects model analysis was carried out, otherwise, fixed-effect model analysis was performed. Sensitivity analysis was performed for all outcomes, and publication bias was tested by Begg’s test.

Results

Totally 47,237 patients in 65 articles were enrolled in this study, of which 12909 patients with HT and 34328 patients without HT. Our result indicated that PTC patients with HT tended to have lower risks of lymph node metastasis (OR: 0.787, 95%CI: 0.686–0.903, P = 0.001), distant metastasis (OR: 0.435, 95%CI: 0.279–0.676, P<0.001), extrathyroidal extension (OR: 0.745, 95%CI: 0.657–0.845, P<0.001), recurrence (OR: 0.627, 95%CI: 0.483–0.813, P<0.001), vascular invasion (OR: 0.718, 95%CI: 0.572–0.901, P = 0.004), and a better 20-year survival rate (OR: 1.396, 95%CI: 1.109–1.758, P = 0.005) while had higher risks of multifocality (OR: 1.245, 95%CI: 1.132–1.368, P<0.001), perineural infiltration (OR: 1.922, 95%CI: 1.195–3.093, P = 0.007), and bilaterality (OR: 1.394, 95%CI: 1.118–1.739, P = 0.003).

Conclusions

PTC patients with HT may have favorable clinicopathologic characteristics, compared to PTCs without HT. More prospective studies are needed to further elucidate this relationship.

Chronic Lymphocytic Thyroiditis and Aggressiveness of Pediatric Differentiated Thyroid Cancer

OBJECTIVES/HYPOTHESIS

Hashimoto's Thyroiditis (HT) is a common cause of hypothyroidism. Among adults with differentiated thyroid cancer (DTC), HT appears to be associated with less severe disease burden. In the absence of information regarding HT and disease burden among children with DTC, we assessed the relationship between pediatric DTC severity and HT.

STUDY DESIGN

Retrospective cohort.

METHODS

Charts from 90 pediatric patients who underwent surgical removal of DTC from 2002 to 2017 at tertiary-care children's hospital were reviewed. Demographic, clinical, surgical, pathology, and outcome details were compared between patients with and without HT. Consistency among diagnostic modalities of HT was also evaluated.

RESULTS

Median age at presentation was 16.0 years (range 4.2-18.9 years). Twenty-two patients were male (24%). Forty-five patients (50%) had HT based on presence of thyroid autoantibodies and/or surgical pathology findings and 45 patients did not have HT. Patients with HT had increased odds of microcalcifications (odds ratio [OR]: 3.01, P = .031) and decreased odds of palpable nodules (OR: 0.212, P = .024) and T2 lesions (vs. T1) (OR: 0.261, P = .015) compared with non-HT. No significant differences in demographics and the incidence of multifocality, extrathyroidal extension, lymphovascular invasion, lymph node or pulmonary metastases, disease recurrence, or radioactive iodine treatment were found between the two groups. Thyroglobulin/thyroid peroxidase autoantibodies and surgical pathology indicative of HT were concordant in 82.4% (κ = 0.635, P < .001).

CONCLUSION

HT was present in 50% of children with DTC. Patients with DTC and HT presented with smaller tumors compared to non-HT patients. No significant differences in other markers of disease aggressiveness were found between the two groups.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

The Effects of Chronic Lymphocytic Thyroiditis on Clinicopathological Factors In Papillary Thyroid Cancer

INTRODUCTION

This study evaluated the impact of chronic lymphocytic thyroiditis (CLT) on clinicopathological parameters, prognostic outcome and initial treatment responses in patients with papillary thyroid cancer (PTC).

METHODS

A retrospective review was made of 1409 patients with PTC, comprising 443 pathology proven PTC patients with CLT and 447 PTC patients without CLT.

RESULTS

The median follow-up time was 58 (8-380) months and the median age at the time of diagnosis was 43 years. The diagnosis age was significantly lower in patients with CLT (42 vs. 45 years, p:0.001). The preoperative TSH level was found to be significantly higher in CLT patients (1.71 mIU/L vs. 1.28 mIU/L, p<0.001). Multifocality, capsular, lymphovascular and perineural invasion were detected at a higher rate in the group with CLT than in the group without CLT (p:0.015, p:0.024, p:0.004, p:0.039, respectively). No difference was found between the two groups in terms of tumor size, bilaterality, extrathyroidal invasion, lymph node metastasis, disease stage and response to treatment (p>0.05).

CONCLUSION

The results of the present study demonstrated that coexistence of PTC and CLT is very frequent. It was found that patients with PTC and CLT coexistence were diagnosed at an earlier age and the TSH level was higher. Contrary to previous studies, no positive effect of CLT and PTC combination was detected on any clinicopathological factor. In addition, lymphovascular and perineural invasion, which had negative effects on prognosis, was more common in the CLT group.

Analysis of risk factors for lateral lymph node metastasis in papillary thyroid carcinoma: a retrospective cohort study

Objective

To investigate the risk factors for lateral lymph node metastasis (LLNM) in papillary thyroid carcinoma (PTC).

Methods

A retrospective analysis of 209 patients with PTC who underwent primary surgery at the Beijing Friendship Hospital affiliated with Capital Medical University from November 2014 to November 2018 was performed. The patients were divided into the LLNM group and the non‐LLNM group. The clinical and pathological characteristics of the patients were analysed. The risk factors for LLNM were analysed by univariate and multivariate analyses.

Results

The incidence of LLNM was 13.4% in PTC patients. Univariate analysis showed that the maximum diameter of the primary tumour > 2 cm (P < 0.001), bilateral primary tumour (P = 0.020), extrathyroidal extension (ETE) (P < 0.001), central lymph node metastasis (CLNM) (P < 0.001), and CLNM number ≥ 5 (P < 0.001) were significantly associated with LLNM. Multivariate logistic regression analysis showed that the maximum diameter of the primary tumour > 2 cm, ETE, and CLNM were independent risk factors for LLNM (OR values were 3.880, 5.202, and 4.474, respectively). There were 6 patients with skip lateral cervical lymph node metastasis, accounting for 21% of all LLNM patients.

Conclusion

This study revealed several independent risk factors for predicting LLNM in PTC patients, such as the maximum diameter of the primary tumour > 2 cm, ETE and CLNM. Lateral neck dissection may be recommended in PTC patients with those risk factors. Paying attention to the occurrence of skip lateral cervical lymph node metastasis during the clinical diagnosis and treatment processes is necessary.

The Association Between Chronic Lymphocytic Thyroiditis and the Progress of Papillary Thyroid Cancer

BACKGROUND

Whether chronic lymphocytic thyroiditis (CLT) influences the risk of development and the progression of papillary thyroid cancer (PTC) remains uncertain. We investigated the effects of CLT on the clinicopathologic features and prognosis of PTC.

METHODS

Two thousand nine hundred twenty-eight consecutive patients with PTC treated between 2009 and 2017 were divided into two groups: one with chronic lymphocytic thyroiditis and one without; 1174 (40%) of the patients had coincident CLT.

RESULTS

In univariate analysis, CLT correlated positively with small tumor size, frequent extrathyroidal extension, multifocal diseases, and p53 but negatively with central lymph node (LN) metastasis and BRAF mutation. In multivariate analysis, CLT was associated with extrathyroidal extension and multifocal disease; however, it was not a prognostic factor for recurrence even though it was associated with two aggressive factors. Compared with patients with PTC alone, there were more retrieved central LNs in the PTC + CLT group, and these patients also underwent more invasive diagnostic tests such as fine needle aspiration cytology and frozen biopsy of LN.

CONCLUSIONS

The CLT patients with PTC had better behavior features and prognoses than did those with PTC alone despite frequent multifocality and extrathyroidal extension. However, precaution may be necessary to avoid performing invasive diagnostic procedures for lateral LN metastasis and to manage the patients appropriately.

Prevalence of BRAFV600E mutation in Asian series of papillary thyroid carcinoma-a contemporary systematic review

Papillary thyroid carcinoma (PTC), the most common malignancy of the endocrine system, is frequently driven by BRAFV600E mutation, which was reported in 35-60% cases in Western series. Numerous studies have recently emerged from Asian countries and regions; however sufficient summary is lacking to date. BRAF mutation serves as a diagnostic and prognostic tool in thyroid cancer, therefore establishing a rate of BRAF on the national scale could be of practical significance. We performed systematic reviews of available literature to investigate the prevalence of BRAF mutation in series of PTC from various Asian countries and regions. Out of the total 3,966 reports identified via initial screening, 138 studies encompassing over 40,000 PTCs were included for the final analysis. A vast majority (90.2%) of PTCs with known BRAF status were from East Asia, including China, South Korea, and Japan, with BRAF mutation rates of 71.2%, 75.5%, and 70.6%, respectively. Less abundant Indian and Saudi Arabian series found 45.6% and 46.3% prevalence of BRAFV600E in PTC, respectively. Much limited evidence was available from Thailand, Iran, Kazakhstan, Taiwan, Singapore, Indonesia, Hong Kong, Philippines, Vietnam, Iraq, and Myanmar. No relevant publications were found from other highly populated countries, such as Pakistan, Bangladesh, and Malaysia. After grouping by geographic region, we found that the highest rate of BRAFV600E was reported in the PTC series from East Asia (76.4%). Much lower rate (45-48%) was seen in PTC cohorts from South Asia, Central Asia, and the Middle East while the Southeast Asian series were in between (57%). Further subgroup analysis revealed that studies employing fresh frozen tissue and fine-needle aspirates showed higher rates of BRAF compared to those used formalin-fixed paraffin-embedded tissues. We found that the PTC series enrolled patients' cohorts after 2010 demonstrated a higher rate of BRAF compared to the earlier series. Finally, pediatric PTCs had lower BRAF prevalence compared to the baseline rate for the country. In conclusion, despite considerable among and within countries heterogeneity, the Asian PTC series showed a higher prevalence of BRAFV600E mutation than that in Western series. Causes of geographic heterogeneity, whether genuine (etiology, genetics) or methodology-related should be further investigated.

Atypia of undetermined significance/follicular lesion of undetermined significance: Asian vs. non-Asian practice, and the Singapore experience

The Bethesda System for Reporting Thyroid Cytopathology has paved the way for comparisons of the practice of thyroid cytology in many different regions. However, there have been comparatively few studies documenting differences between Asian and non-Asian practice. Here, we aim to compare a few key parameters between the two regions, focusing on the indeterminate category of atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS). We compared its incidence, resection rates (RRs), risk of malignancy (ROM), rate of repeat fine needle aspiration (rFNA), ROMs of cytomorphologic subcategories of nuclear atypia (AUS-N) vs. architectural atypia (AUS-A), and, finally, the incidence of papillary thyroid carcinoma (PTC) vs. follicular neoplasms (FNs) in resected AUS/FLUS cases in Asian and non-Asian regions. Where possible, these metrics were compared with the Singapore experience from a tertiary referral institution. While the incidence of AUS/FLUS was similar in both regions, we found geographical differences in the RRs and ROMs, which may reflect a higher collective threshold for surgery in Asian countries. However, both cohorts showed higher ROMs in the AUS-N subcategory as compared to the AUS-A subcategory, supporting the subclassification of the AUS/FLUS based on the presence of nuclear atypia. We also observed a higher incidence of AUS-N coupled with a higher incidence of PTC in resected AUS/FLUS nodules in Asian cohorts, while AUS-A and follicular-patterned neoplasms featured more prominently in the non-Asian cohorts. These incidences may account for the starkly different molecular approaches that we noted-in Asian (chiefly Korean and Chinese) centers, BRAF mutational analysis was favored, while gene panels and gene expression classifiers were more frequently applied in non-Asian centers (chiefly in the United States of America). Overall, the data from Singapore appears more closely aligned to non-Asian trends, despite its geographical location in Southeast Asia and its predominantly Asian population. We conclude that there is significant heterogeneity in the outcomes of the AUS/FLUS categories between and within regions, which is only partially explained by regional variations, and may also reflect different regional diagnostic and management practices. This highlights the importance of understanding the local context in the interpretation of indeterminate Bethesda categories, rather than adopting a "one-size fits all" approach.

Uncommon Site of Metastasis and Prolonged Survival in Patients with Anaplastic Thyroid Carcinoma: A Systematic Review of the Literature

Simple Summary

The therapeutic strategies employed for anaplastic thyroid cancer patients seems to be insufficient to prolong their survival, but some characteristics could predict a good prognosis, so that, starting from our experience we offer a systematic review of the literature to better understand anaplastic thyroid cancers behavior and their prognostic factors, in order to recognize and select the patients with the higher probability of better outcome even if metastatic. Moreover, we described an uncommon site of metastasis in order to improve scientific knowledge about this rare and highly aggressive pathology.

Abstract

Anaplastic thyroid carcinoma (ATC) is a very rare, highly aggressive malignant thyroid tumor with an overall survival from 3 to 5 months in most of the cases. Even the modern and intensive treatments seem not to be enough to provide a cure, also for the resectable ones, and the role of chemotherapy is still unclear but does not seem to prolong survival. Nevertheless, some patients survive longer and have a better outcome, even in the presence of metastasis, than what the literature reports. We present the case of a 64-year-old female affected by ATC, treated on February 2018 with surgery followed by chemoradiation. One year after surgery, the patient developed a subcutaneous recurrence that was radically resected and is still alive 29 months after the diagnosis. We propose a systematic review of the literature to deepen the knowledge of the prognostic factors of ATC with the aim to recognize and select the patients with a better outcome, even if metastatic, and to describe a very uncommon site of metastatization.

Characterization of BRAF mutation in patients older than 45 years with well-differentiated thyroid carcinoma

Introduction

Papillary thyroid carcinoma is the most frequent endocrine neoplasia and its incidence has tripled over the past 35 years. Although papillary thyroid carcinoma carries a good prognosis, 10%−30% of patients still develop recurrence and metastasis. Some clinical and genetic features are associated with worse prognosis. The most frequent mutation is the BRAF p.V600E, which has been associated with many clinical features of poor prognosis. However, many studies have produced controversial results without any association between BRAF mutation and clinicopathological features of poor prognosis.

Objective

Since the prognostic value of BRAF mutations remains controversial, this study aims to investigate the importance of this mutation in therapeutic decisions for papillary thyroid carcinoma.

Methods

Therefore, we evaluated whether the presence of BRAF mutation is associated with features of poor prognosis in 85 patients with papillary thyroid carcinoma older than 45 years treated at A.C. Camargo Cancer Center, from 1980 to 2007. BRAF mutation was evaluated by pyrosequencing. Statistical analysis was performed using SPSS.

Results

The mean age of patients was 54 years (range: 45 − 77 years), 73 were women (85.8%) and 12 were men (14.2%). Among them, 39 cases (45.9%) presented extrathyroidal extension and 11 cases had recurrent disease. BRAF mutation was detected in 57 (67%) patients. No significant association was observed between BRAF mutation and gender (p  = 0.743), age (p  = 0.236), N-stage (p  = 0.423), vascular and perineural infiltration (p  = 0.085 or multifocality (p  = 1.0). Although not statistically significant, the majority of patients with recurrent disease were BRAF positive (9 out of 11) (p  = 0.325). Patients affected by BRAF mutation are associated with tumors larger than 1 cm (p  = 0.034) and with extrathyroidal extension (p  = 0.033).

Conclusion

Although BRAF testing is widely available, there are no consistent data to support improvement in outcomes from incorporating it into therapeutic decision for thyroid cancer.

Coexisting Germline CHEK2 and Somatic BRAFV600E Mutations in Papillary Thyroid Cancer and Their Association with Clinicopathological Features and Disease Course

BRAF^V600E is the most common somatic mutation in papillary thyroid carcinoma (PTC) and the majority of evidence indicates that it is associated with an aggressive clinical course. Germline mutations of the CHEK2 gene impair the DNA damage repair process and increase the risk of PTC. Coexistence of both mutations is expected to be associated with poorer clinical course. We evaluated the prevalence of concomitant CHEK2 and BRAF^V600E mutations and their associations with clinicopathological features, treatment response, and disease course in PTC patients. The study included 427 unselected PTC patients (377 women and 50 men) from one center. Relationships among clinicopathological features, mutation status, treatment response, and disease outcomes were assessed. Mean follow-up was 10 years. CHEK2 mutations were detected in 15.2% and BRAF^V600E mutations in 64.2% patients. Neither mutation was present in 31.4% cases and both BRAF^V600E and CHEK2 mutations coexisted in 10.8% patients. No significant differences in clinicopathological features, initial risk, treatment response, or disease outcome were detected among these patient groups. CHEK2 mutations were significantly associated with older age, while BRAF^V600E was significantly associated with older age and extrathyroidal extension. The coexistence of both mutations was not associated with more aggressive clinicopathological features of PTC, poorer treatment response, or disease outcome.

Association Between BRAFV600E Mutation and the American College of Radiology Thyroid Imaging, Reporting and Data System in Solitary Papillary Thyroid Carcinoma

RATIONALE AND OBJECTIVES

The purpose of this study was to evaluate the associations between BRAF^V600E mutation, the American College of Radiology (ACR) thyroid imaging, reporting and data system (TI-RADS) on ultrasound and clinicopathological characteristics in patients with a solitary papillary thyroid carcinoma (PTC).

MATERIALS AND METHODS

This retrospective study included 397 patients with a solitary PTC, proved pathologically. BRAF^V600E mutation status was detected in postoperative samples by real-time fluorescent polymerase chain reaction. Associations of BRAF^V600E mutation with the ACR TI-RADS and clinicopathological characteristics were analyzed.

RESULTS

In this study, the incidence of BRAF^V600E mutation was 81.4% (323/397) in patients with a solitary PTC. Univariate analyses showed that BRAF^V600E mutation was significantly associated with margin, higher ACR TI-RADS point scores, and Hashimoto's thyroiditis. In multivariate analyses, lobulated or irregular margin was independently associated with BRAF^V600E mutation in total solitary PTC. Furthermore, both in total solitary PTC and papillary thyroid microcarcinoma, BRAF^V600E mutation was associated with ACR TI-RADS point scores, which was positively correlated with the risk of BRAF^V600E mutation. There was no significant relationship between BRAF^V600E mutation and ACR TI-RADS point scores in PTC >10 mm. In addition, Hashimoto's thyroiditis had a significant negative association with BRAF^V600E mutation.

CONCLUSION

A lobulated or irregular margin of the thyroid nodule is independently associated with BRAF^V600E mutation in patients with PTC. In addition, higher ACR TI-RADS point scores is an independent risk factor for BRAF^V600E mutation, and ACR TI-RADS point scores is positively associated with the risk of BRAF^V600E mutation in solitary PTC, especially in papillary thyroid microcarcinoma. Our findings may be helpful for preoperative identification and medical management of PTC patients with BRAF^V600E mutation.

Associations between Hashimoto Thyroiditis and Clinical Outcomes of Papillary Thyroid Cancer: A Meta-Analysis of Observational Studies

BACKGROUND

Epidemiological studies have suggested an association between Hashimoto thyroiditis (HT) and papillary thyroid cancer (PTC) development. Other studies, however, have reported a protective role of HT against PTC progression. Through this updated meta-analysis, we aimed to clarify the effects of HT on the progression of PTC.

METHODS

We searched citation databases, including PubMed and Embase, for relevant studies from inception to September 2017. From these studies, we calculated the pooled odds ratios (ORs) of clinicopathologic features and the relative risk (RR) of PTC recurrence with 95% confidence intervals (CIs) using the Mantel-Haenszel method. Additionally, the Higgins I² statistic was used to test for heterogeneity.

RESULTS

The meta-analysis included 71 published studies with 44,034 participants, among whom 11,132 had HT. We observed negative associations between PTC with comorbid HT and extrathyroidal extension (OR, 0.74; 95% CI, 0.68 to 0.81), lymph node metastasis (OR, 0.82; 95% CI, 0.72 to 0.94), distant metastasis (OR, 0.49; 95% CI, 0.32 to 0.76), and recurrence (RR, 0.50; 95% CI, 0.41 to 0.61).

CONCLUSION

In this meta-analysis, PTC patients with HT appeared to exhibit more favorable clinicopathologic characteristics and a better prognosis than those without HT.

BRAF mutation in papillary thyroid cancer-Prevalence and clinical correlation in a South-East Asian cohort

OBJECTIVE

BRAF mutation is the commonest mutation seen in papillary thyroid cancer (PTC), but its prevalence and clinical significance vary across countries. We aim to evaluate the prevalence and clinico-pathological correlation of BRAF mutation in PTC patients at our centre.

STUDY DESIGN

Retrospective cohort study of 75 consecutive archival thyroid specimens, whereby BRAF mutation was detected using a polymerase chain reaction (PCR) technique and correlated with clinical and pathological features and outcomes.

SETTING

Tertiary university hospital in Singapore.

PARTICIPANTS

A total of 75 consecutive histologically proven archival thyroid specimens from patients who underwent thyroidectomy for PTC were accrued for this study.

MAIN OUTCOME MEASURES

Main outcome is to determine the prevalence of the BRAF mutation in our South-East Asian population. Secondary aim is to correlate the mutational status with adverse pathological features like histological variants, multi-focality, lymphovascular invasion and extra-thyroidal extension, clinical features like demographics, TNM stage, recurrence and survival, as well as treatment details like type of surgery performed and radioiodine doses.

RESULTS

BRAF mutation was detected in 56% (42/75) of PTC. All but one BRAF-mutated PTC had the BRAFV600E mutation. BRAF-mutated tumours were associated with an advanced T-stage (P = 0.049) and were more likely to have a central neck dissection (P = 0.036). There was no significant correlation between BRAF mutation status and clinical outcomes.

CONCLUSION

The prevalence of BRAF mutation is 56%. BRAF mutation-positive tumours were associated with locally advanced disease, but not poorer survival.

Thyroid nodules and cancer in children and adolescents affected by Hashimoto's thyroiditis

OBJECTIVE

To investigate the rates of thyroid nodules and cancer in pediatric cases of Hashimoto's thyroiditis (HT) in Korea.

METHODS

We retrospectively reviewed 89 pediatric and adolescent patients (age, 3-18.0 years) with HT who underwent thyroid ultrasonography (US) at our institution from February 2006 to July 2016. The diagnosis of HT was based on the presence of thyroid autoantibodies. The presence of any thyroid nodules with US and cytopathologic features was analyzed. The malignancy rate was also determined.

RESULTS

Thyroid nodules were in 20 of the 89 patients (22.4%). Eight of these 20 patients (40%) had colloid cysts, two (10%) had nodular hyperplasia, one (5%) had follicular adenoma, and two (10%) had lymphocytic thyroiditis. Seven of the 89 patients (7.9%) were confirmed to have a malignancy, all of which were papillary thyroid carcinoma (PTC); of those, five patients had diffuse sclerosing variant PTC, and two had conventional PTC on pathology.

CONCLUSION

The prevalence of thyroid nodules in children and adolescents with HT was 22.4%. The malignancy rate of children with HT was 7.9%. The malignancy rate among thyroid nodules was 35%, which is higher than the 26% rate generally reported for children with nodules. Therefore, using thyroid US to survey known or suspected thyroid nodules might be helpful in children and adolescents with HT and may provide further useful diagnostic information. Advances in knowledge: Thyroid US could help to assess HT patients who have known or suspected thyroid nodules.

Association between diffuse lymphocytic infiltration and papillary thyroid cancer aggressiveness according to the presence of thyroid peroxidase antibody and BRAFV600E mutation

BACKGROUND

Diffuse lymphocytic infiltration (DLI) is frequently found with papillary thyroid cancer (PTC), so there has been long interest in how it affects the characteristics of PTC. This purpose of this study was to define the association between DLI and PTC aggressiveness according to thyroperoxidase antibody (TPOAb) and B-type Raf (BRAF)^V600E mutation positivity.

METHODS

There were 1879 patients with PTC who underwent surgery and were enrolled in this study. Clinicopathologic characteristics were compared between groups according to the presence of DLI and TPOAb. Multiple logistic regression analysis was conducted to assess odds ratio (OR) for each dependent variable (BRAF^V600E mutation, tumor size >1.0 cm, multifocality, extrathyroidal extension, and lymph node metastasis) of each group according to the presence of DLI and TPOAb, with the group with neither DLI or TPOAb (DLI-negative TPOAb-negative PTC) as the reference.

RESULTS

The DLI-positive PTC showed more frequent multifocality and less frequent BRAF^V600E mutation than DLI-negative PTC. Among patients with DLI-positive PTC, extrathyroidal extension and BRAF^V600E mutation was less frequent when serum TPOAb was positive. In multiple logistic regressions, DLI-positive TPOAb-positive PTC showed a high OR for multifocality (1.410; P = .017), but low ORs for BRAF^V600E mutation (0.521; P < .001) and extrathyroidal extension (0.691; P = .008). The patients with DLI-positive TPOAb-positive PTCs showed a high OR for multifocality (1.588; P = .002), and high ORs for tumor size >1.0 cm (2.205; P = .019) and lymph node metastasis (2.005; P = .032) in subgroup analyses of PTC with wild-type BRAF. The DLI-negative TPOAb-positive group was not associated with any tumor aggressiveness-related variables.

CONCLUSION

Although DLI was associated with multifocality regardless of TPOAb positivity, it was associated with an indolent feature when TPOAb was positive but with aggressive features in PTC with wild-type BRAF when TPOAb was negative. The TPOAb and BRAF status may help to define the clinical implication of lymphocytic infiltration found with PTC.

Chronic lymphocytic thyroiditis (CLT) has a positive prognostic value in papillary thyroid cancer (PTC) patients: the potential key role of Foxp3+ T lymphocytes

BACKGROUND

An impact of chronic lymphocytic thyroiditis (CLT) on papillary thyroid cancer (PTC) outcome has long been advocated but it is still controversial.

PURPOSE

The aim of this study was to evaluate the prognostic value of CLT in a retrospective cohort of PTC patients and to characterize the lymphocytic subpopulations and infiltrate (LI).

MATERIALS AND METHODS

We assessed 375 PTC patients, aged 45.2 ± 16.4 years, and treated with thyroidectomy and radioiodine remnant ablation, with a mean follow-up of 6.28 ± 3.86 years. In a subgroup of patients (n = 81) tissue sections were reviewed for the presence of CLT or lymphocytes associated with tumor in absence of background thyroiditis (TAL); cytotoxic CD8+/regulatory Foxp3+ T lymphocyte (CD8+/Foxp3+) ratio was characterized by immunohistochemistry: a low ratio is suggestive of a less effective anti tumor immune response.

RESULTS

Seventy-five/375 patients (20%) had a histological diagnosis of CLT and showed at the last follow-up a significantly better outcome compared to those with no CLT (cure rate: 91.8 versus 76.3%, p = 0.003). LI was characterized in 81 PTC patients (24 with CLT and 57 with TAL): the peri-tumoral CD8+/Foxp3+ ratio was lower in patients not cured at the final evaluation.

CONCLUSIONS

Our data suggest that concurrent CLT has a protective effect on PTC outcome and that the imbalance between cytotoxic and regulatory T lymphocytes in the peri-tumoral TAL may affect the tumor-specific immune response favoring a more aggressive behavior of cancer.

Effects of Chronic Lymphocytic Thyroiditis on the Clinicopathological Features of Papillary Thyroid Cancer

BACKGROUND

The effects of chronic lymphocytic thyroiditis (CLT) on the presentation and outcome of papillary thyroid carcinoma (PTC) have long been a topic of controversy.

OBJECTIVE

To evaluate the effect of coexistent CLT on the clinicopathological features of PTC.

DESIGN

Retrospective study.

PATIENTS

All patients with PTC who had been followed by the 2 co-investigators (Juan Rivera and Richard J. Payne) between 2006 and 2011 were included.

RESULTS

CLT was present in 35% (166) of the included patients and was associated with a higher proportion of patients with TNM stage I (p = 0.027) and fewer patients with persistent disease (p = 0.014) in comparison with the PTC-only group. Analysis of the data based on age (<45 or >45 years) revealed that in the older group, the presence of CLT was associated with fewer patients with persistent disease (p = 0.03) and capsular invasion (p = 0.05). However, in patients <45 years of age, the presence of CLT was associated with more capsular invasion (p = 0.003) and extrathyroidal extension (p = 0.004) compared with the PTC-only group.

CONCLUSIONS

CLT in patients with PTC was associated with lower-stage disease and less disease persistence in patients >45 years of age. In patients <45 years, the presence of CLT appeared to be associated with unfavorable pathological features.

Influence of coexistent Hashimoto's thyroiditis on the extent of cervical lymph node dissection and prognosis in papillary thyroid carcinoma

OBJECTIVE

Previous studies did not focus on the differences in the extent of cervical lymph node (LN) dissection according to coexistent Hashimoto's thyroiditis (HT) in patients with papillary thyroid carcinoma (PTC) and its clinical impact. We aimed to determine whether extensive cervical LN dissection is responsible for favourable clinical outcomes in PTC patients with HT and whether the coexistence of HT itself has an independent protective effect regardless of LN status.

DESIGN

Retrospective cohort study.

PATIENTS

1369 patients with PTC who underwent total thyroidectomy with central compartment neck dissection.

MEASUREMENTS

Metastatic LN ratio, defined as number of metastatic LNs divided by number of removed LNs, was used to evaluate the extent of LN dissection as well as the status of LN metastasis. Disease-free survival and dynamic risk stratification were compared for clinical outcomes.

RESULTS

Presence of HT did not lower the risk of cervical LN metastasis (61.6% in patients with HT vs 65.1% in patients without HT, P = .292). Patients with HT had significantly larger numbers of removed LNs than patients without HT (11 vs 8, respectively, P < .001). Accordingly, metastatic LN ratio was smaller in patients with HT (P = .002), which was independently associated with structural persistent/recurrent disease (hazard ratio [HR] 2.33, 95% confidence interval [CI] 1.30-4.16, P = .004). HT itself was negatively associated with structural persistent/recurrent disease after adjustment for other clinicopathological factors (HR 0.39, 95% CI 0.18-0.87, P = .020).

CONCLUSIONS

Coexistence of HT itself is an independent factor associated with favourable outcome in PTC patients, regardless of the extent of LN dissection.

Co-existence of BRAFV600E and TERT promoter mutations in papillary thyroid carcinoma is associated with tumor aggressiveness, but not with lymph node metastasis

BACKGROUND

Mutations of BRAF^V600E and TERT promoters are associated with thyroid cancer development. This study further investigated association of these mutations with clinicopathological characteristics from patients with papillary thyroid carcinoma (PTC).

METHODS

Tumor tissues from 342 PTC patients were obtained for DNA extraction and polymerase chain reaction amplification to detect the BRAF^V600E mutation using amplification-refractory mutation system-polymerase chain reaction. TERT promoter mutations were assessed using Sanger DNA sequencing. The association of these gene mutations with clinicopathological characteristics was then statistically analyzed.

RESULTS

Two hundred and seventy of 342 (78.9%) PTC patients harbored the BRAF^V600E mutation, which was associated with older age male patients. Moreover, TERT promoter mutations occurred in 12 of 342 (3.5 %) PTC patients, all of whom also had the BRAF mutation. One hundred thirty-three patients with papillary thyroid microcarcinoma (PTMC) had no TERT mutations. Statistically, the coexistence of BRAF and TERT promoter mutations were significantly associated with older age, larger tumor size, extrathyroidal extension, and advanced tumor stage, but not with central lymph node metastasis, lateral lymph node metastasis, numbers of lymph node metastasis >5, and numbers of involved/harvested lymph nodes (No. of LNs involved or harvested). The multivariate analyses showed older age (odds ratio [OR], 2.194; 95% CI: 1.117-4.311; p=0.023), larger tumor size (OR, 4.100; 95% CI: 2.257-7.450; p<0.001), and multiplicity (OR, 2.240; 95% CI: 1.309-3.831; p=0.003) were all independent predictors for high prevalence of extrathyroidal extension. However, there was no statistical association with any clinicopathological characteristics except for Hashimoto thyroiditis in PTMC.

CONCLUSION

The current study demonstrated that the coexistence of BRAF and TERT promoter mutations were associated with the PTC aggressiveness, although these mutations were not associated with PTC lymph node metastasis or with PTMC.

Rare Manifestations of Anaplastic Thyroid Carcinoma: the Role of BRAF Mutation Analysis

Anaplastic thyroid carcinoma (ATC) is difficult to distinguish from other cancers, especially when its pathological features are atypical for ATC or when the tumor is totally undifferentiated and occurs after a considerable lapse of time, in an area remote from the original site of the tumor. Here, we present two patients (68-year-old man and 56-year-old woman) with rare manifestations of ATC, which were initially thought to be other malignancies. Immunohistochemical tests, using various markers, failed to provide information about the origin of these tumors. However, both patients had a history of papillary thyroid carcinoma (PTC) from several years ago and BRAF mutations were observed in the undifferentiated tumors, as well as in the previous PTCs. Therefore, we could make a diagnosis of ATC derived from PTC. As such, BRAF mutation analysis may serve as a useful tool for ATC diagnosis in challenging ATC cases.

Association between BRAF V600E Mutation and Ultrasound Features in Papillary Thyroid Carcinoma Patients with and without Hashimoto's Thyroiditis

To assess the association between BRAF V600E mutation and ultrasound (US) features in papillary thyroid carcinoma (PTC) patients with and without Hashimoto’s thyroiditis (HT). We retrospectively reviewed the US features and status of BRAF V600E mutation in 438 consecutive patients with surgically confirmed PTCs. The association between BRAF mutation and US features were analyzed. In addition, we conducted subgroup analyses in terms of coexistent HT. The BRAF mutation was found in 86.5% of patients (379 of 438). Patient age (OR: 1.028, P = 0.010), age ≥ 50 y (OR: 1.904, P = 0.030), and microcalcification (OR: 2.262, P = 0.015) on US were significantly associated with BRAF mutation in PTC patients. Solid component (OR: 5.739, P = 0.019) on US was the significant predictor for BRAF mutation in patients with HT, while age (OR: 1.036, P = 0.017) and microcalcification (OR: 3.093, P = 0.017) were significantly associated with BRAF mutation in patients without HT. In conclusion, older age and microcalcification are risk factors for BRAF mutation in PTC patients, especially in those without HT. For those with HT, however, PTCs with BRAF mutation tend to be solid on ultrasound. These factors might be considered when making treatment planning or prognosis evaluation.

Diagnostic Limitation of Fine-Needle Aspiration (FNA) on Indeterminate Thyroid Nodules Can Be Partially Overcome by Preoperative Molecular Analysis: Assessment of RET/PTC1 Rearrangement in BRAF and RAS Wild-Type Routine Air-Dried FNA Specimens

Molecular markers are helpful diagnostic tools, particularly for cytologically indeterminate thyroid nodules. Preoperative RET/PTC1 rearrangement analysis in BRAF and RAS wild-type indeterminate thyroid nodules would permit the formulation of an unambiguous surgical plan. Cycle threshold values according to the cell count for detection of the RET/PTC1 rearrangement by real-time reverse transcription-polymerase chain reaction (RT-PCR) using fresh and routine air-dried TPC1 cells were evaluated. The correlation of RET/PTC1 rearrangement between fine-needle aspiration (FNA) and paired formalin-fixed paraffin-embedded (FFPE) specimens was analyzed. RET/PTC1 rearrangements of 76 resected BRAF and RAS wild-type classical PTCs were also analyzed. Results of RT-PCR and the Nanostring were compared. When 100 fresh and air-dried TPC1 cells were used, expression of RET/PTC1 rearrangement was detectable after 35 and 33 PCR cycles, respectively. The results of RET/PTC1 rearrangement in 10 FNA and paired FFPE papillary thyroid carcinoma (PTC) specimens showed complete correlation. Twenty-nine (38.2%) of 76 BRAF and RAS wild-type classical PTCs had RET/PTC1 rearrangement. Comparison of RET/PTC1 rearrangement analysis between RT-PCR and the Nanostring showed moderate agreement with a κ value of 0.56 (p = 0.002). The RET/PTC1 rearrangement analysis by RT-PCR using routine air-dried FNA specimen was confirmed to be technically applicable. A significant proportion (38.2%) of the BRAF and RAS wild-type PTCs harbored RET/PTC1 rearrangements.

Programmed Death-Ligand 1 Expression in Papillary Thyroid Cancer and Its Correlation with Clinicopathologic Factors and Recurrence

BACKGROUND

Programmed death-ligand 1 (PD-L1) expression has been reported in several malignancies, but the expression of PD-L1 in papillary thyroid cancer (PTC) has been characterized rarely. The aim of this study was to assess the significance of PD-L1 expression and its associations with clinicopathologic factors and disease outcome in PTC.

METHODS

Immunohistochemistry staining was conducted retrospectively to evaluate the expression of PD-L1 in a total of 260 PTC tumors and corresponding non-tumor tissues. The correlations between PD-L1 expressions with clinicopathologic features and recurrence-free survival (RFS) were analyzed.

RESULTS

PD-L1 expression was positive in 52.3% (136/260) of PTC tumor tissues, which was significantly higher than in corresponding non-tumor thyroid tissues. In clinicopathologic analyses, this positive staining of PD-L1 was positively linked to multifocality (p = 0.001) and extrathyroidal extension (p = 0.001). In multivariate Cox regression analysis, positive PD-L1 expression in tumor tissue was significantly associated with worse RFS (hazard ratio 2.825 [confidence interval 1.149-6.943], p = 0.024). In subgroup analyses based on clinicopathologic factors, positive PD-L1 staining of tumor tissue was associated with worse RFS in males (p = 0.001), older patients (≥45 years; p = 0.001), and patients with a primary tumor size >4 cm (p = 0.002), multifocal tumors (p = 0.031), extrathyroidal extension (p = 0.012), and lymph node metastasis (p = 0.004). In contrast, positive PD-L1 staining predicted worse RFS in the subgroup of patients without Hashimoto's thyroiditis (p = 0.001) and treated with total thyroidectomy (p = 0.019).

CONCLUSIONS

PD-L1 is important in determining aggressiveness of PTC and could predict the prognosis of patients. Therefore, inhibition of PD-L1 is suggested as a potential strategy for the treatment of advanced PTC with high expression of PD-L1.

Association between BRAFV600E mutation and the clinicopathological features of solitary papillary thyroid microcarcinoma

The B-Raf proto-oncogene serine/threonine kinase (BRAF)^V600E mutation is an important oncogene in the development of papillary thyroid carcinoma (PTC) and has been identified as a risk factor for poor prognosis in patients with PTC. However, whether the BRAF^V600E mutation is a prognostic marker in patients with solitary papillary thyroid microcarcinoma (sPTMC) has not yet been established. The present study aimed to identify the association between BRAF^V600E mutation and the clinicopathological features of patients with sPTMC. A total of 108 patients with sPTMC who underwent surgery at the Cancer Institute and Hospital of the Chinese Academy of Medical Sciences between December 2010 and December 2012 were analyzed retrospectively. Exon 15 of the BRAF gene was amplified using the polymerase chain reaction and direct sequencing was performed to detect the BRAF^V600E mutation. Statistical analysis was subsequently performed using SPSS software (version 16.0). The association between BRAF^V600E mutation and clinicopathological features of sPTMC was tested with the χ² test or Fisher's exact test, as appropriate. There were 27 males and 81 females in the cohort, who were aged between 22 and 66 years old, with an average age of 42 years. The BRAF^V600E mutation was found in 59 out of 108 (54.6%) patients with sPTMC. The presence of the BRAF^V600E mutation was demonstrated to be significantly associated with extrathyroidal extension (P=0.019), advanced Tumor-Node-Metastasis stage (P=0.007) and the presence of autoimmune thyroiditis (P=0.010). The BRAF^V600E mutation was not significantly associated with gender, anatomic location or subtype of sPTMC (P>0.05). In addition, the BRAF^V600E mutation indicated poor prognosis in patients with sPTMC. These results suggest that the BRAF^V600E mutation is a risk factor for poor prognosis in patients with sPTMC. This knowledge will aid in the risk stratification and post-operative management of patients with sPTMC.

The micropapillary/hobnail variant of papillary thyroid carcinoma: A review of series described in the literature compared to a series from one southern Italy pathology institution

Papillary thyroid carcinoma (PTC) has a good prognosis with a 10-yr survival greater than 90%. Recently, a micro-papillary pattern with hobnail appearance (MPHC) in PTC has been indicated as associated with poor prognosis, but this suggestion is based only on a few cases from geographical areas different from ours. Two-hundred ninety-nine consecutive PTC cases were collected between the years of 1992 and 2014 at our institution. The corresponding histologic sections (at least 6 for each case) were stained with hematoxylin and eosin and reviewed independently by two pathologists to reach a consensus on the identification and quantification of the MPHC. As done in other cohorts, parallel serial sections were stained with antisera for thyroglobulin, epithelial membrane antigen, thyroid-transcription-factor-1 and Ki 67. BRAF gene mutation at codon 600 and RET/PTC1 gene rearrangements were searched. A comparative statistical analysis was done between the present series and previously published series. Of the 295 PTC, 124 (42.5%) were follicular, 104 (35%) classic, 34 (11.5%) sclerosing, 15 (5%) tall cells, 10 (3.4%) Warthin-like, and 8 (2.7%) MPHC. Four MHPC cases (50%) harbored the BRAF V600E variant, while one was positive for RET/PTC1 rearrangement. Our rate of MPHC-PTC (2.7%) is 2X to 8X greater than those reported previously for cohorts from North America + North Italy, Korea and Mexico. MPHC prognosis appears to be better compared to other cohorts, probably due to not only to the lower rate of the vascular invasion, but also to the smaller size of the MPHC-PTC nodule.

BRAF and Epithelial-Mesenchymal Transition: Lessons From Papillary Thyroid Carcinoma and Primary Cutaneous Melanoma

The increased prevalence of BRAF mutations in thyroid carcinoma and primary cutaneous melanoma (PCM) hint that dysregulation of BRAF might contribute to the noted association between PCM and thyroid carcinoma. A recent study evaluating the rate of BRAFV600E mutations among patients who had been diagnosed with primary papillary thyroid carcinoma (PTC) and PCM showed that patients with either PCM or PTC were at an increased risk of developing the other as a second primary malignant neoplasm. Furthermore, the authors noted that samples from patients suffering from both malignancies exhibited a higher rate of incidence of the BRAFV600E mutation, compared with patients not suffering from both malignancies. These studies support the hypothesis that the pathogenesis of these 2 malignancies might share a conserved molecular pattern associated with dysregulation of the BRAF protein. One mechanism through which BRAF might contribute to PCM and thyroid carcinoma progression is through induction of epithelial-mesenchymal transition (EMT). Specifically, the Snail/E-cadherin axis has been demonstrated as a pathway dysregulated by BRAF, leading to EMT in both malignancies. Our analysis focuses on the results of these recent investigations, and through a review of select molecules relevant to EMT, looks to provide a context by which to better understand the relevance and role of stromal-parenchymal signaling and the BRAF mutation in the pathogenesis of PTC and PCM.

Discriminatory value of carotid artery elasticity changes for the evaluation of thyroid dysfunction in patients with hashimoto's thyroiditis

PURPOSE

To evaluate the discriminatory value of carotid artery wall thickness and elasticity for thyroid dysfunction in Hashimoto's thyroiditis (HT) patients.

METHODS

A total of 180 female HT patients were assigned to three groups on the basis of laboratory testing: HT hyperthyroidism group (group A), HT hypothyroidism group (group B), and HT euthyroid group (group C). We used radiofrequency sonographic signal analysis for the measurement of intima-media thickness and arterial stiffness.

RESULTS

Intima-media thickness was significantly higher in group A than in other groups. After stepwise variable selection, distensibility coefficient (DC), compliance coefficient, stiffness index (β), and pulse wave velocity (PWV) were selected to discriminate different thyroid hormone levels, resulting in the following discriminant function: Z1 = -0.398DC + 0.803PWV. The receiver-operator characteristic curve analysis showed that the critical points were DC = 0.022 kPa(-1) and PWV = 5.36 m/s for HT hyperthyroidism, and DC = 0.016 kPa(-1) and PWV = 6.875 m/s for HT hypothyroidism.

CONCLUSIONS

DC and PWV may be useful for the evaluation of thyroid function in HT patients. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:298-304, 2016.

Increase in Papillary Thyroid Cancer Incidence Is Accompanied by Changes in the Frequency of the BRAF V600E Mutation: A Single-Institution Study

BACKGROUND

Thyroid cancer (TC) has one of the fastest increasing incidences worldwide and primarily involves papillary thyroid cancer (PTC). The BRAF(V600E) mutation is the most common genetic alteration identified in PTC. There are few data concerning an association between the rising incidence of PTC and the increasing prevalence of BRAF-positive cases. Environmental factors such as iodine intake may be responsible for the changing molecular features of PTC. The aim of this study was to evaluate probable variations in the frequency of the BRAF(V600E) mutation in PTC that were diagnosed at a single institution over 14 years in Poland, a country with a demonstrated improvement in iodine supplementation in the early 21st century.

METHODS

Time-dependent trends in the prevalence of the BRAF(V600E) mutation during three time periods (2000-2004, 2005-2009, and 2010-2013) were analyzed. The BRAF mutation was genotyped using direct sequencing, allele-specific polymerase chain reaction (PCR), and real-time PCR in 723 unselected cases of PTC that were diagnosed in 2000-2013. Trends in the clinicopathologic characteristics of all PTCs and BRAF(V600E)-positive PTCs were also analyzed.

RESULTS

The proportion of PTCs with mutations significantly increased over the study period (54.8% vs. 70.6%; p = 0.001). The median tumor size of all and BRAF-positive tumors decreased (p = 0.008 and p = 0.001, respectively) and correlated with an increase in the proportion of all and mutated microcarcinomas (p = 0.003 and p = 0.003, respectively). A decrease in all and mutated tumors between 2 and 4 cm was also observed (p = 0.002 and p = 0.006, respectively). A significant decrease in tumors ≥ 4 cm in size was only observed in BRAF-positive cases (p = 0.017). The proportion of classic PTC with BRAF(V600E) mutation was observed to increase (57.6% vs. 74.4%; p = 0.001) and was stable for the follicular variant of PTC (p = 0.336).

CONCLUSIONS

The prevalence of the BRAF(V600E)mutation increased significantly in PTCs diagnosed in the authors' institution. Improved detection and several causative factors, most likely environmental and changes in iodine intake, may contribute to the increasing occurrence of TC.

Comparison of Clinical and Ultrasonographic Features of Poorly Differentiated Thyroid Carcinoma and Papillary Thyroid Carcinoma

Background:

The clinical behavior and management of poorly differentiated thyroid carcinoma (PDTC) are very different from papillary thyroid carcinoma (PTC). By comparing the clinical and ultrasonographic features between the two tumors, we proposed to provide more possibilities for recognizing PDTC before treatment.

Methods:

The data of 13 PDTCs and 39 age- and gender-matched PTCs in Peking Union Medical College Hospital between December 2003 and September 2013 were retrospectively reviewed. The clinical and ultrasonic features between the two groups were compared.

Results:

The frequencies of family history of carcinoma, complication with other thyroid lesions, lymph node metastases, recurrent laryngeal nerve injuries, and distant metastases were higher in PDTCs (30.8%, 61.6%, 69.2%, 23.1%, and 46.2%, respectively) than those in PTCs (2.6%, 23.1%, 25.6%, 2.6%, and 2.6%, respectively) (P < 0.05). The mortality rate of PDTCs was greatly higher than PTCs (P < 0.01). Conventional ultrasound showed that the size of PDTCs was larger than that of PTCs (3.1 ± 1.9 cm vs. 1.7 ± 1.0 cm). Clear margins and rich and/or irregular blood flow were found in 92.3% of PDTCs, which differed substantially from PTCs (51.7% and 53.8%, respectively) (P < 0.05).

Conclusions:

PDTC is more aggressive and its mortality rate is higher than PTCs. Accordingly, more attention should be given to suspicious thyroid cancer nodules that show large size, regular shape, and rich blood flow signals on ultrasound to exclude the possibility of PDTCs.

Chronic lymphocytic thyroiditis and BRAF V600E in papillary thyroid carcinoma

It has been reported that papillary thyroid carcinoma (PTC) with chronic lymphocytic thyroiditis (CLT) is less associated with extrathyroidal extension (ETE), advanced tumor stage and lymph node (LN) metastasis. Other studies have suggested that concurrent CLT could antagonize PTC progression, even in BRAF-positive patients. Since the clinical significance of the BRAF mutation has been particularly associated with conventional PTC, the purpose of this study was to determine the clinical significance of CLT according to BRAF mutation status in conventional PTC patients. We retrospectively reviewed the medical records of 3332 conventional PTC patients who underwent total thyroidectomy with bilateral central neck dissection at the Thyroid Cancer Center of Samsung Medical Center between January 2008 and June 2015. In this study, the prevalence of BRAF mutation was significantly less frequent in conventional PTC patients with CLT (76.9% vs 86.6%). CLT was an independent predictor for low prevalence of ETE in both BRAF-negative (OR=0.662, P=0.023) and BRAF-positive (OR=0.817, P=0.027) conventional PTC patients. In addition, CLT was an independent predictor for low prevalence of CLNM in both BRAF-negative (OR=0.675, P=0.044) and BRAF-positive (OR=0.817, P=0.030) conventional PTC patients. In conclusion, BRAF mutation was significantly less frequent in conventional PTC patients with CLT. However, CLT was an independent predictor for less aggressiveness in conventional PTC patients regardless of BRAF mutation status.

The impact of coexistent Hashimoto's thyroiditis on lymph node metastasis and prognosis in papillary thyroid microcarcinoma

The impact of coexistent Hashimoto's thyroiditis (HT) on lymph node metastasis (LNM) and prognosis in papillary thyroid microcarcinoma (PTMC) remains controversial. We evaluated the association of coexistent HT with clinicopathologic parameters, LNM, and prognosis by retrospectively reviewing a series of consecutive patients treated for PTMC at Fudan University Cancer Center from January 2005 to December 2010. Of all 1,250 patients with complete data for analysis, 364 (29.1 %) had coexistent HT (HT group) and 886 patients (70.9 %) had no evidence of HT (control group). The HT group had higher proportion of female (87.9 vs 70.1 %) patients, higher mean level of thyroid-stimulating hormone (TSH) (2.39 vs 2.00 mIU/L), and lower incidence of extrathyroidal extension (7.4 vs 11.7 %) than those in the control group. However, the incidence of LNM and recurrence was similar between the two groups, and HT was not associated with LNM and recurrence. A series of clinicopathologic factors identified for predicting LNM and recurrence in the control group did not show any prediction in the HT group. In summary, this study suggested that coexistent HT had insignificant protective effect on LNM and prognosis in PTMC, which was inconsistent with prior studies. Further studies aiming to determine novel predictors are recommended in PTMC patients with coexistent HT.

Mutation Profile of Well-Differentiated Thyroid Cancer in Asians

Recent advances in molecular diagnostics have led to significant insights into the genetic basis of thyroid tumorigenesis. Among the mutations commonly seen in thyroid cancers, the vast majority are associated with the mitogen-activated protein kinase pathway. B-Raf proto-oncogene (BRAF) mutations are the most common mutations observed in papillary thyroid cancers (PTCs), followed by RET/PTC rearrangements and RAS mutations, while follicular thyroid cancers are more likely to harbor RAS mutations or PAX8/peroxisome proliferator-activated receptor γ (PPARγ) rearrangements. Beyond these more common mutations, alterations in the telomerase reverse transcriptase (TERT) promoter have recently been associated with clinicopathologic features, disease prognosis, and tumorigenesis in thyroid cancer. While the mutations underlying thyroid tumorigenesis are well known, the frequency of these mutations is strongly associated with geography, with clear differences reported between Asian and Western countries. Of particular interest is the prevalence of BRAF mutations, with Korean patients exhibiting the highest rate of BRAF-associated thyroid cancers in the world. Here, we review the prevalence of each of the most common mutations in Asian and Western countries, and identify the characteristics of well-differentiated thyroid cancer in Asians.

Potential relationship between Hashimoto's thyroiditis and BRAF(V600E) mutation status in papillary thyroid cancer

BACKGROUND

The purpose of this study was to evaluate the potential relationship between Hashimoto's thyroiditis and BRAF(V600E) mutation status in patients with papillary thyroid carcinoma (PTC).

METHODS

A total of 619 patients with PTC who underwent total thyroidectomy with lymph node dissection were enrolled in this study. Univariable and multivariate analyses were used.

RESULTS

Hashimoto's thyroiditis was present in 35.9% (222 of 619) of PTCs. Multivariate logistic regressions showed that BRAF(V600E) mutation, sex, extrathyroidal extension, and lymph node metastasis were independent factors for Hashimoto's thyroiditis. Female sex, more frequent extrathyroidal extension, and a higher incidence of lymph node metastasis were significantly associated with PTCs accompanied by BRAF(V600E) mutation without Hashimoto's thyroiditis compared with PTCs accompanied by BRAF(V600E) mutation with Hashimoto's thyroiditis.

CONCLUSION

Hashimoto's thyroiditis was negatively associated with BRAF(V600E) mutation, extrathyroidal extension, and lymph node metastasis. In addition, Hashimoto's thyroiditis was related to less lymph node metastasis and extrathyroidal extension in PTCs with BRAF(V600E) mutation. Therefore, Hashimoto's thyroiditis is a potentially protective factor in PTC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1019-E1025, 2016.

Combined effect of Hashimoto's thyroiditis and BRAF(V600E) mutation status on aggressiveness in papillary thyroid cancer

BACKGROUND

The purpose of this study was to evaluate the association between Hashimoto's thyroiditis and BRAF(V600E) mutation status in patients with papillary thyroid cancer (PTC) and to determine their combined association with tumor aggressiveness in PTC.

METHODS

A total of 1780 patients with PTC who underwent surgery were enrolled in this study. Simple and multiple analyses were performed to determine the association between Hashimoto's thyroiditis and the BRAF(V600E) mutation in PTC.

RESULTS

Hashimoto's thyroiditis was present in 11.5% of patients (204/1780) with PTC. Multiple logistic regressions showed that BRAF(V600E) (odds ratio [OR] = 0.493; 95% confidence interval [CI] = 0.360-0.678) and the female sex (OR = 7.146; 95% CI = 3.408-18.347) were independent factors associated with Hashimoto's thyroiditis in PTC. BRAF(V600E) mutation and the Hashimoto's thyroiditis-negative PTC group were associated with aggressive disease (OR = 3.069; 95% CI = 1.654-5.916).

CONCLUSION

Hashimoto's thyroiditis was associated less frequently with BRAF(V600E) , and frequently with the female sex in patients with PTC. Hashimoto's thyroiditis and BRAF(V600E) status may help to predict clinical outcome of PTC.

Clinical significance of BRAF V600E mutation in 154 patients with thyroid nodules

The aim of the present study was to investigate the prevalence of the BRAF V600E mutation in papillary thyroid carcinoma (PTC) patients from eastern coastal China and to determine whether it is correlated with the clinicopathological features of PTCs with or without current Hashimoto thyroiditis (HT). The BRAF V600E mutation status was analyzed in 206 thyroid nodules of 154 patients undergoing thyroidectomy using polymerase chain reaction and bi-directional sequencing. Multivariate analysis was performed to investigate the association of the BRAF V600E mutation with clinicopathological features. Thyroid nodules were classified as PTC, nodular goiter (NG), adenomatoid nodule, adenoma and HT. The BRAF V600E mutation was observed in 61.5% of PTCs analyzed; it was also detected in one normal tissue adjacent to PTC and one NG. One patient exhibited double mutations in the BRAF gene; the BRAF V600E mutation in the PTC lesion and the BRAF K601E mutation in the contralateral NG lesion. Patients harboring the BRAF V600E mutation had higher thyroid stimulating hormone levels (2.453±1.464 vs. 1.966±1.296 mIU/l), a reduced occurrence of papillary thyroid microcarcinoma (55.0 vs. 88%), and a higher occurrence of lymph node metastasis (LNM; 42.5 vs. 16.0%) compared with those with wild-type BRAF (all P<0.05). Binary logistic regression analysis revealed that the BRAF V600E mutation was associated with LNM of PTC (hazard ratio, 5.051; 95% confidence interval, 1.068-23.893; P=0.041). Conversely, no association was identified between the BRAF V600E mutation and HT (38.5 vs. 67.3%, χ2=3.656, P=0.056). Thus, in regional PTCs, the BRAF V600E mutation was prevalent, suggesting that it may be an early and phenotypically defining molecular event in PTC, and may represent an independent factor that predicts LNM.

Thyroid nodules: pathophysiological insight on oncogenesis and novel diagnostic techniques

Thyroid nodules are a very frequent pathology among common population. Despite the vast majority of them are of benign origin, the incidence of thyroid cancer is currently rather rising. Although there are several risk factors of thyroid cancer and several clinical, ultrasound, biochemical and molecular diagnostic markers, the exact mechanisms of thyroid oncogenesis and the linkage between thyroid nodule ultrasound appearance and its biological character remain unclear. While ionizing radiation is the only one well-known risk factor for thyroid cancer, the significance of some others remains unclear. The aim of our review was to discuss some not completely known pathophysiological mechanisms involved in thyroid oncogenesis as hypothyroidism, mutations of genes regulating cell proliferation, thyroid autoimmunity and pregnancy and to describe pathophysiological background of some ultrasound markers of thyroid cancer (size, echogenicity, vascularization, calcifications and stiffness). Better knowledge in this field is crucial for development of novel diagnostic techniques and therapeutic approaches. For example, the analysis of BRAF, RAS and other mutations in cytological samples may help to distinction between follicular thyroid carcinoma and follicular thyroid adenoma and may significantly decrease the number of unnecessary surgery among patients with thyroid nodules. Alternatively, the different malign cells growth, angiogenesis, destructions of thyroid follicles, reparative changes, growth retardation, fibrosis and increased interstitial fluid pressure implicate the typical ultrasound appearance of papillary thyroid cancer (hypoechogenicity, irregular vascularization, microcalcifications, stiffness) which is essential to catch the suspicious nodules on the basis of their ultrasound appearance among large amount of benign nodules.

The Warthin-Like Variant of Papillary Thyroid Carcinoma: A Comparison with Classic Type in the Patients with Coexisting Hashimoto's Thyroiditis

Background. The Warthin-like variant of papillary thyroid (WLPTC) is a rare subtype of papillary thyroid carcinoma (PTC) resembling Warthin tumors of the salivary glands. Due to its rarity, the clinicopathologic and molecular features of WLPTC remain unclear. Methods. Of the 2,139 patients who underwent surgical treatment for PTC from 2012 to 2013, 40 patients with WLPTC were identified and compared to 200 consecutive patients with classic PTC. BRAF mutation was tested with pyrosequencing. Results. There were no significant differences in age, predilection for women, multifocality, extrathyroidal extension, or lymph node metastasis between WLPTC and classic PTC. However, WLPTCs were more commonly associated with Hashimoto's thyroiditis than classic PTCs (93% versus 36%, resp., P < 0.001) and showed significantly lower rate of BRAF mutation when compared to classic PTCs (65% versus 84%, resp., P = 0.007). In classic PTC, the frequency of BRAF mutations was negatively correlated with coexisting Hashimoto's thyroiditis. When we compared WLPTC and classic PTC in the patients with coexisting Hashimoto's thyroiditis, there were no significant differences in clinicopathologic characteristics or the BRAF mutational rate between the two groups. Conclusions. Patients with WLPTC have similar demographic, clinical, pathologic, and molecular characteristics to those with classic PTC coexisting with Hashimoto's thyroiditis.

BRAF mutation correlates with recurrent papillary thyroid carcinoma in Chinese patients

PURPOSE

We investigated correlations of somatic BRAF V600E mutation and RET/PTC1 rearrangement with recurrent disease in Chinese patients with papillary thyroid carcinoma (ptc).

METHODS

This prospective study included 214 patients with ptc histologically confirmed between November 2009 and May 2011 at a single institute.

RESULTS

We found somatic BRAF V600E mutation in 68.7% and RET/PTC1 rearrangement in 25.7% of the patients. Although BRAF mutation was not significantly associated with clinicopathologic features such as patient sex or age, multicentric disease, thyroid capsule invasion, tumour stage, or nodal metastasis, it was significantly associated with recurrent disease. Multivariate analysis revealed that BRAF mutation and tumour size were independent risk factors associated with recurrent disease, with odds ratios of 9.072 and 2.387 respectively. The area under the receiver operating characteristic curve increased 8.3% when BRAF mutation was added to the traditional prognostic factors, but that effect was statistically nonsignificant (0.663 vs. 0.746, p = 0.124). RET/PTC1 rearrangement and nodal metastasis were significantly associated in all patients (p = 0.042), marginally associated in ptc patients (p = 0.051), but not associated in microptc patients (p = 0.700). RET/PTC1 rearrangement was not significantly associated with recurrent disease.

CONCLUSIONS

BRAF positivity is an independent predictor of recurrent disease in ptc.

Does papillary thyroid carcinoma have a better prognosis with or without Hashimoto thyroiditis?

BACKGROUND

It has been reported that the BRAF (V600E) mutation is related to a low frequency of background Hashimoto thyroiditis (HT); however, there are not many factors known to be related to the development of HT. The aim of this study was to determine whether patients with both papillary thyroid carcinoma (PTC) and HT show aggressive features, by investigating the clinicopathological features of HT in patients with PTC.

METHODS

A database of patients with PTC who underwent thyroidectomy between October 2008 and August 2012 was collected and reviewed. All 2464 patients were offered a thyroidectomy, and DNA was extracted from the atypical cells in the surgical specimens for detection of the BRAF (V600E) mutation. Clinical and pathological characteristics were also investigated.

RESULTS

Four hundred and fifty-two of 1945 (23.2%) patients were diagnosed with HT, and of these, 119 (72.1%) had a BRAF (V600E) mutation. HT was not significantly associated with the BRAF (V600E) mutation (P < 0.001) and extrathyroidal extensions (P = 0.005) but was associated with a low stage (P = 0.011) and female predominance (P < 0.001). In a subgroup analysis for gender, HT was associated with a low probability of BRAF (V600E) mutations in both genders (P < 0.001 for both females and males). Also, recurrence was significantly associated with HT (OR 0.297, CI 0.099-0.890, P = 0.030), lymph node ratio (OR 2.545, CI 1.092-5.931, P = 0.030), and BRAF (V600E) mutation (OR 2.075, CI 1.021-4.217, P = 0.044). However, there was no relationship with clinicopathological factors or with death.

CONCLUSIONS

Our results show that HT in patients with PTC is associated with a low probability of BRAF (V600E) mutations. Moreover, HT was correlated with some factors that were associated with less aggressive clinical features and inversely related to recurrence. Therefore, these results may be useful to predict whether PTC concurrent with HT exhibits a better prognosis than PTC alone.

Study of the histological profile of papillary thyroid carcinomas associated with Hashimoto's thyroiditis

OBJECTIVE

To investigate the association between the histological parameters of papillary thyroid cancer (PTC) and the presence of Hashimoto's thyroiditis (HT).

MATERIALS AND METHODS

Histological samples from patients with PTC were reviewed by an endocrine pathologist. The following parameters were analyzed: presence of concomitant HT, multifocality, presence of nodal metastasis, tumor size, vascular invasion, perineural infiltration, histological variant, and pathological staging. Clinical data included gender and age at the time of the diagnosis.

RESULTS

A total of 94 cases of PTC were reviewed. There was a predominance of women (85.1% vs. 14.9%) and median age at presentation was 45.13 years. The presence of HT was significantly associated with greater occurrence of multifocal tumors (p = 0.004), early pathological stage (p = 0.02), and smaller tumor size (p = 0.025).

CONCLUSIONS

Patients with PTC associated with HT had significantly smaller tumors, more often multifocal and in an earlier stage than their counterparts without HT. A better understanding of the immune response involved in these tumors may be useful for future strategies on the prevention and for the development of new therapeutic approaches for this group of neoplasms.

Additional BRAF mutation analysis may have additional diagnostic value in thyroid nodules with "suspicious for malignant" cytology alone even when the nodules do not show suspicious US features

The BRAF(V600E) mutation test has been more effective in thyroid nodules with suspicious US features than ones without suspicious features. Therefore, we investigated the role of the BRAF(V600E) mutation as an additional study to cytology in diagnosing a thyroid nodule without suspicious US features. This study was performed at Severance hospital from December 2010 through February 2012. During this period, 2,650 patients with 2,918 nodules underwent FNA with an additional BRAF(V600E) mutation test. Among them, we excluded thyroid nodules with suspicious US features. Finally, 485 thyroid nodules in 466 patients (mean age 50.3 years; range 9-80 years) were included in this study. We compared the differences between patients with malignant and benign thyroid nodules. We evaluated the detection rates of the BRAF(V600E) mutation according to the Bethesda System for Reporting Thyroid Cytopathology (BSRTC). There were 60 (60/485, 12.4 %) malignant and 425 (425/485, 87.6 %) benign nodules. The detection rate of the BRAF(V600E) mutation in thyroid nodules without suspicious US features was only 6.6 % (32/485). Most had malignant cytology (62.5 %, 20/32). For nodules without malignant cytology, only 12 nodules (2.6 %, 12/462) had the BRAF mutation. Among the 12 nodules, nine nodules were suspicious for malignancy on cytology. Additional BRAF mutation analysis shows additional diagnostic value in thyroid nodules with "suspicious for malignant" cytology alone even when the nodules do not show suspicious US features. Therefore, the test should be selectively performed in thyroid nodules without suspicious US features, considering cost-effectiveness as well as diagnostic accuracy.

RNA sequencing identifies multiple fusion transcripts, differentially expressed genes, and reduced expression of immune function genes in BRAF (V600E) mutant vs BRAF wild-type papillary thyroid carcinoma

CONTEXT

The BRAF V600E mutation (BRAF-MUT) confers an aggressive phenotype in papillary thyroid carcinoma, but unidentified additional genomic abnormalities may be required for full phenotypic expression.

OBJECTIVE

RNA sequencing (RNA-Seq) was performed to identify genes differentially expressed between BRAF-MUT and BRAF wild-type (BRAF-WT) tumors and to correlate changes to patient clinical status.

DESIGN

BRAF-MUT and BRAF-WT tumors were identified in patients with T1N0 and T2-3N1 tumors evaluated in a referral medical center. Gene expression levels were determined (RNA-Seq) and fusion transcripts were detected. Multiplexed capture/detection and digital counting of mRNA transcripts (nCounter, NanoString Technologies) validated RNA-Seq data for immune system-related genes.

PATIENTS

BRAF-MUT patients included nine women, three men; nine were TNM stage I and three were stage III. Three (25%) had tumor infiltrating lymphocytes. BRAF-WT included five women, three men; all were stage I, and five (62.5%) had tumor infiltrating lymphocytes.

RESULTS

RNA-Seq identified 560 of 13 085 genes differentially expressed between BRAF-MUT and BRAF-WT tumors. Approximately 10% of these genes were related to MetaCore immune function pathways; 51 were underexpressed in BRAF-MUT tumors, whereas 4 (HLAG, CXCL14, TIMP1, IL1RAP) were overexpressed. The four most differentially overexpressed immune genes in BRAF-WT tumors (IL1B; CCL19; CCL21; CXCR4) correlated with lymphocyte infiltration. nCounter confirmed the RNA-Seq expression level data. Eleven different high-confidence fusion transcripts were detected (four interchromosomal; seven intrachromosomal) in 13 of 20 tumors. All in-frame fusions were validated by RT-PCR.

CONCLUSION

BRAF-MUT papillary thyroid cancers have reduced expression of immune/inflammatory response genes compared with BRAF-WT tumors and correlate with lymphocyte infiltration. In contrast, HLA-G and CXCL14 are overexpressed in BRAF-MUT tumors. Sixty-five percent of tumors had between one and three fusion transcripts. Functional studies will be required to determine the potential role of these newly identified genomic abnormalities in contributing to the aggressiveness of BRAF-MUT and BRAF-WT tumors.