Clinicopathologic correlations of the BRAFV600E mutation, BRAF V600E immunohistochemistry, and BRAF RNA in situ hybridization in papillary thyroid carcinoma

Deciphering the Role of BRAFV600E Immunohistochemistry in Breast Lesions: A Comprehensive Review

The BRAFV600E mutation has been extensively studied in various cancers, but its role in breast lesions remains less understood. Immunohistochemistry (IHC) has emerged as a valuable tool for detecting BRAFV600E expression in breast tissue, aiding in diagnosis and prognosis. This comprehensive review examines the significance of BRAFV600E IHC in breast lesions, encompassing its frequency, association with clinicopathological features, and potential clinical implications. We summarize key findings, emphasizing their utility in diagnosis, prognosis prediction, and treatment response assessment. Additionally, we discuss implications for clinical practice, highlighting the need for integrating BRAFV600E IHC into diagnostic algorithms. Recommendations for future research include larger-scale studies to validate findings, optimize detection techniques, and explore therapeutic interventions targeting BRAFV600E in breast cancer. This review contributes to understanding the molecular landscape of breast lesions and informs clinical decision-making in their management.

Expression data of FOS and JUN genes and FTIR spectra provide diagnosis of thyroid carcinoma

We explore the feasibility of using FOS and JUN gene expression and ATR-FTIR for diagnosis of thyroid cancer. For the study, 38 samples (6 non-neoplastic (NN), 10 papillary thyroid carcinoma (PTC), 7 follicular thyroid carcinoma (FTC), and 15 benign tumors (BT) were subjected to RNA extraction followed by quantitative real time PCR (qRT-PCR) and 30 samples (5 NN, 9 PTC, 5 FTC, and 11 BT) were used for Attenuated Total Reflectance - Fourier Transform Infrared (ATR-FTIR) followed by multivariate analysis. Of the above, 20 samples were used for both gene expression and ATR-FTIR studies. We found FOS and JUN expression in malignant tumor samples to be significantly lower than NN and benign. ATR-FIR after multivariate analysis could identify the difficult to diagnose FTC with 93 % efficiency. Overall, results suggest the diagnostic potential of molecular biology techniques combined with ATR-FTIR spectroscopy in differentiated thyroid carcinomas (PTC and FTC) and BT.

The Prognostic Significance of BRAF Gene Analysis in Children and Adolescents with Papillary Thyroid Carcinoma: A Systematic Review and Meta-Analysis

Thyroid cancer represents the prominent endocrine cancer in children. Papillary thyroid cancer (PTC) constitutes its most frequent (>90%) pediatric histological type. Mutations energizing the mitogen-activated-protein kinase (MAPK) pathway are definitely related to PTC. Its most common genetic alteration is in proto-oncogene B-Raf (BRAF). Mutated BRAF is proposed as a prognostic tool in adult PTC. We conducted a systematic review and meta-analysis evaluating the association of mutated BRAF gene and prognostic clinicopathological characteristics of PTC in children/adolescents. Systematic search for relevant studies included PubMed, MEDLINE, Scopus, clinicaltrials.gov and Cochrane Library. Pooled estimates of odds ratios for categorical data and mean difference for continuous outcomes were calculated using random/fixed-effect meta-analytic models. BRAFV600E mutation presents a pooled pediatric/adolescent prevalence of 33.12%. Distant metastasis is significantly associated with mutated BRAF gene (OR = 0.32, 95% CI = 0.16-0.61, p = 0.001). Tumor size (MD = -0.24, 95% CI = -0.62-0.135, p = 0.21), multifocality (OR = 1.13, 95% CI = 0.65-2.34, p = 0.74), vascular invasion (OR = 1.17, 95% CI = 0.67-2.05, p = 0.57), lymph node metastasis (OR = 0.92, 95% CI = 0.63-1.33, p = 0.66), extra-thyroid extension (OR = 0.78, 95% CI = 0.53-1.13, p = 0.19) and tumor recurrence (OR = 1.66, 95% CI = 0.68-4.21, p = 0.376) presented no association or risk with BRAF mutation among pediatric/adolescent PTC. Mutated BRAF gene in children and adolescents is less common than in adults. Mutation in BRAF relates significantly to distant metastasis among children/adolescents with PTC.

BRAF V600E Mutation in Ameloblastoma: A Systematic Review and Meta-Analysis

The discovery that ameloblastoma has a high mutation incidence of BRAF V600E may enable a better investigation of pathophysiology. However, there is inconsistent evidence regarding this mutation occurrence and its association with clinical information. This systematic review and meta-analysis aim to pool the overall mutation prevalence of BRAF V600E in reported ameloblastoma cases and to determine its association with patient demographic and clinicopathological features. Following the PRISMA guidelines, a comprehensive article search was conducted through four databases (Scopus, Google Scholar, PubMed, and Web of Science). Seventeen articles between 2014 and 2022 met the inclusion criteria with 833 ameloblastoma cases. For each included study, the significance of BRAF V600E on the outcome parameters was determined using odd ratios and 95% confidence intervals. Meta-analysis prevalence of BRAF V600E in ameloblastoma was 70.49%, and a significant meta-analysis association was reported for those younger than 54 years old and in the mandible. On the contrary, other factors, such as sex, histological variants, and recurrence, were insignificant. As a result of the significant outcome of BRAF V600E mutation in ameloblastoma pathogenesis, targeted therapy formulation can be developed with this handful of evidence.

Relationship Between The BRAF V600E And Tumor Size, Lymph Node, And Distant Metastasis In Papillary Thyroid Carcinoma

Aim – This study aimed to analyze the association between B-Raf proto-oncogene, serine/threonine kinase (BRAF) V600E and tumor size, lymph node, and distant metastasis (TNM) status on patients with papillary thyroid carcinoma. Material and Methods – This research is a cross-sectional study. A total of 40 samples were papillary thyroid carcinoma tissue paraffin blocks from thyroidectomy surgery at State General Hospital (RSUP) Dr. Kariadi Semarang. Assessment of BRAF V600E mutation protein expression through immunohistochemical methods using antibody BRAF V600E was conducted. Results – The mean age of patients with papillary thyroid carcinoma with a positive BRAF V600E mutation was 49 years. The highest incidence was 71.4% in women. A significant difference between BRAF V600E and tumor size (p=0.03) was observed with as many as 53.2% more cases at size > 4 cm. A significant difference in the expression of BRAF V600E with enlargement of the lymph node (p=0.011) by 60.7% was observed compared to those without enlarged lymph nodes. On the other hand, no significant relationship between BRAF V600E expression and distant metastasis (p=0.652) was observed. The prevalence ratio in the positive BRAF V600E case at tumor size is more than 4 cm, and enlargement of lymph is 9.533 and 7.727. Conclusion – There is a significant relationship between BRAF V600E expression and tumor size and enlarged lymph nodes, while there is no significant relationship between BRAF V600E expression and distant metastases.

Risk and Prognostic Factors for BRAFV600E Mutations in Papillary Thyroid Carcinoma

Background

Over the past ten years, the incidence rate of papillary thyroid carcinoma (PTC) worldwide has been increasing rapidly year by year, with the incidence rate increasing 6% annually. PTC has become the malignant tumor with the highest growth rate in the world that fourteen PTC-related mutant genes have been identified. Whether the BRAF^V600E mutation related to more aggressive clinicopathologic features and worse outcome in PTC remains variable and controversial. We aim to investigate the risk factors that may predict the BRAF^V600E mutation potential of these lesions and new prevention strategies in PTC patients.

Methods

A total of 9,908 papillary thyroid carcinoma patients with average 74.6% BRAF^V600E mutations were analyzed (RevMan 5.3 software) in this study. The PubMed, Embase, and ISI Web of Science databases were systematically searched for works published through December 15, 2021.

Results

The following variables were associated with an increased risk of BRAF^V600E mutation in PTC patients: age ≥ 45 years (OR = 1.39, 95%CI = 1.21–1.60, p < 0.00001), male gender (OR = 1.13, 95%CI = 0.99–1.28, p = 0.06), multifocality (OR = 1.22, 95%CI = 1.07–1.40, p = 0.004), lymph node metastasis (OR = 1.33, 95%CI = 0.79–2.23, p = 0.28), extrathyroidal extension + (OR = 1.61, 95%CI = 1.06–2.44, p = 0.03), vascular invasion + (OR = 2.04, 95%CI = 1.32–3.15, p = 0.001), and tumor node metastasis stage (OR = 1.61, 95%CI = 1.38–1.88, p < 0.00001). In addition, tumor size (>1 cm) (OR = 0.51, 95%CI = 0.32–0.81, p = 0.005) and distant metastasis (OR = 0.69, 95%CI = 0.22–2.21, p = 0.54) had no association or risk with BRAF^V600E mutation in PTC patients.

Conclusion

Our systematic review identified the following significant risk factors of BRAF^V600E mutation in PTC patients: age (≥45 years), gender (male), multifocality, lymph node metastasis, vascular invasion, extrathyroidal extension, and advanced tumor node metastasis stage (stages III and IV). Tumor size (>1 cm) and distant metastasis do not appear to be correlated with BRAF^V600E mutation in PTC patients.

Development of a Molecular Assay for Detection and Quantification of the BRAF Variation in Residual Tissue From Thyroid Nodule Fine-Needle Aspiration Biopsy Specimens

Importance

Thyroid cancer, predominantly papillary thyroid carcinoma (PTC), is common, but an estimated 30% of ultrasonography-guided fine-needle aspiration (FNA) biopsies of thyroid nodules are indeterminate. BRAF variation, associated with poor clinicopathological characteristics, is a useful molecular marker for diagnostics.

Objective

To develop a sensitive molecular assay for BRAF V600E detection in remaining tissue of thyroid FNA biopsies to identify patients with cancer carrying a BRAF variation.

Design, Setting, and Participants

This diagnostic study used tumor tissue from surgical formalin-fixed, paraffin-embedded (FFPE) specimens and residual tissue from thyroid FNA biopsies for genomic DNA extraction. FFPE specimens served as the validation set, and residual tissue from FNA biopsies served as the test set. A molecular assay was developed for accurate detection of BRAF V600E variation using locked nucleic acid (LNA) probe-based droplet digital polymerase chain reaction (dPCR), and the assay was validated by BRAF V600E immunohistochemical staining (IHC). The study was conducted between February 2019 and May 2021.

Results

A total of 271 specimens, including 77 FFPE specimens (with a follow-up of 48 matched surgical specimens) and 146 residual FNA samples, were collected from 223 patients (mean [SD] age, 53.8 [15.3] years; 174 [78.0%] women; 49 [22.0%] men). The molecular assay by dPCR was first established to specifically and accurately detect and quantify wild-type BRAF and variant BRAF in DNA from human follicular thyroid carcinoma-derived FTC-133 and papillary thyroid carcinoma-derived BCPAP cells. The linearity of quantification of BRAF V600E was calculated (y = 0.7339x; R2 = 0.9996) with sensitivity at 0.02 copies/μL and reproducibility in detecting variant DNA at various dilutions(coefficient of variance in 0.3% DNA, 9.63%; coefficient of variance in 1.0% DNA, 7.41%). In validation testing, the dPCR assay and IHC staining exhibited 100% specificity in concordantly identifying BRAF V600E in PTCs (κ = 0.873; P < .001) and sensitivity of 32.0% (95% CI, 19.1% to 44.9%) in dPCR and 26.0% (95% CI, 13.1% to 38.9%) in IHC staining, with an improvement by 23.08% in dPCR compared with the IHC staining. The dPCR assay further detected BRAF V600E in 39 of 146 residual FNA specimens (26.7%). At short-term follow-up, 48 patients, including 14 of 39 patients with BRAF variation and 34 of 107 patients without BRAF variation on residual FNA specimens, underwent resection. The dPCR assay of BRAF status in the matched surgical specimens showed BRAF V600E variations in 12 patients and wild-type BRAF in 36 patients, with a high agreement to that in residual tissue of FNA specimens (κ = 0.789; P < .001). Among 14 patients with BRAF variations on residual FNA, 13 were diagnosed with PTC and 1 was diagnosed with anaplastic thyroid cancer at the thyroidectomy.

Conclusions and Relevance

This diagnostic study developed a sensitive molecular assay for detection and quantification of BRAF V600E variation in residual tissue from thyroid FNA biopsies to identify patients with cancer harboring BRAF V600E in a cost-effective manner, highlighting the clinical value of molecular assay of the remaining FNA tissue in the management of thyroid nodules.

The clinical usefulness of chemokine C-X-C Motif Ligand 12 as a diagnostic marker for Papillary Thyroid Carcinoma

Background

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer worldwide. It is essential to develop methods for the accurate diagnosis of PTC to avoid unnecessary surgery. The chemokine C-X-C motif ligand 12 (CXCL12) is associated with various cancers. We aimed to investigate the efficacy of CXCL12 in the diagnosis of PTC in fine-needle aspiration (FNA) specimens.

Methods

We prospectively collected samples from 58 patients who were scheduled for surgical treatment of PTC from 2013 to 2015. Tissue samples of 31 people with benign thyroid conditions were used as controls. Immunocytochemical and immunohistochemical staining for CXCL12 was performed on FNAs and corresponding tissue specimens. B-type Raf kinase (BRAF) V600E mutant protein expression and gene mutation were also analyzed to compare the clinical usefulness.

Results

: The mean age of the patients was 49.1 ± 1.4 years and 88.1% were women. Positive CXCL12 staining was observed in 6.5% of benign and in 98.3% of PTC samples; positive BRAF V600E mutant protein expression was found in 19.4% of benign and 93.1% of PTC samples. For the diagnosis of PTC for CXCL12 staining of FNA specimens, the calculated values were 93.1% sensitivity, 90.3% specificity, 94.7% positive predictive value, 87.5% negative predictive value, and 89.1% accuracy. CXCL12 had 100% sensitivity and specificity for the 12 cases of atypia of undetermined significance (AUS) diagnosed in FNA specimens.

Conclusions

CXCL12 may be a useful diagnostic tool for PTC, especially when the FNA specimen is classified as AUS.

Expression of Estrogen and Progesterone Receptors in Papillary Thyroid Carcinoma in Korea

Purpose

The aim of this study was to examine the rate of expression of estrogen receptor α (ERα) and β1 (ERβ1), progesterone receptor (PR), and rate of overexpression of epidermal growth factor receptor (EGFR) in a relatively large cohort of patients with papillary thyroid carcinoma (PTC). We also aimed to examine whether each receptor influenced clinicopathological characteristics and prognosis of PTC.

Materials and Methods

We made a microarray of paraffin-embedded PTC surgical tissues from 436 patients. We compared the results of the immunohistochemical staining for each hormone receptor with clinicopathological characteristics.

Results

The positive expression rate of hormonal receptors was 40.4% for ERα, 83.7% for ERβ1, and 71.3% for PR in patients with PTC. Overexpression of EGFR was shown in 19.3% of patients with PTC. The age was lower (44.6±12.1 years vs. 47.1±12.5 years, p=0.040) and tumor smaller (0.96±0.69 cm vs. 1.13±0.82 cm, p=0.020) in the ERα positive group, which also showed higher PR positivity (80.7% vs. 65.0%, p < 0.001) and overexpression of EGFR (27.3% vs. 13.8%, p < 0.001). However, neither the positivity of hormone receptors nor overexpression of EGFR affected the recurrence of PTC.

Conclusion

In conclusion, most (94.6%) patients with PTC were found to exhibit positive expression for ERs or PR. We also found that neither the positive expression of hormone receptors nor overexpression of EGFR were associated with the recurrence of PTC.

Comparison of Molecular Methods and BRAF Immunohistochemistry (VE1 Clone) for the Detection of BRAF V600E Mutation in Papillary Thyroid Carcinoma: A Meta-Analysis

The evaluation of surgically resected papillary thyroid carcinomas (PTC) by immunohistochemistry (IHC) for BRAF mutation has diagnostic, prognostic and therapeutic implications. The goal of this meta-analysis was to perform a systematic review of studies using the VE1 clone (specific for detection of the BRAF V600E mutation) on formalin-fixed paraffin embedded (FFPE) thyroid surgical resection specimens for primary papillary thyroid carcinoma. The authors' molecular techniques, immunohistochemistry protocols, and scoring methods for VE1 immunostaining were also evaluated. This study included 4079 PTCs representing data from 23 studies. The results extracted from each study were split into two different groups, direct sequencing group or PCR group, based on the molecular "gold standard" method used to compare VE1 IHC staining. In the direct sequencing group, the IHC sensitivity was 100% (95% CI 0.97-1.00) and specificity 84% (95% 0.72-0.91). In the PCR group the sensitivity was 98% (95% CI 0.96-0.99) and specificity 89% (95% CI 0.82-0.94). Although immunohistochemical procedures varied by author, the overall performance of the VE1 clone shows that it is highly sensitive and relatively specific for detecting the BRAF V600E mutation in surgical resection specimens. However, standardization of immunohistochemical procedural method and scoring/interpretation criteria may improve the reliability and reproducibility for the use of VE1 clone for future practice.

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.

VE1 Immunohistochemistry Improves the Limit of Genotyping for Detecting BRAFV600E Mutation in Papillary Thyroid Cancer

Detection of BRAF^V600E is useful for making diagnosis and risk stratification of papillary thyroid carcinoma (PTC). Molecular testing, however, is not always available for routine clinical use. To assess the clinical utility and reliability of VE1 immunohistochemistry (IHC) for detecting BRAF^V600E mutation in PTC, VE1 IHC was performed on the tissue microarrays of 514 patients with PTC and was compared with Sanger sequencing results. Of 514 PTC cases, 433 (84.2%) were positive for VE1 expression. Among 6 discordant cases between VE1 IHC and Sanger sequencing, 3 initial VE1-false negative cases turned out to be true false negative on repeat testing, and 3 VE1-false positive cases showed BRAF^V600E mutation using digital PCR analysis. PTCs with low variant allele fraction were positive for VE1 IHC but were not detected using sequencing. VE1 IHC showed 99.3% sensitivity, 100% specificity, 100% positive predictive value, and 96.4% negative predictive value. The BRAF^V600E mutation was significantly associated with older age, multifocality, extrathyroidal extension, lymph node metastasis, and advanced tumor stage. In conclusion, VE1 IHC is a reliable method for detecting BRAF^V600E mutation in PTC specimens.

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.

A Systematic Review and Meta-Analysis of the Diagnostic Performance of BRAF V600E Immunohistochemistry in Thyroid Histopathology

Immunohistochemistry (IHC) in evaluating thyroid surgical specimens may facilitate diagnostic and prognostic evaluation, with potential therapeutic implications. We performed a systematic review and meta-analysis examining the analytic validity of IHC in detecting BRAFV600E mutations in thyroid cancer (primary or metastatic). We screened citations from three electronic databases (until December 20, 2018), supplemented by a hand search of authors' files and cross-references of reviews. Citations and full-text papers were independently reviewed in duplicate, and consensus was achieved on inclusion of papers. Two reviewers independently critically appraised and abstracted data from included papers. Random-effect meta-analyses were conducted for sensitivity and specificity estimates. We reviewed 1499 unique citations and 93 full-text articles. We included 1 systematic review and 30 original articles. The published review (from 2015) needed to be updated as there were multiple subsequent original studies. The pooled sensitivity of IHC in detecting a BRAFV600E mutation was 96.8% (95% confidence interval [CI] at 94.1%, 98.3%) (29 studies, including 2659 BRAFV600E mutant tumors). The IHC pooled specificity was 86.3% (95% CI 80.7%, 90.4%) (28 studies, including 1107 BRAFV600E wild-type specimens). These meta-analyses were subject to statistically significant heterogeneity, partly explained by antibody type (sensitivity and specificity) and tissue/tumor type (specificity). In conclusion, BRAF IHC is highly sensitive and reasonably specific in detecting the BRAFV600E mutation; however, there is some variability in analytic performance.

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.

BRAF Testing in Multifocal Papillary Thyroid Carcinoma

BACKGROUND

BRAF V600E mutation is associated with poor prognosis in patients with papillary thyroid carcinoma (PTC). PTC is often multifocal, and there are no guidelines on how many tumors to test for BRAF mutation in multifocal PTC.

METHODS

Fifty-seven separate formalin-fixed and paraffin-embedded PTCs from twenty-seven patients were manually macrodissected and tested for BRAF mutation using a commercial allele-specific real-time polymerase chain reaction-based assay (Entrogen, Woodland Hills, CA). Data related to histologic characteristics, patient demographics, and clinical outcomes were collected.

RESULTS

All mutations detected were BRAF V600E. Seventeen patients (63%) had concordant mutation status in the largest and second-largest tumors (i.e., both were positive or both were negative). The remaining ten patients (37%) had discordant mutation status. Six of the patients with discordant tumors (22% overall) had a BRAF-negative largest tumor and a BRAF-positive second-largest tumor. No histologic feature was found to help predict which cases would be discordant.

CONCLUSIONS

Patients with multifocal PTC whose largest tumor is BRAF-negative can have smaller tumors that are BRAF-positive. Therefore, molecular testing of more than just the dominant tumor should be considered. Future studies are warranted to establish whether finding a BRAF mutation in a smaller tumor has clinical significance.

BRAF Immunohistochemistry Using Clone VE1 is Strongly Concordant with BRAF(V600E) Mutation Test in Papillary Thyroid Carcinoma

The aim of this study was to investigate the concordance between BRAF(V600E) mutation test and immunohistochemistry (IHC) and determine the diagnostic accuracy of IHC for papillary thyroid carcinoma (PTC) through a systematic review, meta-analysis, and diagnostic test accuracy review. The current systematic review and meta-analysis included 1141 PTCs in 11 eligible studies. We investigated the concordance rate and performed subgroup analysis using tissue and cytologic samples. Diagnostic test accuracy review was conducted and calculated using the value of area under curve (AUC) on the summary receiver operating characteristic (SROC) curve. The positive rate of BRAF IHC was 79.1% (903 of 1141 cases), and the BRAF(V600E) mutation was found in 76.6% (874 of 1141 cases). The concordance rates were 0.921 (95% confidence interval (CI) 0.877-0.950) and 0.894 (95% CI 0.801-0.946) in IHC positive and negative subgroups, respectively. In the diagnostic test accuracy review, the pooled sensitivity and specificity were 0.97 (95% CI 0.95-0.98) and 0.78 (95% CI 0.72-0.83). The value of AUC on SROC curve was 0.983, and diagnostic odds ratio was 164.28 (95% CI 57.69-467.80). Our results showed that BRAF IHC was strongly concordant with BRAF mutation test and had high diagnostic accuracy in BRAF mutation analysis of PTC.

VE1 immunohistochemical detection of the BRAF V600E mutation in thyroid carcinoma: a review of its usefulness and limitations

The BRAF V600E mutation is a valuable prognostic factor in thyroid carcinoma despite lingering debate. Successful immunohistochemical (IHC) detection of the BRAF V600E mutation using a VE1 antibody was introduced recently. The objective of this study was to verify the usefulness of IHC detection of the BRAF V600E mutation in thyroid carcinoma using the VE1 antibody. IHC detection of BRAF V600E was performed on various thyroid carcinoma subtypes. IHC results were compared with those obtained from real-time polymerase chain reaction (PCR) detection. Discordant cases were re-examined using a direct sequencing method following nested PCR amplification. The BRAF V600E mutation was detected in 68 % (71/104) of papillary carcinoma cases and 78 % (7/9) of anaplastic carcinoma cases. The mutation was not detected in patients with follicular carcinoma (0/18) or in medullary carcinoma (0/21). The overall sensitivity and specificity of IHC using the VE1 antibody were 100 and 94 %, respectively, suggesting that molecular-based results were indeterminable in four VE1-positive cases. IHC using the VE1 antibody is a highly sensitive and specific method for BRAF V600E mutation detection and may represent a future replacement for DNA-based molecular tests.