The role of BRAFV600E mutation and ultrasonography for the surgical management of a thyroid nodule suspicious for papillary thyroid carcinoma on cytology

Imaging Analytics using Artificial Intelligence in Oncology: A Comprehensive Review

The present era has seen a surge in artificial intelligence-related research in oncology, mainly using deep learning, because of powerful computer hardware, improved algorithms and the availability of large amounts of data from open-source domains and the use of transfer learning. Here we discuss the multifaceted role of deep learning in cancer care, ranging from risk stratification, the screening and diagnosis of cancer, to the prediction of genomic mutations, treatment response and survival outcome prediction, through the use of convolutional neural networks. Another role of artificial intelligence is in the generation of automated radiology reports, which is a boon in high-volume centres to minimise report turnaround time. Although a validated and deployable deep-learning model for clinical use is still in its infancy, there is ongoing research to overcome the barriers for its universal implementation and we also delve into this aspect. We also briefly describe the role of radiomics in oncoimaging. Artificial intelligence can provide answers pertaining to cancer management at baseline imaging, saving cost and time. Imaging biobanks, which are repositories of anonymised images, are also briefly described. We also discuss the commercialisation and ethical issues pertaining to artificial intelligence. The latest generation generalist artificial intelligence model is also briefly described at the end of the article. We believe this article will not only enrich knowledge, but also promote research acumen in the minds of readers to take oncoimaging to another level using artificial intelligence and also work towards clinical translation of such research.

Artificial intelligence to predict the BRAFV600E mutation in patients with thyroid cancer

Purpose

To investigate whether a computer-aided diagnosis (CAD) program developed using the deep learning convolutional neural network (CNN) on neck US images can predict the BRAF^V600E mutation in thyroid cancer.

Methods

469 thyroid cancers in 469 patients were included in this retrospective study. A CAD program recently developed using the deep CNN provided risks of malignancy (0–100%) as well as binary results (cancer or not). Using the CAD program, we calculated the risk of malignancy based on a US image of each thyroid nodule (CAD value). Univariate and multivariate logistic regression analyses were performed including patient demographics, the American College of Radiology (ACR) Thyroid Imaging, Reporting and Data System (TIRADS) categories and risks of malignancy calculated through CAD to identify independent predictive factors for the BRAF^V600E mutation in thyroid cancer. The predictive power of the CAD value and final multivariable model for the BRAF^V600E mutation in thyroid cancer were measured using the area under the receiver operating characteristic (ROC) curves.

Results

In this study, 380 (81%) patients were positive and 89 (19%) patients were negative for the BRAF^V600E mutation. On multivariate analysis, older age (OR = 1.025, p = 0.018), smaller size (OR = 0.963, p = 0.006), and higher CAD value (OR = 1.016, p = 0.004) were significantly associated with the BRAF^V600E mutation. The CAD value yielded an AUC of 0.646 (95% CI: 0.576, 0.716) for predicting the BRAF^V600E mutation, while the multivariable model yielded an AUC of 0.706 (95% CI: 0.576, 0.716). The multivariable model showed significantly better performance than the CAD value alone (p = 0.004).

Conclusion

Deep learning-based CAD for thyroid US can help us predict the BRAF^V600E mutation in thyroid cancer. More multi-center studies with more cases are needed to further validate our study results.

Ten tips for a text-mining-ready article: How to improve automated discoverability and interpretability

Data-driven research in biomedical science requires structured, computable data. Increasingly, these data are created with support from automated text mining. Text-mining tools have rapidly matured: although not perfect, they now frequently provide outstanding results. We describe 10 straightforward writing tips—and a web tool, PubReCheck—guiding authors to help address the most common cases that remain difficult for text-mining tools. We anticipate these guides will help authors’ work be found more readily and used more widely, ultimately increasing the impact of their work and the overall benefit to both authors and readers. PubReCheck is available at http://www.ncbi.nlm.nih.gov/research/pubrecheck.

Your published research is already being processed with automated tools, and text mining will become more common; this Community Page article describes how you can help these tools process your work more accurately, including a web tool, PubReCheck.

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

OBJECTIVE

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

METHODS AND MATERIALS

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

RESULTS

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

CONCLUSION

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

Testing for BRAF (V600E) Mutation in Thyroid Nodules with Fine-Needle Aspiration (FNA) Read as Suspicious for Malignancy (Bethesda V, Thy4, TIR4): a Systematic Review and Meta-analysis

In patients with thyroid fine-needle aspiration (FNA) report of suspicious for malignancy (SFM), both lobectomy and thyroidectomy might be considered. BRAF mutation analysis could guide towards accurate surgical therapy. The primary outcome was the reliability of BRAF (V600E) in detecting malignancy in nodules with FNA reading of SFM. The secondary outcome was to analyze its positive predictive value (PPV) and negative predictive value (NPV) considering the surgical histology as gold standard. A literature search of online databases was performed in June 2019. BRAF prevalence among thyroid nodules with FNA read as SFM according to the most popular classification systems (i.e., Bethesda V, Thy4, TIR4 category) was searched. The random-effects model was used. Three hundred sixty original articles were identified and 34 were finally included in the study. There were 1428 thyroid nodules with FNA read as SFM and 1287 (90.1%) lesions underwent surgery with a cancer rate 89.6%. The pooled prevalence of BRAF (V600E) mutation among all nodules with SFM cytology was 47% (95% CI = 40 to 54, I2 = 85.5%). Pooled PPV and NPV of BRAF testing were 99% (95% CI, 97-99) and 24% (95% CI, 16-32), respectively. BRAF (V600E) mutation was found in about one in two nodules with thyroid FNA read as SFM, its PPV to detect cancers was excellent, and its NPV was very poor. The routine BRAF testing in FNA read as SFM cannot be recommended. BRAF (V600E) test may be useful to extend surgical approach in selected cases with further suspicious clinical/ultrasound features.

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 multivariable model of BRAFV600E and ultrasonographic features for predicting the risk of central lymph node metastasis in cN0 papillary thyroid microcarcinoma

Background: Prophylactic central lymph node dissection (CLND) in papillary thyroid microcarcinoma (PTMC) patients without clinical evidence of central lymph node metastasis (CLNM) remains controversial. The purpose of our study is to identify preoperative predictive factors for finding CLNM in Chinese PTMC patients, which may allow tailored CLND. Methods: We retrospectively reviewed 182 consecutive Chinese PMTC patients with negative central lymph nodes who underwent total thyroidectomy plus central neck dissection from October 2015 to December 2017. Chi-squared and multivariate analysis were performed to evaluate the association of CLNM with ultrasonographic and clinicopathologic characteristics. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the utility of markers in predicting CLNM. Results: The CLNM was found in 39.0% (71 of 182) of cN0 PTMC patients. In multivariate analysis, tumor size>7 mm (OR: 3.636, 95% CI: 1.671-7.914), marked hypoechogenicity (OR: 2.686, 95% CI: 1.080-6.678), multifocality (OR: 4.184, 95% CI: 1.707-10.258) and BRAF^V600E mutation (OR: 5.339, 95% CI: 2.529-11.272) were independent predictors of CLNM. In ROC analysis integrating these predictors, the sensitivity was 63.4% and specificity was 80.2%, and the area under the ROC (AUC) was 0.755. Conclusion: In conclusion, we found tumor size>7 mm, marked hypoechogenicity, multifocality, and BRAF^V600E mutation were risk factors for CLNM. In term of these preoperative risk factors for CLNM, prophylactic CLND should be cautiously performed in cN0 PTMC patients.

European Perspective on 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: Proceedings of an Interactive International Symposium

BACKGROUND

The American Thyroid Association (ATA) management guidelines for patients with thyroid nodules and differentiated thyroid cancer (DTC) are highly influential practice recommendations. The latest revision appeared in 2015 ("ATA 2015"). These guidelines were developed predominantly by North American experts. European experts frequently have different perspectives, given epidemiological, technological/methodological, practice organization, and medicolegal differences between the respective regions.

SUMMARY

Divergent viewpoints were the focus of an invited symposium organized by the European Association of Nuclear Medicine involving 17 European thyroidologists, four ATA Guidelines Taskforce members, and an audience of 200 international experts. The group discussed the preoperative assessment of thyroid nodules, surgery and the role of pathology, radioiodine (RAI) therapy (RAIT), the assessment of initial therapy and dynamic risk stratification, and the treatment of persistent disease, recurrences, and advanced thyroid cancer. The dialogue resulted in this position paper contrasting European and ATA 2015 perspectives on key issues. One difference pertains to the permissiveness of ATA 2015 regarding lobectomy for primary tumors ≤4 cm. European panelists cited preclusion of RAIT, potential need for completion thyroidectomy, frequent inability to avoid chronic thyroid hormone replacement, and limitations of supportive evidence as arguments against widely applying lobectomy. Significant divergence involved ATA 2015's guidance regarding RAIT. European panelists favored wider use of postoperative RAIT than does ATA 2015. Rationales included the modality's association with favorable patient outcomes and generally limited toxicity, and lack of high-quality evidence supporting withholding RAIT. Additionally, European panelists favored recombinant human thyrotropin (rhTSH) in more settings than does ATA 2015, citing avoidance of hypothyroid morbidity and quality-of-life impairment, without apparent sacrifice in oncologic outcomes. Based on clinical evidence plus theoretical advantages, European experts advocated dosimetric versus fixed-activity RAIT approaches for advanced DTC. European panelists noted that the ATA 2015 risk-stratification system requires information sometimes unavailable in everyday practice. ATA 2015 recommendations regarding RAI-refractory DTC should consider potential palliative benefits of RAIT in patients who also have RAI-susceptible lesions.

CONCLUSIONS

European panelists suggested modifications to approximately one-third of ATA 2015 recommendations. Varying European and ATA 2015 perspectives can stimulate analysis and discussion of the literature and performance of primary research to resolve discrepant recommendations and potentially improve patient outcomes.

Identifying risk factors of lateral lymph node recurrence in clinically node-negative papillary thyroid cancer

There is still debate regarding the role of routine central lymph node (LN) dissection in treating clinically node-negative papillary thyroid cancer (PTC). The aim of this study was to investigate the risk factors for lateral recurrence after total thyroidectomy and prophylactic bilateral central LN dissection in clinically node-negative PTC patients.We retrospectively collected the medical records of 1406 PTC patients who underwent total thyroidectomy and prophylactic bilateral central LN dissection between January 2004 and December 2008. We used Cox- proportional hazards regression analyses to inspect the predictive factors for recurrence.During a median follow-up of 107 months (range, 13-164 months), 68 (4.8%) and 37 (2.6%) patients experienced recurrence in any lesion and in lateral neck LN, respectively. Male, main tumor size >1 cm, nodal factors (pathologic N1a, positive delphian LN, and LN ratio >0.15), lymphovascular invasion, and extrathyroidal extension (ETE) were significantly associated with lateral neck LN recurrence in univariate analysis. Multivariate analysis showed that male (hazard ratio [HR], 2.217; 95% confidence interval [CI], 1.057-4.647; P = .035), main tumor size >1 cm (HR, 2.257; 95% CI, 1.138-4.476; P = .020), pathologic N1a (HR, 5.957; 95% CI, 2.573-13.789; P < .002), minor ETE (vs no ETE; HR, 3.027; 95% CI, 1.315-6.966; P = .009), and gross ETE (vs no ETE; HR, 4.058; 95% CI, 1.685-9.774; P = .002) were independent predictors for lateral neck LN recurrence.Among patients with pathologic N1a, those with LN ratio of more than 0.55 had worse lateral neck LN recurrence-free survival. Lateral neck LN recurrence in clinically node-negative PTC patients is predicted by the factors of male, main tumor size >1 cm, ETE, and pathologic N1a.

Molecular testing in the diagnosis of differentiated thyroid carcinomas

Different genetic mutations and other molecular alterations in papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC) can be detected in fine-needle aspiration (FNA) of thyroid nodules, and can be used successfully to ameliorate cancer diagnosis and management of patients with thyroid nodules. The greatest experience has been obtained with the diagnostic use of BRAF mutation that is strongly specific for malignancy when detected using well-validated techniques. The strongest diagnostic result can be obtained testing FNA samples for a panel of mutations that typically involve TERT, BRAF, PAX8/PPARγ, RAS, and RET/PTC. Finding any of these mutations in a thyroid nodule provides strong indication for malignancy and helps to refine clinical management for a significant proportion of patients with indeterminate cytology. The use of molecular markers, as TERT, BRAF, PAX8/PPARγ, RAS, and RET/PTC, may be considered for patients with indeterminate FNA cytology (FNAC) to help guide management. In patients with indeterminate TIR3 FNA, the combination of precise molecular marker expression analysis with molecular mutations evaluations could ameliorate significantly the accuracy of cancer diagnosis. However other prospective studies are needed to identify more accurate molecular markers. Finally, the knowledge of these molecular pathways has permitted the development of new targeted therapies for aggressive TC.

Application of metabolomics in prediction of lymph node metastasis in papillary thyroid carcinoma

PURPOSE

The aim of this study was to find useful metabolites to predict lymph node (LN) metastasis in patients with papillary thyroid cancer (PTC) through a metabolomics approach and investigate the potential role of metabolites as a novel prognostic marker.

MATERIALS AND METHODS

Fifty-two consecutive patients (median age: 41.5 years, range 15-74 years) were enrolled who underwent total thyroidectomy and central LN dissection with or without lateral LN dissection in Severance Hospital between October 2013 and July 2015. The study specimens were provided by the Severance Hospital Gene Bank, and consisted of PTC from each patient. The specimens were prepared for proton nuclear magnetic resonance (1H-NMR) spectroscopy. Spectral data by 1H-NMR spectroscopy were acquired, processed, and analyzed. Patients were grouped in three ways, according to the presence of LN metastasis, central LN metastasis and lateral LN metastasis. Chi-square test and the student t-test were used to analyze categorical variables and continuous variables, respectively. The Mann-Whitney U test was used for univariate analysis of metabolites. Orthogonal projections to latent structure discriminant analysis (OPLS-DA) was used for multivariate analysis to discriminate metabolic differences between the two groups.

RESULTS

Among 52 patients, 32 had central LN metastasis and 19 had lateral LN metastasis. No clinical or histopathological characteristic was significantly different for all comparisons. On univariate analysis, no metabolite showed significant difference for all comparisons. On multivariate analysis, OPLS-DA did not discriminate the presence and absence of LN metastasis. Lactate was found to be the most promising metabolite.

CONCLUSIONS

No metabolite could discriminate the presence of LN metastasis. However, lactate was found to be the most promising metabolite for discrimination. Further studies with larger sample sizes are needed to elucidate significant metabolites which can indicate the presence of LN metastasis in patients with PTC.

BRAFV600E mutation as a predictor of thyroid malignancy in indeterminate nodules: A systematic review and meta-analysis

BACKGROUND

Thyroid nodules are usually diagnosed using fine-needle aspiration (FNA). The sensitivity limitations of FNA result in 10-30% of nodules being classified as "indeterminate". The BRAF^V600E mutation is associated with papillary thyroid carcinoma (PTC). We conducted a systemic review and meta-analysis to evaluate the diagnostic utility of the BRAF^V600E mutation in indeterminate nodules.

METHOD

PUBMED and EMBASE were searched for studies testing for the BRAF^V600E involving indeterminate nodules (Thy3a, Thy3f, Thy4) and containing information on final surgical histopathology. Thirty two studies involving 3150 indeterminate nodules were included in the analysis.

RESULTS

The overall sensitivity and specificity for BRAF^V600E for the diagnosis of thyroid malignancy was 0.40 (95% CI: 0.32-0.48) and 1.00 (95% CI: 0.98-1.00) respectively. The diagnostic odds ratio (DOR) was 205.4 (95% CI: 40.1-1052). With a Fagan plot, the post-test probability of thyroid cancer, given a negative mutation was 6%, but this rose to 92% with a positive result. On subgroup analysis, for Thy3a nodules, the pooled sensitivity and specificity for thyroid malignancy was 0.21 (95% CI: 0.13-0.34) and 1.00 (95% CI: 0.98-1.00). For Thy3f nodules, the pooled sensitivity and specificity was 0.09 (95% CI: 0.03-0.20) and 1.00 (95% CI: 0.05-1.00) respectively. For Thy4 nodules, the corresponding sensitivity and specificity was 0.58 (95% CI: 0.5-0.64) and 0.99 (95% CI: 0.95-1.00) respectively.

CONCLUSIONS

Despite a high specificity for thyroid cancer, BRAF^V600E mutation has a low overall sensitivity and therefore has a limited diagnostic value as a single screening test.

Thyroid nodule update on diagnosis and management

Thyroid nodules are common. The clinical importance of thyroid nodules is related to excluding malignancy (4.0 to 6.5% of all thyroid nodules), evaluate their functional status and assess for the presence of pressure symptoms. Incidental thyroid nodules are being diagnosed with increasing frequency in the recent years with the use of newer and highly sensitive imaging techniques. The high prevalence of thyroid nodules necessitates that the clinicians use evidence-based approaches for their assessment and management. New molecular tests have been developed to help with evaluation of malignancy in thyroid nodules. This review addresses advances in thyroid nodule evaluation, and their management considering the current guidelines and supporting evidence.

Novel and Practical Scoring Systems for the Diagnosis of Thyroid Nodules

Objective

The clinical management of patients with thyroid nodules that are biopsied by fine-needle aspiration cytology and yield indeterminate results remains unsettled. The BRAF V600E mutation has dubious diagnostic value due to its low sensitivity. Novel strategies are urgently needed to distinguish thyroid malignancies from thyroid nodules.

Design

This prospective study included 504 thyroid nodules diagnosed by ultrasonography from 468 patients, and fine-needle aspiration cytology was performed under ultrasound guidance. Cytology and molecular analysis, including BRAF V600E, RET/PTC1 and RET/PTC3, were conducted simultaneously. The cytology, ultrasonography results, and mutational status were gathered and analyzed together. Predictive scoring systems were designed using a combination of diagnostic parameters for ultrasonography, cytology and genetic analysis. The utility of the scoring systems was analyzed and compared to detection using the individual methods alone or combined.

Result

The sensitivity of scoring system^a (ultrasonography, cytology, BRAF V600E, RET/PTC) was nearly identical to that of scoring system^b (ultrasonography, cytology, BRAF V600E); these were 91.0% and 90.2%, respectively. These sensitivities were significantly higher than those obtained using FNAC, genetic analysis and US alone or combined; their sensitivities were 63.9%, 70.7% and 87.2%, respectively. Scoring system^c (ultrasonography, cytology) was slightly inferior to the former two scoring systems but still had relatively high sensitivity and specificity (80.5% and 95.1%, respectively), which were significantly superior to those of single cytology, ultrasonography or genetic analysis. In nodules with uncertainty cytology, scoring system^a, scoring system^b and scoring system^c could elevate the malignancy detection rates to 69.7%, 69.7% and 63.6%, respectively.

Conclusion

These three scoring systems were quick for clinicians to master and could provide quantified information to predict the probability of malignant nodules. Scoring system^b is recommended for improving the detection rate among nodules of uncertain cytology.

Follicular and Diffuse Sclerosing Variant Papillary Thyroid Carcinomas as Independent Predictive Factors of Loco-Regional Recurrence: A Comparison Study Using Propensity Score Matching

BACKGROUND

Only about half of papillary thyroid carcinoma (PTC) cases are classified as conventional PTC (CV-PTC), whereas various histologic variants constitute the remaining cases. Since controversies about the clinical behavior and outcomes of PTC variants continue, the purpose of this study was to compare the outcomes of patients with PTC variants who were treated at a large tertiary referral center in Korea.

METHODS

The medical records for 15,598 CV-PTCs, 435 follicular variants of PTC (FV-PTCs), and 66 diffuse sclerosing variants of PTC (DSV-PTCs) were retrospectively reviewed. Loco-regional recurrences (LRR) among PTC variants were compared using propensity score matching.

RESULTS

Analysis I compared CV-PTC with FV-PTC. After rigorous matching, 367 pairs were established. Recurrence-free survival (RFS) rates in CV-PTC were 96.1% at 5 years, 92.2% at 10 years, and 92.2% at 15 years, while those for FV-PTC were 98.8% at 5 years, 98.8% at 10 years, and 98.8% at 15 years (p = 0.026). Analysis II compared CV-PTC with DSV-PTC. Rigorous matching yielded 56 pairs. RFS rates for CV-PTC were 87.4% at 5 years, 87.4% at 10 years, and 87.4% at 15 years, while those for DSV-PTC were 68.9% at 5 years, 57.5% at 10 years, and were not available at 15 years (p = 0.013).

CONCLUSIONS

Compared with CV-PTC, FV-PTC showed less aggressive behaviors and more favorable outcomes. However, DSV-PTC showed more aggressive behaviors and a less favorable outcome than CV-PTC did. Therefore, the management strategy and follow-up plan for PTC should be differentiated according to the histologic variant.

The 5-tiered categorization system for reporting cytology is sufficient for management of patients with thyroid nodules compared to the 6-tiered Bethesda system

To analyze whether the 5-tiered categorization system without the atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) category is sufficient compared to the 6-tiered Bethesda system. This IRB-approved retrospective study was waived informed consent. The pre-Bethesda period was from March 2008 to December 2008 and the Bethesda period was from January 2012 to January 2013. Of 4677 nodules ≥10 mm with initial ultrasonography-guided fine-needle aspiration, 2553 nodules were from the pre-Bethesda period and 1754 nodules were from the Bethesda period. The utilization and malignancy rates of each category were compared between the two periods. The utilization rate of the benign category decreased from 67.7 % in the pre-Bethesda period to 60.0 % in the Bethesda period (p = 0.001). In the pre-Bethesda period, the malignancy rates of the non-diagnostic, benign, suspicious follicular neoplasm/Hürthle cell neoplasm, suspicious for malignancy, and malignancy categories were 3.8, 1.9, 25, 78.8, and 99.7 %, respectively. The malignancy rate of the benign category decreased from 1.9 to 0.3 % after the Bethesda system (p < 0.001). The utilization and malignancy rates of the AUS/FLUS category were 7 and 22.8 %. When the AUS/FLUS category was included in the benign category, the malignancy rate became 2.6 % which was not significantly different from 1.9 % in the pre-Bethesda period (p = 0.189). The malignancy rates of other categories were not significantly different. The 5-tiered categorization system without the AUS/FLUS category for reporting cytology was sufficient for management of patients with thyroid nodules compared to the 6-tiered categorization of the Bethesda system.

Clinical impact of BRAF mutation on the diagnosis and prognosis of papillary thyroid carcinoma: a systematic review and meta-analysis

BACKGROUND

The possible role of BRAF(V) (600E) mutation in the diagnosis and prognosis of papillary thyroid carcinoma (PTC) remains controversial. A systematic review to investigate the diagnostic and prognostic role of BRAF(V) (600E) mutation in patients with PTC is urgently needed.

METHODS

A systematic review of relevant literatures was performed in PubMed, EMBASE and CENTRAL. The incremental accuracy (IA) of fine needle aspiration biopsy plus BRAF(V) (600E) mutation analysis over fine needle aspiration biopsy alone, and the statistical data about the association of BRAF(V) (600E) mutation and the prognosis of PTC (risk ratios (RR) for dichotomous data, standard mean differences for continuous data and hazard ratios (HRs) for disease-free survival (DFS) were pooled. Subgroup analysis was performed to explain the heterogeneities.

RESULTS

A total of 67 studies were included. The pooled IA was 2% (95% confidence interval (CI): 0·5-4%). The pooled RR for gender, multifocality, lymph node metastasis, extrathyroidal invasion and pathological stage was 1·11 (95% CI: 0·98-1·25), 1·17 (95% CI: 1·09-1·24), 1·36 (95% CI: 1·20-1·53), 1·60 (95% CI: 1·41-1·82), and 1·49 (95% CI: 1·33-1·68), respectively. The pooled standard mean differences for age and tumour size were 0·14 (95% CI: 0·04-0·23) and 0·21 (95% CI: 0·1-0·32), respectively. The pooled HR for DFS was 1·96 (95% CI: 1·62-2·37). Subgroup analysis showed that these statistical results were affected by the geographical background of patients, study design and detection methods.

CONCLUSIONS

BRAF(V) (600E) mutation analysis can not only be used in the diagnosis of PTC, but can also predict its prognosis.

2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

BRAF V600E mutation: Differential impact on central lymph node metastasis by tumor size in papillary thyroid carcinoma

BACKGROUND

The necessity of prophylactic central neck dissection is one of debating issues in the treatment of papillary thyroid carcinoma (PTC). In a previous study, the predictive value of BRAF mutation for lymph node metastasis was only significant in 0.5 to 1.0 cm PTC. Thus, we assess the predictive value of BRAF mutation for central lymph node metastasis according to tumor size.

METHODS

Medical records of 3107 patients with PTC who underwent thyroidectomy with central neck dissection were retrospectively reviewed.

RESULTS

BRAF mutation was a predictor for central lymph node metastasis in 2.0 to 4.0 cm PTC (odds ratio [OR] = 3.494; p = .002). Although BRAF mutation was associated with central lymph node metastasis in 0.5 to 1.0 cm PTC in univariate analysis (OR = 1.334; p = .047), this significance was not observed in multivariate analysis (OR = 1.232; p = .163). BRAF mutation was not associated with central lymph node metastasis in other tumor sizes.

CONCLUSION

Prophylactic central neck dissection could be considered in 2.0 to 4.0 cm PTC with positive BRAF mutation. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1203-E1209, 2016.

Cytomorphologic features in thyroid nodules read as "suspicious for malignancy" on cytology may predict thyroid cancers with the BRAF mutation

Some morphologic parameters have been studied to help predict the BRAF(V600E) mutation using cytopathologic specimens, which can indicate which nodules should undergo further testing. The aim of this study was to investigate the value of cytomorphologic parameters to predict the BRAF(V600E) mutation in nodules read as "suspicious for malignancy" on cytology. This study included 142 resected nodules which were diagnosed as "suspicious for malignancy" on cytology in 142 patients. At our institution, BRAF(V600E) mutation analysis was performed at the request of the referring clinicians based on the clinical features of the patients, or the judgment of the radiologists performing US-FNA because suspicious US features were observed on the targeted nodule during this study period. Cytology smears were re-reviewed to assess the presence and amount of polygonal eosinophilic (plump) cells and microfollicles, and the presence of intranuclear pseudoinclusions, irregular nuclear membranes, nuclear grooves, sickles cells, psammoma bodies, and cystic changes. We evaluated the diagnostic performances of the cytomorphologic features to predict the BRAF(V600E) mutation. Polygonal eosinophilic (plump) cells, microfollicles, intranuclear pseudoinclusions, sickle cells, and cystic changes were significantly associated with the BRAF(V600E) mutation. The mutation was not present in all 6 thyroid nodules with microfollicles larger than 20% on cytology. Additionally, polygonal eosinophilic (plump) cells larger than 20%, cystic changes, and sickle cells on cytology had a high specificity of 95%, 96.7%, and 81.7%, respectively. Excluding 6 nodules with microfollicles larger than 20% on cytology, there were 82 (60.3%) nodules with the BRAF(V600E) mutation among the 136 nodules. Among the 136 nodules, there were 95 nodules with polygonal eosinophilic (plump) cells larger than 20%, cystic changes, or sickle cells on cytology. Of the 95 nodules, 69 (72.6%) had the mutation. Cytomorphologic features can help select nodules for the BRAF(V600E) mutation test among nodules read as "suspicious for malignancy" on cytology.

Prediction Table and Nomogram as Tools for Diagnosis of Papillary Thyroid Carcinoma: Combined Analysis of Ultrasonography, Fine-Needle Aspiration Biopsy, and BRAF V600E Mutation

Although ultrasonography (US)-guided fine-needle aspiration biopsy (FNAB) is the most reliable diagnostic modality for evaluating thyroid nodules, 10% to 40% of FNAB samples yield indeterminate findings. The BRAF V600E mutation, a highly specific molecular marker for papillary thyroid carcinoma (PTC), well known for its prognostic value, has dubious diagnostic value because of its low sensitivity. Novel strategies are clearly needed to distinguish PTC, which represents the majority of thyroid malignancies, from other thyroid nodules. The records of 3297 patients with surgically proven PTC were retrospectively reviewed. A prediction table and nomogram were designed using a combination of diagnostic parameters for US, FNAB, and the BRAF V600E mutation. For the nomogram, parameters were proportionally assigned 0 to 100 points according to their regression coefficient for PTC. The probability of PTC for thyroid nodules with intermediate-risk (IR) US and atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) FNAB was significantly dependent on BRAF V600E mutation status based on our prediction table (negative, 29.2% vs positive, 87.5%; P < 0.001). By our nomogram, the probability of PTC for thyroid nodules with IR US, AUS/FLUS FNAB, and positive BRAF V600E mutation was approximately 85% to 90%. We strongly recommend preoperative evaluation of the BRAF V600E mutation in indeterminate thyroid nodules. The prediction table and nomogram developed in this study could help clinicians and patients easily assess the probability of PTC in the preoperative period.

Role of BRAF molecular analysis in the management of papillary thyroid carcinoma: analysis of cytological and histological samples

BACKGROUND

Although fine needle aspiration (FNA) is the standard diagnostic test for the characterization of a suspicious thyroid nodule, in some cases cytological evaluation is inconclusive. The aim of this study was to determine the role of BRAF mutation in aiding diagnosis and to verify whether archival cytological samples could be suitable for molecular analysis.

METHODS

Eighty-five patients with suspicious (Thy4) or follicular (Thy3) lesions on cytology were resubmitted to a second FNA for BRAF mutation analysis. Of these, 56 subsequently underwent surgery. The usefulness of archival samples for molecular analysis was also studied in a second cohort of 42 patients with a confirmed diagnosis of papillary thyroid carcinoma for whom both archived paraffin-embedded histological samples and cytological smears were available. A further 15 patients with paired fresh FNA and archived cytological and histological samples were recruited.

RESULTS

BRAF mutation was found in the fresh FNA samples from 10 of 56 patients who had surgery with previous inconclusive cytology (4/45, 9%, Thy3 and 6/11, 55%, Thy4). The BRAF test showed a specificity and positive predictive value of 100% (26/26 and 10/10, respectively), sensitivity of 33% (10/30) and negative predictive value of 57% (26/46). There was absolute concordance between the BRAF results obtained with 42 histological and cytological archived samples. BRAF analysis on 15 archived cytological samples showed absolute concordance with histology, whereas there was one false negative on the matched fresh FNA.

CONCLUSION

BRAF analysis is a highly specific test that can facilitate cytological diagnosis in some cases and can also be performed on archived cytological samples.

Molecular diagnostics of fine needle aspiration for the presurgical screening of thyroid nodules

"The incidence of thyroid cancer, the most common endocrine malignancy, is rising. The two most common types of thyroid cancer are papillary and follicular" thyroid carcinomas. "Fine-needle aspiration (FNA) of thyroid nodules" can permit to detect many genetic mutations and other molecular alterations, including RAS and BRAF point mutations, PAX8/peroxisome proliferator-activated receptor (PPAR)γ and "RET/PTC rearrangements, occurring in thyroid papillary and follicular carcinomas" (more than 70% of cases), which can be used successfully to improve the diagnosis "and the management of patients with thyroid nodules". The most extensive experience has been accumulated with "the diagnostic use of BRAF mutation", which is highly specific for malignancy. "Testing FNA samples for a panel of mutations" that typically includes RAS, BRAF, PAX8/PPARγ and RET/PTC could permit to achieve the biggest diagnostic impact. "The accuracy of cancer diagnosis in thyroid nodules could be improved significantly using these and other emerging molecular markers".

Contribution of the BRAF oncogene in the pre-operative phase of thyroid carcinoma

Numerous experiments have been conducted over the last few years aiming to identify molecular markers that show the diagnostic accuracy of fine-needle aspiration (FNA), particularly in thyroid lesions that are considered indeterminate. Using certain search arguments and previously defined criteria, 37 studies reporting experiments with the BRAF mutation in pre-operative FNA of the thyroid were selected from the electronic databases PUBMED, MEDLINE, SCOPUS and LILACS, in order to gather evidence with regard to the possible contribution of BRAF in the management of thyroid carcinoma. There were no cases positive for BRAF in follicular carcinomas (FTCs), Hürthle cell carcinomas (HCCs) or medullary thyroid carcinomas (MTCs). Among the 11 cases of anaplastic thyroid carcinomas (ATC), three showed positive results for the BRAF mutation. The number of cases positive for BRAF among the benign lesions was not significant. The average prevalence of BRAF-positive cases in papillary carcinomas (PTC) was 58.6%, while in follicular variants of papillary carcinoma (FVPTC), the average prevalence was 29.6%. For lesions diagnosed as indeterminate or suspicious, the average prevalence of BRAF positivity in PTC was 48.5%. The experiments included in the present study indicated a specificity of almost 100% and a high predominance of the BRAF mutation in PTC, distinguishing the marker in the planning and medical management of papillary carcinoma of the thyroid.

Is follow-up BRAF(V600E) mutation analysis helpful in the differential diagnosis of thyroid nodules with negative results on initial analysis?

Background

We evaluated the usefulness of follow-up BRAF^V600E mutation analysis using ultrasonography-guided fine-needle aspiration (US-FNA) in diagnosis of thyroid nodules showing negative BRAFV600E mutation on prior analysis.

Methodology/Principal Finding

A total of 49 patients (men: 6, women: 43, mean age: 50.4 years) with 49 thyroid nodules were included. Patients had undergone initial and follow-up US-FNA and subsequent BRAF^V600E mutation analysis from US-FNA aspirates. All patients had negative results on initial BRAF^V600E mutation analysis. Clinicopathologic findings, US assessment, and BRAF^V600E mutation results were analyzed according to the final pathology. Of the 49 nodules, 12 (24.5%) were malignant and 37 (75.5%) were benign. Seven (58.3%) of the 12 malignant nodules were positive for BRAF^V600E mutation on follow-up, all showing suspicious US features. Initial US-FNA cytology of the 7 nodules were non-diagnostic (n = 2), benign (n = 2), or atypia (n = 3), while follow-up were benign (n = 1), indeterminate (n = 1), suspicious for malignancy (n = 4), and malignancy (n = 1).

Conclusions/Significance

Follow-up BRAF^V600E mutation analysis may be helpful in the diagnosis of selected thyroid nodules negative for BRAF^V600E mutation on initial analysis, which are assessed as suspicious malignant on US, diagnosed as non-diagnostic, benign or atypia on follow-up US-FNA.

Sensitive electrochemical analysis of BRAF V600E mutation based on an amplification-refractory mutation system coupled with multienzyme functionalized Fe3O4/Au nanoparticles

A novel electrochemical biosensor was developed for the analysis of BRAF V600E mutation in colorectal cancer cell samples based on a dual amplification strategy of amplification-refractory mutation system (ARMS) PCR and multiple enzyme labels. The labeled amplicons were conjugated on Fe3O4/Au nanoparticles using Au-S linkages. Alkaline phosphatases were then loaded onto the nanoparticles through biotin-streptavidin interactions. The resultant composite nanoparticles were characterized by transmission electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry. In the presence of 2-phospho-l-ascorbic acid, the mutant alleles were quantified on a screen-printed carbon electrode (SPCE) from the anodic current of the enzymatic product, ascorbic acid. BRAF V600E mutant alleles concentrations as low as 0.8% were successfully determined in an excess of wild-type background. In a cell-line dilution model, the proposed method was more sensitive than were DNA sequencing and agarose gel electrophoresis. This work demonstrates a new strategy for sensitivly detecting BRAF V600E variations. It can pave the way for analyzing other rare mutations in complex cancer samples because of its high sensitivity, simplicity, low cost, and easy validation of assay procedures.

Study of peripheral BRAF(V600E) mutation as a possible novel marker for papillary thyroid carcinomas

BACKGROUND

The BRAF(V600E) mutation can be detected peripherally in the serum of patients with thyroid cancer. The purpose of this study was to establish the value of detecting the peripheral BRAF(V600E) mutation as a serum tumor marker in this population.

METHODS

In this study, we obtained 94 serum samples from patients with papillary thyroid cancer positive for the BRAF(V600E) mutation in the tumor itself. The serum samples were analyzed for BRAF(V600E) mutation using real-time polymerase chain reaction (PCR).

RESULTS

Sixty-seven patients (71.3%) had papillary thyroid microcarcinoma and 26 patients (27.7%) had underlying lymphocytic thyroiditis. Forty-three patients (45.7%) were found to have stage III or stage IV thyroid cancer. None of the patients had a detectable serum BRAF(V600E) mutation.

CONCLUSION

We were unable to identify peripheral BRAF(V600E) mutations in patients with papillary thyroid cancer using real-time PCR. Further studies will be needed to validate our results using various diagnostic methods.

Reduction of false-negative papillary thyroid carcinomas by the routine analysis of BRAF(T1799A) mutation on fine-needle aspiration biopsy specimens: a prospective study of 814 thyroid FNAB patients

OBJECTIVES

To evaluate prospectively the usefulness of the routine determination of BRAF(T1799A) mutation on thyroid fine-needle aspiration biopsy (FNAB) to detect cytopathology false negative papillary thyroid carcinomas (PTC) and, therefore, as a tool to improve the sensitivity of the preoperative cytopathological diagnosis of PTC in thyroid nodules.

BACKGROUND

FNAB is the most reliable diagnostic test to discriminate between malignant and benign thyroid nodules, but nondiagnostic results remain a clinical management dilemma. BRAF(T1799A) mutation is the most prevalent genetic alteration in thyroid cancers and is specific for PTC, characteristics that make it the most potentially helpful genetic tool to improve the diagnostic accuracy of FNAB.

METHODS

An exhaustive recruitment of all patients subjected to thyroid FNAB in our institution during 4 years was performed. BRAF(T1799A) mutation was determined on thyroid FNAB specimens by PCR and restriction fragment length polymorphism, plus direct sequencing in positive samples.

RESULTS

BRAF(T1799A) mutation on FNAB detected 47.2% (17/36) of PTC cases. It confirmed preoperatively 45.5% (5/11) of the PTC cases in the indeterminate category and decreased the rate of cytopathology false-negatives in 33.3% (6/18), improving the combined (BRAF(T1799A) mutation + cytopathological analysis) sensitivity of the detection of PTC on FNAB in 16.7%.

CONCLUSIONS

BRAF(T1799A) mutation improves the diagnosis of PTC on FNAB, mainly because of the detection of cytopathology false-negatives, and it can be helpful in the routine analysis of thyroid nodules, especially in clinical settings with moderate sensitivity to detect PTC on FNAB.

High Prevalence of B-RAF Mutation in Papillary Carcinoma of the Thyroid in North-East Italy

B-RAF V600E mutation is frequently observed in several tumors, including papillary thyroid carcinomas (PTCs), where it is considered of potential diagnostic and prognostic value. The reported prevalence of B-RAF mutation in PTCs in different Italian populations varies from 14% to 69%. The authors investigate the prevalence and utility of the B-RAF V600E mutation in a series of 91 fine needle aspiration biopsies (FNABs) of the thyroid and in 60 histologically proven PTCs in a well-defined north Italian population. In their series, the B-RAF mutation was detected in 43 (72%) PTCs and was more frequent in classic (34 out of 44, 77%) versus variant follicular PTCs (PTCVF; 9 out of 16, 56%). In all, 41 (46%) FNABs showed B-RAF mutation and corresponded to histologically proven PTCs (33 classic type and 8 PTCVF), which had been cytologically classified as malignant (28 cases), atypical/suspicious (10), inadequate (1), and benign (2). B-RAF mutations were never seen in non-PTC/ PTCVF FNAB cases, implying a 100% positive predictive value.These data demonstrate a high prevalence of B-RAF mutations in the present study population, underscoring the possibility of strong regional differences in B-RAF mutation prevalence in PTCs and further confirming its high diagnostic value on FNAB.

Impact of proto-oncogene mutation detection in cytological specimens from thyroid nodules improves the diagnostic accuracy of cytology

CONTEXT

Fine-needle aspiration cytology (FNAC) is the gold standard for the differential diagnosis of thyroid nodules but has the limitation of inadequate sampling or indeterminate lesions.

OBJECTIVE

We aimed to verify whether search of thyroid cancer-associated protooncogene mutations in cytological samples may improve the diagnostic accuracy of FNAC.

STUDY DESIGN

One hundred seventy-four consecutive patients undergoing thyroid surgery were submitted to FNAC (on 235 thyroid nodules) that was used for cytology and molecular analysis of BRAF, RAS, RET, TRK, and PPRgamma mutations. At surgery these nodules were sampled to perform the same molecular testing.

RESULTS

Mutations were found in 67 of 235 (28.5%) cytological samples. Of the 67 mutated samples, 23 (34.3%) were mutated by RAS, 33 (49.3%) by BRAF, and 11 (16.4%) by RET/PTC. In 88.2% of the cases, the mutation was confirmed in tissue sample. The presence of mutations at cytology was associated with cancer 91.1% of the times and follicular adenoma 8.9% of the time. BRAF or RET/PTC mutations were always associated with cancer, whereas RAS mutations were mainly associated with cancer (74%) but also follicular adenoma (26%). The diagnostic performance of molecular analysis was superior to that of traditional cytology, with better sensitivity and specificity, and the combination of the two techniques further contributed to improve the total accuracy (93.2%), compared with molecular analysis (90.2%) or traditional cytology (83.0%).

CONCLUSIONS

Our findings demonstrate that molecular analysis of cytological specimens is feasible and that its results in combination with cytology improves the diagnostic performance of traditional cytology.