High-Resolution Melting Is a Sensitive, Cost-Effective, Time-Saving Technique for BRAF V600E Detection in Thyroid FNAB Washing Liquid: A Prospective Cohort Study

Deciphering the progression of fine-needle aspiration: A bibliometric analysis of thyroid nodule research

This study aims to dissect the evolution and pivotal shifts in Fine-Needle Aspiration (FNA) research for thyroid nodules over the past 2 decades, focusing on delineating key technological advancements and their impact on clinical practice. A comprehensive bibliometric analysis was conducted on 5418 publications from the Web of Science Core Collection database (2000-2023). Publications were rigorously selected based on their contributions to the advancement of FNA techniques and their influence on thyroid nodule management practices. Our analysis uncovered significant breakthroughs, most notably the incorporation of ultrasound and molecular diagnostics in FNA, which have markedly elevated diagnostic accuracy. A pivotal shift was identified towards minimally invasive post-FNA treatments, such as Radiofrequency Ablation, attributable to these diagnostic advancements. Additionally, the emergence of AI-assisted cytology represents a frontier in precision diagnostics, promising enhanced disease identification. The geographical analysis pinpointed the United States, Italy, and China as key contributors, with the United States leading in both publication volume and citation impact. This bibliometric analysis sheds light on the transformative progression in FNA practices for thyroid nodules, characterized by innovative diagnostic technologies and a trend towards patient-centric treatment approaches. The findings underscore the need for further research into AI integration and global practice standardization. Future explorations should focus on the practical application of these advancements in diverse healthcare settings and their implications for global thyroid nodule management.

Value of repeated US-guided fine-needle aspiration (US-FNAB) in the follow-up of benign thyroid nodules: a real-life study based on the MoCyThy (Modena's Cytology of the Thyroid) DATABASE with a revision of the literature

PURPOSE

The utility of repeating ultrasound-guided fine-needle aspiration (US-FNAB) in the follow-up of benign (THY2) thyroid nodules is still debated. The aim of this study was to retrospectively investigate the diagnostic value of re-biopsy of thyroid nodules following an initially benign result.

METHODS

We retrospectively analyzed US-FNABs performed at the Unit of Endocrinology of Modena from 2006 to 2009. The firstly benign cytological result was compared with the cytological results of subsequent US-FNABs (2nd and/or 3rd) executed on the same nodule.

RESULTS

Among 10449 US-FNABs, 6270 (60%) received a THY2 cytological categorization. Of them, 278 (4.43%) underwent a subsequent US-FNAB: 86.7% maintained the same cytology, 32 (11.5%) changed to THY3 (indeterminate) and 5 (1.8%) to THY4 (suspicious of malignancy). Among the 24 nodules addressed to surgery, 9 (37%) were histologically malignant, with an overall miss rate of 3.2%. Male patients had higher risk of discordant results at subsequent US-FNAB (p = 0.005, OR:3.59, 95%CI:1.453-7.769) while dimensional increase above 5 mm was predictive of concordant benign cytology (p = 0.036, OR:0.249, 95%CI:0.068-0.915). Age, suspicious US characteristics, and distance between US-FNABs resulted not predictive.

CONCLUSIONS

Re-biopsy of benign nodules confirmed the benign nature in most cases. In case of discordant cytology, relocation in indeterminate category was the most common. The histological diagnosis of cancer occurred in one quarter of nodules surgically removed, with a low overall clinically significant miss rate. Thus, a small percentage of false negatives exists; males and subjects with US suspicious nodules should be carefully followed-up, considering case by case re-biopsy possibility.

BRAFV600E mutation test on fine-needle aspiration specimens of thyroid nodules: Clinical correlations for 4600 patients

Background

The BRAF^V600E mutation is valuable for the diagnosis, prognosis, and therapy of papillary thyroid cancer (PTC). However, studies related to this mutation have involved only a small number of patients. Therefore, we performed a large‐scale analysis from a single institute to evaluate the accuracy of combined fine‐needle aspiration (FNA) and BRAF^V600E mutation tests for PTC diagnosis.

Methods

A total of 4600 patients with thyroid nodules who underwent both FNA cytology and BRAF^V600E mutation analysis on FNA specimens were enrolled. The association between the BRAF^V600E mutation and clinicopathological features was analyzed. A separate analysis was performed for the 311 patients who underwent repeated FNA for comparison of cytological evaluation and BRAF^V600E mutation results. The diagnostic efficacy of the BRAF^V600E mutation test and cytologic diagnoses was evaluated for 516 patients who underwent preoperative FNA tests in comparison with conclusive postoperative histopathologic results.

Results

The cytology results of all 4600 FNA samples were categorized according to The Bethesda System for Reporting Thyroid Cytology (TBSRTC) stages I–VI, which accounted for 11.76%, 60.02%, 6.46%, 3.61%, 6.71%, and 11.43% of the samples, respectively. The BRAF^V600E mutation was detected in 762 (16.57%) FNA samples, with rates of 1.48%, 0.87%, 20.20%, 3.01%, 66.02%, and 87.81% for TBSRTC I–VI lesions, respectively. Among the 311 repeat FNA cases, 81.0% of the BRAF^V600E‐positive and 4.3% of the BRAF^V600E‐negative specimens with an initial indication of cytological non‐malignancy were ultimately diagnosed as malignant by repeat FNA (p < 0.001). Among the 516 patients who underwent thyroidectomy, the sensitivity and specificity of the BRAF^V600E mutation test alone for PTC diagnosis were 76.71% and 100.0%, respectively, which increased to 96.62% and 88.03%, respectively, when combining the BRAF^V600E mutation test with cytology. BRAF^V600E mutation was significantly associated with lymph node metastasis (p < 0.001), but not with age, gender, or tumor size.

Conclusions

The BRAF^V600E mutation test in FNA samples has potential to reduce false negatives in PTC diagnosis, and therefore plays an important role in the diagnosis of thyroid nodules, especially those with an indeterminate or nondiagnostic cytology, which should be considered for repeat FNA.

Real-life use of BRAF-V600E mutation analysis in thyroid nodule fine needle aspiration: consequences on clinical decision-making

PURPOSE

This study aimed to evaluate the real-life use of BRAF-V600E mutation analysis in washout liquid from thyroid nodule fine needle aspiration (FNA), and the consequences of genetic result on clinical decision-making.

METHODS

We retrospectively considered subjects tested for BRAF-V600E among those attending the Endocrinology Unit of Modena for FNA between 2014 and 2018. Washing fluid was collected together with cytological sample and stored at -20 °C. If the clinician deemed it necessary, the sample was thawed, DNA extracted, and genetic test performed by high-resolution melting technique. We collected data on cytology according to the Italian Consensus for the cytological classification of thyroid nodules, type of surgery (when performed), histology, and adverse events.

RESULTS

Out of 7112 subjects submitted to FNA, BRAF analysis was requested for 683 (9.6%). Overall, 896 nodules were analyzed: 74% were indeterminate at cytology, mainly TIR3A (low risk). Twenty-two nodules were mutant (BRAF+). Only 2% of indeterminate, mainly TIR3B, were BRAF+. Based on final histological diagnosis, BRAF test had high specificity (100%) but poor sensitivity (21%), also in indeterminate nodules. Mutant subjects underwent more extensive surgery compared to wild type (p = 0.000), with frequent prophylactic central lymph node dissection. One third had local metastases. Higher prevalence of hypoparathyroidism was found in BRAF+ compared to wild type (p = 0.018).

CONCLUSIONS

The analysis of BRAF-V600E outside of gene panels has low sensitivity, especially in indeterminate nodules, and a positive result could lead to more extensive surgery with greater risk of hypoparathyroidism and questionable clinical utility.

Molecular markers for the classification of cytologically indeterminate thyroid nodules

BACKGROUND

The diagnosis of indeterminate lesions of the thyroid is a challenge in cytopathology practice. Indeed, up to 30% of cases lack the morphological features needed to provide definitive classification. Molecular tests have been developed to assist in the diagnosis of these indeterminate cases. The first studies dealing with the preoperative molecular evaluation of FNA samples focused on the analysis of BRAF^V600E or on the combined evaluation of two or three genetic alterations. The sensitivity of molecular testing was then improved through the introduction of gene panels, which became available for clinical use in the late 2000s. Two different categories of molecular tests have been developed, the 'rule-out' methods, which aim to reduce the avoidable treatment of benign nodules, and the 'rule-in' tests that have the purpose to optimize surgical management. The genetic evaluation of indeterminate thyroid nodules is predicted to improve patient care, particularly if molecular tests are used appropriately and with the awareness of their advantages and weaknesses. The main disadvantage of these tests is the cost, which makes them rarely used in Europe. To overcome this limitation, customized panels have been set up, which are able to detect the most frequent genetic alterations of thyroid cancer.

CONCLUSIONS

In the present review, the most recent available versions of commercial molecular tests and of custom, non-commercial panels are described. Their characteristics and accuracy in the differential diagnosis of indeterminate nodules, namely Bethesda classes III (Atypical follicular lesion of undetermined significance, AUS/FLUS) and IV (Suspicious for follicular neoplasm, FN/SFN) are fully analyzed and discussed.

Molecular Variants and Their Risks for Malignancy in Cytologically Indeterminate Thyroid Nodules

Background: Gene panels are routinely used to assess predisposition to hereditary cancers by simultaneously testing multiple susceptibility genes and/or variants. More recently, genetic panels have been implemented as part of solid tumor malignancy testing assessing somatic alterations. One example is targeted variant panels for thyroid nodules that are not conclusively malignant or benign upon fine-needle aspiration (FNA). We systematically reviewed published studies from 2009 to 2018 that contained genetic data from preoperative FNA specimens on cytologically indeterminate thyroid nodules (ITNs) that subsequently underwent surgical resection. Pooled prevalence estimates per gene and variant, along with their respective positive predictive values (PPVs) for malignancy, were calculated. Summary: Our systematic search identified 540 studies that were supplemented by 18 studies from bibliographies or personal files. Sixty-one studies met all inclusion criteria and included >4600 ITNs. Overall, 26% of nodules contained at least 1 variant or fusion. However, half of them did not include details on the specific gene, variant, and/or complete fusion pair reported for inclusion toward PPV calculations. The PPVs of genomic alterations reported at least 10 times were limited to BRAF^V600E (98%, 95% confidence interval [CI 96-99%]), PAX8/PPARG (55% [CI 34-78%]), HRAS^Q61R (45% [CI 22-72%]), BRAF^K601E (42% [CI 19-68%]), and NRAS^Q61R (38% [CI 23-55%]). Excluding BRAF^V600E, the pooled PPV for all other specified variants and fusions was 47%. Multiple variants within the same nodule were identified in ∼1% of ITN and carried a cumulative PPV of 77%. Conclusions: The chance that a genomic alteration predicts malignancy depends on the individual variant or fusion detected. Only five alterations were reported at least 10 times; BRAF^V600E had a PPV of 98%, while the remaining four had individual PPVs ranging from 38% to 55%. The small sample size of most variants and fusion pairs found among ITNs, however, limits confidence in their individual PPV point estimates. Better specific reporting of genomic alterations with cytological category, histological subtype, and cancer staging would facilitate better understanding of cancer prediction, and the independent contribution of the genomic profile to prognosis.

The use of high-resolution melting techniques for mutation screening of diseases caused by trinucleotide repeats expansion, with emphasis on the <em> AR </em> gene

BACKGROUND Trinucleotide repeat expansion (TRE) diseases are genetic diseases caused by an increase in the number of CAG, CGG, and CTG codons. CAG repeat expansion in exon 1 of the androgen receptor (AR) gene is known to be associated with disorders of sex development (DSD) and spinal and bulbar muscular atrophy (SBMA). Because the traditional Southern blot for CAG repeat expansion is laborious and time-consuming, this study was aimed to use high-resolution melting (HRM) analysis to screen the CAG repeat length of the AR gene in Indonesian patients with DSD. METHODS In total, 30 male patients with DSD (46, XY), one male patient with SBMA, and 30 healthy males (control) were included in the study. The CAG repeat length was determined using HRM analysis, and Sanger sequencing was used to confirm the CAG repeat length. RESULTS For the DSD cases and controls, the melting temperature (Tm) was within the normal range of 89–91.05°C; however, Tm was 92.65°C for the SBMA case. Sanger sequencing confirmed that DSD cases had 13–27 CAG repeats, and the SBMA case had 54 CAG repeats. CONCLUSIONS HRM analysis using polymerase chain reaction is a sensitive, effective, and rapid technique for screening CAG repeat expansion in exon 1 of the AR gene. This is the first technique for AR gene screening that may be applicable to other TRE diseases.

High-resolution melting analysis for rapid and sensitive MYD88 screening in chronic lymphocytic leukemia

High resolution melting (HRM) assay is a novel technology for the fast, high-throughput, sensitive, post-PCR analysis of genetic mutations. Myeloid differentiation primary response 88 (MYD88) mutations are frequently reported in chronic lymphocytic leukemia (CLL) and confer a worse prognosis. The objective of the present study was to assess the value of HRM analysis for the rapid screening of MYD88 mutations in patients with CLL. Genomic DNA samples were extracted from the bone marrow of 129 newly diagnosed patients with CLL. A plasmid with an MYD88-L265P mutation was constructed, and the p.L265P substitution, which is the predominant MYD88 mutation in CLL, was detected using HRM analysis and direct sequencing. The plasmid pCMV-MYD88-L265P-Mu was successfully constructed as a positive control, and was verified by direct sequencing. The normalized and shifted melting curves of 6/129 (4.65%) samples were clearly different from those of other patients by HRM analysis. In addition, the 794T>C mutation in MYD88 was identified in 6 (4.65%) patients by direct sequencing. Sensitivity evaluation revealed that the HRM assay had a higher sensitivity (to 1% dilution) than direct sequencing, in addition to being convenient and time-saving. The MYD88 p.L256P mutation has been implicated to be associated with adverse prognosis in CLL. HRM analysis has the potential to be a routine prescreening technique to identify the MYD88 p.L256P mutation and may facilitate the clinical treatment of CLL.

Diagnostic Utility of Molecular and Imaging Biomarkers in Cytological Indeterminate Thyroid Nodules

Indeterminate thyroid cytology (Bethesda III and IV) corresponds to follicular-patterned benign and malignant lesions, which are particularly difficult to differentiate on cytology alone. As ~25% of these nodules harbor malignancy, diagnostic hemithyroidectomy is still custom. However, advanced preoperative diagnostics are rapidly evolving.This review provides an overview of additional molecular and imaging diagnostics for indeterminate thyroid nodules in a preoperative clinical setting, including considerations regarding cost-effectiveness, availability, and feasibility of combining techniques. Addressed diagnostics include gene mutation analysis, microRNA, immunocytochemistry, ultrasonography, elastosonography, computed tomography, sestamibi scintigraphy, [18F]-2-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET), and diffusion-weighted magnetic resonance imaging.The best rule-out tests for malignancy were the Afirma® gene expression classifier and FDG-PET. The most accurate rule-in test was sole BRAF mutation analysis. No diagnostic had both near-perfect sensitivity and specificity, and estimated cost-effectiveness. Molecular techniques are rapidly advancing. However, given the currently available techniques, a multimodality stepwise approach likely offers the most accurate diagnosis, sequentially applying one sensitive rule-out test and one specific rule-in test. Geographical variations in cytology (e.g., Hürthle cell neoplasms) and tumor genetics strongly influence local test performance and clinical utility. Multidisciplinary collaboration and implementation studies can aid the local decision for one or more eligible diagnostics.

High-resolution melting analysis for rapid and sensitive NOTCH1 screening in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a biological and clinical heterogeneous disease. Activating mutations of NOTCH1 have been implicated to be associated with adverse prognosis in CLL. The objective of the present study was to develop an effective high-resolution melting (HRM) assay for detecting NOTCH1 mutations. Genomic DNA (gDNA) extracted from 133 CLL patients was screened by HRM assay, and the results were compared with the data obtained using direct sequencing. The relative sensitivity of the HRM assay and direct sequencing was evaluated using diluted gDNA with different NOTCH1 mutational frequencies. The HRM assay was able to detect and discriminate samples with NOTCH1 mutations from the wild-type template in CLL. Eight of the 133 CLL patients (6.02%) were scored positively for NOTCH1 mutations in the HRM assay. The results of the NOTCH1 mutations detected by HRM analysis achieved 100% concordance with those determined from direct sequencing. HRM had a higher sensitivity (1%) and shorter turn-around time (TAT), compared to direct sequencing. In conclusion, the HRM assay developed by us was confirmed to be a rapid, sensitive, and promising approach for high-throughput prognostic NOTCH1 screening in CLL. It enables real-time NOTCH1 evaluation, which is of great significance in clinical practice and may facilitate the decision-making of clinicians in CLL.