<Emphasis Type="Italic">BRAF</Emphasis><Superscript>V600E</Superscript> Mutation in Papillary Thyroid Carcinoma: Significant Association with Node Metastases and Extra Thyroidal Invasion

B-Raf (BRAF) is the strongest activator in the downstream of MAP kinase signaling. The somatic point mutation of BRAF gene (V600E) is the most common and specific event in papillary thyroid carcinoma (PTC). However, its prevalence is variable among different studies and its association with clinico-pathological features is controversial. This study tests the prevalence of BRAF ^V600E mutation in thyroid cancer patients in Indian subcontinental population. We analyzed 140 thyroid tumor specimens for BRAF gene mutation at codon 600 using mutant-allele-specific amplification, single-strand conformation polymorphism, Mutector assay, and DNA sequencing of the PCR-amplified exon 15. BRAF mutation at codon 600 was detected in 46 of 86 PTC patients (53.4%) from Indian subcontinental cohort. Frequency of mutation varied across the subtypes of PTCs. BRAF ^V600E mutation was more common in the conventional PTC (38 out of 62; 61%) than in the follicular variant of PTC (2 out of 17; 11.7%). None of the 8 follicular thyroid adenomas, 14 follicular thyroid carcinomas, 16 medullary thyroid carcinomas, and 16 benign hyperplasia patients showed any exon 15 mutation. We found significant correlation between BRAF mutation status and extra-thyroidal invasion, lymph node metastasis, and tumor stage. However no correlation was observed with gender, age, and tumor size of the patients. Thus our findings suggest that BRAF ^V600E is a prevalent genetic alteration in adult sporadic PTCs in Indian cohort and it may be responsible for the progression of classic variant of PTC to metastatic and poorly differentiated subtype and likely to have significant impact on its diagnostic and prognostic management.     

<Emphasis Type="Italic">BRAF</Emphasis> mutations typical of papillary thyroid carcinoma are more frequently detected in undifferentiated than in insular and insular-like poorly differentiated carcinomas

Somatic mutations of the BRAF gene (BRAF^V599E and BRAF^K600E) were found to be closely associated with different histotypes of papillary thyroid carcinoma (PTC). The V599E mutation is highly prevalent in PTC with a papillary or mixed papillary follicular growth pattern, and the K600E mutation is apparently restricted to the follicular variant of PTC. It is usually accepted that thyroid malignancies may follow a progression path from well-differentiated to poorly differentiated (PDC) and undifferentiated (UC) carcinomas. One would expect that at least some of the less differentiated carcinomas would harbour the genetic alterations of pre-existing well-differentiated tumours. In order to find the prevalence of BRAF mutations in PDC and UC, we screened a series of 19 PDCs and 17 UCs, as well as 3 UC-derived cell lines, for both mutation types. The group of PDCs was restricted to the so-called insular and insular-like PDCs, thus excluding PTCs with solid, insular or trabecular foci of growth and PDCs displaying typical PTC nuclei. No BRAF mutations were detected in any of the 19 cases of PDC, whereas 6 of the UCs (35%) and one UC-derived cell line presented the BRAF^V599E mutation. The BRAF^K600E mutation was not detected in any case. We conclude that UC may progress from BRAF^V599E-mutated PTC. The absence of BRAF mutations in our series of PDC supports the assumption that pure insular and insular-like PDCs are more closely related to follicular carcinoma than to PTC.Paula Soares and Vítor Trovisco contributed equally to this work.     

Papillary thyroid carcinomas with and without BRAF V600E mutations are morphologically distinct

Finkelstein A, Levy G H, Hui P, Prasad A, Virk R, Chhieng D C, Carling T, Roman S A, Sosa J A, Udelsman R, Theoharis C G & Prasad M L
(2012) Histopathology  60, 1052–1059 Papillary thyroid carcinomas with and without BRAF V600E mutations are morphologically distinct Aims: The BRAF V600E mutation resulting in the production of an abnormal BRAF protein has emerged as the most frequent genetic alteration in papillary thyroid carcinomas (PTCs). This study was aimed at identifying distinctive features in tumours with and without the mutation. Methods and results: Thirty‐four mutation‐positive and 22 mutation‐negative tumours were identified by single‐strand conformation polymorphism of the amplified BRAF V600E region in the tumour DNA. Mutation‐positive tumours were more common in patients older than 45 years (24/33, P = 0.05), in classic (23/30, P = 0.01), tall cell (4/5) and oncocytic/Warthin‐like (2/2) variants of PTC, and in subcapsular sclerosing microcarcinomas (4/4). In contrast, all 12 follicular variants (P < 0.0001) and two diffuse sclerosing variants were negative for the mutation. Mutation‐positive tumours displayed infiltrative growth (32/34, P = 0.02), stromal fibrosis (33/34, P < 0.001), psammoma bodies (17/34, P = 0.05), plump eosinophilic tumour cells (22/34, P = 0.01), and classic fully developed nuclear features of PTC (33/34, P = 0.0001). Encapsulation was significantly associated with mutation‐negative tumours (15/22, P = 0.02). Conclusions: BRAF V600E mutation‐positive and negative PTCs are morphologically different. Recognition of their morphology may help in the selection of appropriate tumours for genetic testing.     

Morphology predicts BRAF V600E mutation in papillary thyroid carcinoma: an interobserver reproducibility study

Papillary thyroid carcinomas (PTC) with BRAF ^V600E mutation are morphologically distinctive. They are typically classic or tall cell variants, show infiltrative borders, and are associated with desmoplasia/fibrosis, psammoma bodies, and well-developed nuclear features of papillary carcinoma. We hypothesize that morphologic features of PTC can help in the prediction of BRAF ^V600E mutation, and we evaluate the accuracy and the interobserver reproducibility of such prediction. Hematoxylin and eosin-stained sections from 50 PTCs comprising of 26 mutation-positive and 24 mutation-negative tumors were examined. BRAF ^V600E mutation was predicted correctly in 42/50 tumors (accuracy, 84 %) with 96 % sensitivity, 71 % specificity, and 78 % positive and 94 % negative predictive values (NPV). Subtle nuclear features of PTC (n?=?10) had the highest (100 %) negative predictive value followed by well-circumscribed non-infiltrative tumor borders (17/22 mutation-negative tumors, 95 % NPV). The positive predictive value of infiltrative tumor borders (21/28 [75 %] mutation-positive), desmoplasia/fibrosis (23/31 [74 %] mutation-positive), and psammoma bodies (13/20 [65 %] mutation-positive) increased to 100 % when all three features were present (n?=?8/8 mutation-positive). To assess interobserver reproducibility, two pathologists blinded to the mutational status evaluated 30 PTCs (15 mutation-positive and 15 mutation-negative) after self-training on 10 PTCs with known BRAF ^V600E mutational status (five mutation-positive and five mutation-negative). The prediction of the mutation was achieved with substantial agreement (κ value, 0.79) and accuracy (25/30, 83 %). This study demonstrates that BRAF ^V600E mutation in papillary thyroid carcinoma can be predicted on morphology with accuracy and with substantial interobserver agreement.     

Type and prevalence of BRAF mutations are closely associated with papillary thyroid carcinoma histotype and patients’ age but not with tumour aggressiveness

A high prevalence of the BRAF^V600E somatic mutation was recently reported in several series of papillary thyroid carcinomas (PTC). This mutation appears to be particularly prevalent in PTC with a predominantly papillary architecture. Another BRAF mutation (K601E) was detected in a follicular adenoma and in some cases of the follicular variant of PTC. The few studies on record provided controversial data on the relationship between the occurrence of BRAF mutations and clinicopathologic parameters such as gender, age and tumour staging. In an attempt to clarify such controversies we decided to enlarge our previous series to 315 tumours or tumour-like lesions diagnosed in 280 patients, including a thorough analysis of several clinicopathologic features. The BRAF^V600E mutation was exclusively detected in PTC with a papillary or mixed follicular/papillary architecture both of the conventional type (46%) and of other histotypes, such as microcarcinoma (43%), Warthin-like PTC (75%) and oncocytic variant of PTC (55%). The BRAF^K601E mutation was detected in four of the 54 cases of the follicular variant of PTC (7%). The mean age of patients with conventional PTC harbouring BRAF^V600E (46.7 years) was significantly higher (P<0.0001) than that of patients with conventional PTC without BRAF^V600E (29.5 years). The BRAF (BRAF^V600E) mutated PTC did not exhibit signs of higher aggressiveness (size, vascular invasion, extra-thyroid extension and nodal metastasis) and were in fact less often multicentric than PTC without the mutation.V. Trovisco and P. Soares contributed equally to this workFundação para a Ciência e Tecnologia POCTI/FEDER (POCTI/NSE/48171/2002)     

Frequent <Emphasis Type="Italic">BRAF</Emphasis><Superscript><Emphasis Type="Italic">V600E</Emphasis></Superscript> and Absence of <Emphasis Type="Italic">TERT</Emphasis> Promoter Mutations Characterize Sporadic Pediatric Papillary Thyroid Carcinomas in Japan

Pediatric papillary thyroid carcinoma (PTC) has unique features but requires further genetic investigation. Moreover, there has been increasing concern about the risk for pediatric PTC in Japan after the Fukushima accident. This study aims to evaluate the frequencies of BRAF and TERT promoter mutations and to examine their significance in non-radiation-associated pediatric PTCs in Japan. We enrolled 81 pediatric PTC patients aged ≤20 years. The control group included 91 adult PTCs from patients >20 years old. BRAF and TERT mutations were analyzed by allele-specific-PCR and/or Sanger sequencing. Compared with adult PTCs, pediatric PTCs exhibited larger tumor size, more frequent lymph node metastasis, and less classical histology. The prevalence of BRAF ^V600E in pediatric PTCs was 54% and significantly lower than that in adults of 85%. In the pediatric PTCs, BRAF ^V600E was positively associated with older age, classical histology, and the lymph node metastasis but independent from other clinicopathological factors. TERT mutations were identified in 13% of adults and in none of the pediatric PTCs. In conclusion, pediatric PTCs are characterized by more advanced clinicopathological features, lower BRAF ^V600E frequency, and absence of TERT mutation. The BRAF ^V600E frequency in this study is similar to the reported BRAF ^V600E frequency in the ultrasonographically screened pediatric PTCs in Fukushima.     

Detection of Plasma BRAFV600E Mutation Is Associated with Lung Metastasis in Papillary Thyroid Carcinomas

Purpose

The BRAF^V600E mutation represents a novel indicator of the progression and aggressiveness of papillary thyroid carcinoma (PTC). The purpose of this study was to determine the clinical significance of free circulating mutant BRAF^V600E in predicting the advanced disease of PTC.

Materials and Methods

Seventy seven matched tumor and plasma samples obtained from patients with both benign and PTC were analyzed for BRAF^V600E mutation using a peptide nucleic acid (PNA) clamp real-time polymerase chain reaction (PCR).

Results

The BRAF^V600E mutation was absent in tumor DNA samples obtained from patients with benign follicular adenomas or adenomatous goiter. In contrast, 49 of 72 (68.1%) PTC tumors were positive for the BRAF^V600E mutation. Among them, 3 (6.1%) patients with PTC were positive for BRAF^V600E mutation in plasma and tumor. However, all 3 patients (100%) had lateral lymph node and lung metastasis.

Conclusion

These findings suggest that the BRAF^V600E mutation can be detected using a PNA clamp real-time PCR in the blood of PTC patients with lung metastasis. Future studies are warranted to determine clinical significance of serum BRAF^V600E mutation in large prospective studies.     

Up-regulation of urinary-type plasminogen activator correlates with high-risk papillary thyroid carcinoma with BRAFV600E mutation and its possible molecular mechanism

The aim of the present study is to investigate the relationship between urinary-type plasminogen activator (uPA) expression and clinicopathological features in papillary thyroid carcinoma (PTC) and to determine the signal transduction of PTC cells in vitro.PTC tissues from 42 patients were analyzed for the expression of uPA and the BRAF^V600E mutation. BCPAP, a PTC cell line harboring the BRAF^V600E mutation, was used to study MAPK signaling. PCR and direct sequencing were applied to analyze BRAF^V600E mutation status. uPA mRNA expression was measured using a quantitative RT-PCR method, and uPA protein was localized using an immunohistochemical method. The ERK protein status was detected by Western blot analysis.uPA gene expression was significantly increased in PTC tissues as compared to the corresponding non-tumor tissues. Furthermore, the up-regulation of uPA mRNAs was correlated with high-risk clinicopathological features, including extrathyroid invasion, loss of cellular polarity/cohesiveness, and the BRAF^V600E mutation. Marked dephosphorylation of ERK1/2 and down-regulation of uPA expression were detected when BCPAP was treated with a MEK inhibitor, U0126.MEK inhibitors might be a potential treatment strategy for aggressive PTC with BRAF^V600E through inhibition of uPA expression.     

DHPLC is a highly sensitive and rapid screening method to detect BRAF mutation in papillary thyroid carcinoma

The BRAF^V600E mutation has been reported to occur in 30% to 80% of papillary thyroid carcinomas (PTCs). Although direct sequencing is the method most commonly used to identify mutations, this technique is not sensitive enough to accurately detect low level mutation. To determine the optimal diagnostic method for detecting the BRAF^V600E mutation in PTC, we compared the diagnostic efficacy of four representative detection methods in formalin-fixed paraffin-embedded thyroid tissues obtained from 40 patients diagnosed with PTC. To detect the BRAF^V600E mutation, we amplified exon 15 of the BRAF gene and performed mutational analysis with direct sequencing, denaturing high-performance liquid chromatography (DHPLC), pyrosequencing and colorimetric assay. The BRAF mutation was detected in 33 cases (82.5%) by DHPLC, 23 cases (57.5%) by direct sequencing, 22 cases (55.0%) by pyrosequencing, and 37 cases (92.5%) by colorimetric assay. The sensitivity, negative predictive value and accuracy of DHPLC were 100%. The specificity and positive predictive values for DHPLC, direct sequencing and pyrosequencing were 100%, and for colorimetric assay they were 14.3% and 83.8%, respectively. The kappa value for DHPLC was a perfect 1.0, which was superior to the other methods. In conclusion, DHPLC is a sensitive, specific and accurate method for detecting the BRAF^V600E mutation, especially low level mutation, in PTC.     

<Emphasis Type="Italic">BRAF</Emphasis><Superscript><Emphasis Type="Italic">V600E</Emphasis></Superscript> Mutation Analysis from May-Grünwald Giemsa-Stained Cytological Samples as an Adjunct in Identification of High-Risk Papillary Thyroid Carcinoma

The BRAF ^V600E mutation is specific for thyroid papillary cancer (PTC) and correlates with PTCs invasiveness. This study investigated whether detection of BRAF ^V600E mutation can be performed on routinely stained FNABs. We also examined if establishment of the BRAF ^V600E mutation could help in identification of patients at higher risk for metastatic disease. DNA was isolated from 134 FNABs samples (20 follicular neoplasm, ten suspicious for malignancy, and 104 malignant) using Pinpoint Slide DNA Isolation System. BRAF ^V600E mutation was detected by PCR followed by sequencing. DNA was successfully extracted from all examined FNABs samples. In follicular neoplasm, suspicious for malignancy and malignant FNABs, BRAF ^V600E mutation was found in 0/20 (0%), 2/10 (20%), and 47/104 (45.2%) of cases, respectively. Extra-thyroidal extension was detected in 35/47 (74.4%) BRAF ^V600E positive and in 24/57 (42.1%) wild-type BRAF cases (p = 0.001). Metastases were detected in 37/47 (78.7%) BRAF ^V600E positive and in 28/57 (49.1%) wild-type BRAF cases (p = 0.002). Our results showed that stained FNAB specimens can be used for DNA extraction and assessment of BRAF ^V600E mutation. Detection of BRAF ^V600E mutation had limited value in diagnoses of malignancy in follicular neoplasms but can ascertain malignancy in subset of suspicious for malignancy FNABs. In malignant FNABs, BRAF ^V600E mutation was significantly associated with presence of extra-thyroidal extension and metastases after surgery.     

Investigation of BRAF mutation in a series of papillary thyroid carcinoma and matched-lymph node metastasis with ARMS PCR

Objectives

To figure out that if there is a consistency relationship of the BRAF^V600E mutation in matched-lymph node metastasis and original papillary thyroid carcinoma (PTC) specimen for the same patient.

Association of BRAFV600E mutation with clinicopathological features of papillary thyroid carcinoma: a study on a Chinese population

Background: The new finding of the heterogeneous distribution of BRAF^V600E mutation in primary papillary thyroid carcinoma suggested the percentage of BRAF^V600E alleles should be taken into consideration when evaluating its association with clinicopathological features of papillary thyroid carcinoma. The aim of this study was to detect both the presence and the percentage of BRAF^V600E alleles in fine-needle aspiration biopsy samples and to assess its association with clinicopathological characteristics of papillary thyroid carcinoma in a Chinese population. Materials and methods: Fine needle aspiration samples were collected in a total of 182 patients (132 conventional papillary thyroid carcinomas and 50 goiters). The associations of the presence and percentage of BRAF^V600E alleles genotyped by pyrosequencing with clinicopathological characteristics were evaluated in papillary thyroid carcinomas. Results: 80 (60.61%) of papillary thyroid carcinomas exhibited BRAF^V600E mutation in a range of 7.7% to 46.3% of the total BRAF alleles. The presence of BRAF^V600E mutation was significantly associated with extrathyroidal invasion. There was no significant difference between the presence of BRAF^V600E mutation and other clinicopathological features. It was not found that the significant relationship between percentage of BRAF^V600E alleles and clinicopathological characteristics. Conclusion: We concluded that the presence of BRAF^V600E could be preoperatively predictive of extrathyroidal invasion in a Chinese population.     

BRAFV600E hot spot mutation in thyroid carcinomas: first Moroccan experience from a single-institution retrospective study

BackgroundThe incidence of thyroid cancer is increasing worldwide at an alarming rate. BRAF^V600E mutation is described to be associated with a worse prognostic of thyroid carcinomas, as well as extrathyroidal invasion and increased mortality.ObjectiveTo our knowledge, there are no reported studies neither from Morocco nor from other Maghreb countries regarding the prevalence of BRAF^V600E mutation in thyroid carcinomas. Here we aim to evaluate the frequency of BRAF^V600E oncogene in Moroccan thyroid carcinomas.MethodsIn this Single-Institution retrospective study realized in the Anatomic Pathology and Histology Service in the Military Hospital of Instruction Mohammed V ‘HMIMV’ in Rabat, we report, using direct genomic sequencing, the assessment of BRAF^V600E in 37 thyroid tumors.ResultsWe detected BRAF^V600E mutation exclusively in Papillary Thyroid Carcinomas ‘PTC’ with a prevalence of 28% (8 PTC out 29 PTC). Like international trends, Papillary Thyroid Carcinomas ‘PTC’ is more frequent than Follicular Thyroid Carcinomas ‘FTC’ and Anaplastic Thyroid Carcinomas ‘ATC’ (29 PTC, 7 FTC and 1 ATC).ConclusionOur finding gives to the international community the first estimated incidence of this oncogene in Morocco showing that this prevalence falls within the range of international trends (30% to 90%) reported in distinct worldwide geographic regions.     

Thyroid stimulating hormone levels and BRAFV600E mutation contribute to pathophysiology of papillary thyroid carcinoma: Relation to outcomes?

AimsThe aim of this study was to evaluate the relation between the level of thyroid stimulating hormone (TSH) and progression of papillary thyroid carcinoma (PTC) with or without BRAF^V600E mutation.MethodsThe medical records and laboratory data of 547 patients with PTC and 94 patients with follicular adenoma (FA) were collected. The relationship between hormones levels and such end-points as extrathyroid extension (ETE), lymphovascular invasion (LVI) and lymph node metastasis (LNM) was assessed. In addition, age, gender, BRAF^V600E mutation status, histological type and Hashimoto’s thyroiditis (HT) were considered.Key findingsMost of the patients with PTC had hormones levels within the normal range, however, serum TSH concentration was significantly higher in PTC comparing with FA (P = 0.022). High levels of TSH in PTC were more frequent among women rather than men (P = 0.03) due to the gender differences in coexisting HT rate (P = 0.003). In contrast, LNM rate was higher in men (P = 0.0014). Coexisting HT significantly decreased the risk of ETE (OR = 0.67; 95%CI 0.44–1.00; P = 0.05) and LNM (OR = 0.59; 95%CI 0.37?0.94; P = 0.028) among males with PTC. However, there was no significant relationship between HT and PTC-related ETE and LNM in females. BRAF^V600E mutation was associated with presence of lymphocytic infiltration (P < 0.001) but not with HT (P = 0.08) and violation of thyroid function.ConclusionThe present study showed the lack of significant relationship between TSH levels and PTC aggressiveness (LNM, TNM stage, BRAF^V600E mutation). Higher TSH levels were found in patients with coexisting HT that was associated with female sex and multifocality of PTC.     

Critical Pitfalls in the use of <Emphasis Type="Italic">BRAF</Emphasis> Mutation as a Diagnostic Tool in Thyroid Nodules: a Case Report

Thyroid fine-needle aspiration (FNA) cytology is the primary tool for the diagnostic evaluation of thyroid nodules. BRAF mutation analysis is employed as an ancillary tool in indeterminate cases, as recommended by the American Thyroid Association management guidelines. Hereby, we report the case of a 73-year-old woman who presented an 8-mm-size, ill-defined, left thyroid nodule. FNA resulted “suspicious for papillary thyroid carcinoma”. BRAF mutation status was analyzed, and somatic BRAF ^V600E mutation identified. The patient underwent a total thyroidectomy. At histological examination, the nodule was composed of Langerhans cells, admixed with many eosinophils. A final diagnosis of Langerhans cell histiocytosis of the thyroid was made. Our case emphasizes the critical diagnostic pitfalls due to the use of BRAF ^V600E mutation analysis in thyroid FNA. Notably, BRAF ^V600E mutation is common in melanoma, colorectal carcinoma, lung carcinoma, ovarian carcinoma, brain tumors, hairy cell leukemia, multiple myeloma, and histiocytoses. Therefore, in cases of indeterminate FNA with unclassifiable atypical cells BRAF ^V600E mutated, the possibility of a localization of hystiocytosis or a secondary thyroid malignancy should be taken into account.     

BRAF mutation is unusual in chronic lymphocytic thyroiditis-associated papillary thyroid carcinomas and absent in non-neoplastic nuclear atypia of thyroiditis

Chronic lymphocytic thyroiditis (CLT) has an epidemiological relationship to papillary thyroid carcinoma (PTC). The follicular epithelium in CLT can be markedly atypical, with cytologic changes ranging from oncocytic morphology to clearing and overlapping. At the molecular level, the association between CLT and PTC is more controversial. In order to further characterize the molecular changes in CLT, this study examined the BRAF gene in 27 patient samples with CLT and without carcinoma and 28 samples with CLT and carcinoma (12 conventional papillary carcinomas, 13 follicular variants, and 3 tall cell variants). Microdissection, PCR, and sequencing of exon 15 of the BRAF gene were performed. BRAF mutations were uncommon in the cases studied with only two microscopic and two clinically sized PTCs had BRAF mutations (14%). There was no evidence of BRAF mutation in any of the areas with atypical follicular epithelium in CLT. These data suggest that BRAF is a less frequent mechanism of tumorigenesis in a background of CLT and that BRAF mutation is not present in the atypical follicular epithelium of CLT.     

Effect of BRAF V600E mutation detection of fine-needle aspiration biopsy on diagnosis and treatment guidance of papillary thyroid carcinoma

ObjectiveThe aim of this study was to evaluate the diagnostic value of detection of BRAF V600E mutation in the fine-needle aspiration cytology (FNAC) specimens of thyroid nodules and the relationship between BRAF V600E mutation and the clinicopathological characteristics of papillary thyroid carcinoma (PTC).MethodsA total of 252 patients who underwent initial thyroid surgery were retrospectively analysed. All the patients underwent a preoperative FNAC at our institution, and the thyroid puncture cell fluid was used for both the cytological diagnosis and BRAF V600E mutational analysis using quantitative polymerase chain reaction. The Cochran-Mantel-Haenszel test was used to evaluate the diagnostic value of BRAF V600E mutation in FNAC fluid in diagnosing PTC. The association between BRAF V600E mutation and the clinicopathological parameters of PTC was analysed using the χ² test.ResultsThrough FNAC, 21 (8%), 60 (24%), and 171 (68%) cases were cytologically diagnosed as benign, indeterminate, and malignant, respectively. Postoperatively, 242 cases were histopathologically diagnosed as PTCs and 10 as goitre nodules. In the FNAC samples, 12 (57 %) of the 21 benign, 48 (80 %) of the 60 indeterminate, and 152 (88.9 %) of the 171 malignant cases showed BRAF V600E mutation. The histopathological diagnosis was used as the gold standard. The sensitivity and specificity of BRAF V600E mutational analysis in the FNAC samples for the diagnosis of PTC were 91.7 % and 100 % in benign, 82.8 % and 100 % in the indeterminate, and 89.4 % and 100 % in the malignant cases, respectively.ConclusionBRAF V600E mutational analysis in FNAC samples of thyroid nodules can be used an effective supplementary diagnostic method at our institution. However, BRAF V600E mutation was not associated with aggressive characteristics in PTC.     

Dysembryoplastic Neuroepithelial Tumors Share with Pleomorphic Xanthoastrocytomas and Gangliogliomas BRAFV600E Mutation and Expression

Pediatric cortical glioneuronal benign tumors mainly include gangliogliomas (GG) [differential diagnoses pilocytic astrocytomas (PA) and pleomorphic xanthoastrocytomas (PXA)] and dysembryoplastic neuroepithelial tumor (DNT). DNT include the specific form and the controversial non‐specific form that lack the specific glioneuronal element. Our aims were to search for BRAF^V600E mutation and CD34 expression in DNT, PXA, GG and PA to correlate BRAF^V600E mutation with BRAF^V600E expression and to evaluate their diagnostic and prognostic values. Ninety‐six children were included. BRAF^V600E mutation was studied by sequencing and immunohistochemistry; CD34 expression was analyzed by immunohistochemistry. BRAF^V600E mutation was detected in PXA (60%), GG (38.7%), DNT (30%, including 3/11 specific and 3/9 non‐specific forms) and PA (12.5%). BRAF^V600E expression was recorded in PXA (60%), GG (45.2%) and DNT (30%). CD34 expression was recorded in PXA (60%), GG (58.1%), DNT (25%) and PA (12.5%). Neither CD34 expression nor BRAF^V600E status was predictive of prognosis, except for PA tumors where CD34 expression was associated with a shorter overall survival. In conclusion, DNT shared with PXA and GG, BRAF^V600E mutation and/or CD34 expression, which represent molecular markers for these tumors, and we recommend searching for CD34 expression and BRAF^V600E mutation in all DNT, especially the non‐specific forms.