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

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.

The value of Korean, American, and Chinese ultrasound risk stratification systems combined with BRAF(V600E) mutation for detecting papillary thyroid carcinoma in cytologically indeterminate thyroid nodules

PURPOSE

To investigate the value of Korean, American, and Chinese ultrasound risk stratification systems combined with BRAF(V600E) mutation in the detection of papillary thyroid carcinoma (PTC)within cytologically indeterminate thyroid nodules (CITNs).

METHODS

A single-center retrospective study encompassed 511 CITNs selected from 509 patients between January 2020 and July 2023.Each nodule underwent surgical treatment and was classified according to three distinct systems. Receiver operating characteristic (ROC) curves were plotted using histopathological diagnosis as the reference standard, and diagnostic performance was compared.

RESULTS

The three ultrasound stratification systems showed an elevated malignant risk with increasing grades (all P for trend2 < 0.001). The cut-off values for Korean, American, and Chinese systems were 5, 5, and 4c, and their respective area under the curves (AUCs) were 0.735, 0.778, and 0.783.The combination of BRAF (V600E) mutation significantly enhanced the diagnostic efficacy for the Korean(0.773vs0.735, P < 0.001), American (0.809vs0.778, P < 0.001) and Chinese (0.815vs0.783, P < 0.001) stratification systems in distinguishing CITNs without compromising specificity. When the three stratification systems were applied individually or combined with BRAF (V600E) mutation, the AUCs of the American and Chinese systems were similar (all P > 0.05), both of which were higher than the AUC of the Korean system (all P < 0.05). The American system exhibited higher specificity compared to the Chinese and Korean systems (all P < 0.001), whereas the Chinese system demonstrated higher sensitivity and accuracy when compared to the American and Korean systems (all P < 0.001).

CONCLUSION

Korean, American and Chinese stratification systems present potential in the differential diagnosis of CITNs. BRAF (V600E) mutation can significantly improve the detection rate of malignant nodules within CTNs, particularly PTC. Notably, the American and Chinese systems demonstrate superior overall diagnostic performance among these systems.

[Molecular and other ancillary tests proposed by The Bethesda system for reporting thyroid cytopathology 2023]

For the first time the 2023 version of The Bethesda System for Reporting Thyroid Cytology dedicates a whole chapter (chapter 14) to ancillary studies almost exclusively represented by molecular testing. The latest data reported bring some evidence that molecular testing could help to optimize the diagnostic performance of « indeterminate » categories (AUS and NF). Other studies suggest a promising role to guide the management of suspicious of malignancy and malignant categories. Indeed, the recognition of prognostic and predictive biomarkers analyzed on cytological samples, regardless of how it is collected, has progressed thanks to advances in our knowledge of molecular abnormalities of thyroid tumors. The chapter 14 is presented here highlighting the current and emerging roles of « in-house » and commercialized molecular testing as presented by TSBRTC.

Diagnostic Value and Challenges of BRAF V600E Molecular Testing and Thyroid Fine-Needle Aspiration Cytology: A Retrospective Study from a Tertiary Institution in Southern Hunan Province, China

INTRODUCTION

Combined thyroid fine-needle aspiration (FNA) cytology and valine-to-glutamate substitution at codon 600 of B-Raf proto-oncogene, serine/threonine kinase (BRAF V600E) mutation detection are procedures used for diagnosing thyroid nodules in many Chinese tertiary institutions. This retrospective study at our institution aimed to explore the effectiveness and challenges of the combined approach in diagnosing thyroid nodules and the correlation between BRAF V600E mutation status and behavior of papillary thyroid carcinoma.

METHODS

Thyroid FNA cytology and BRAF V600E mutation detection results were reviewed between November 2020 and July 2022. A total of 623 patients, each of whom underwent thyroidectomy and final pathological examination after FNA cytology diagnosis, were included in the study. The relationship between the BRAF V600E mutational status and pathological parameters was analyzed using the χ2 test. The effectiveness and challenges of FNA cytology alone and the combined procedure were also evaluated based on the final pathology.

RESULTS

Of 623 patients, 591 were diagnosed with papillary thyroid carcinoma (PTC), of which 456 were positive for the BRAF V600E mutation. It demonstrated near-perfect specificity for identifying PTC, and its incidence rate showed an age-specific curve with an inverted U-shaped distribution. The final pathological examination showed that the combined procedure had a higher sensitivity (83.91%) than FNA cytology alone (63.45%) for distinguishing PTC from other lesions (p < 0.001). Mutational status was associated with a larger maximum tumor diameter (p = 0.003) and a tendency of capsular invasion (p = 0.0542) but possibly unrelated to central lymph node metastasis (p = 0.1846). Nodular goiters accounted for most benign entities initially designated as Bethesda categories III-V.

CONCLUSION

BRAF V600E mutational analysis complements cytopathology and improves the PTC detection rate in FNA cytology samples due to the high prevalence of the mutation in China. BRAF V600E mutation does not show a statistical correlation with tumor aggressiveness. Morphological pitfalls such as histocyte aggregation, cystic-lining cells in nodular goiters, and oncocytes in Hashimoto's thyroiditis, were overwhelmingly found in BRAF V600E-negative specimens.

Effective Use of microRNA, BRAF and Sonographic Risk Assessment in Bethesda III Thyroid Nodules Requires a Different Approach to Nodules with Features of Nuclear Atypia and Other Types of Atypia

The aim of the study was to analyze the diagnostic usefulness of the combined assessment of the ultrasound risk category of the nodule (evaluated with EU-TIRADS system), the presence of BRAF V600E mutation and the expression of selected microRNAs (miR-146b, miR-221 and miR-222) in Bethesda category III thyroid nodules, separately for cases with nuclear atypia (AUS-nuclear) and cases with other types of atypia (AUS-other). We evaluated 161 nodules (66 AUS-nuclear and 95 AUS-other) with known results of postoperative histopathological examination. The rate of cancer and the rate of PTC among cancers were nearly three times higher in the AUS-nuclear than the AUS-other group. For AUS-nuclear nodules, the most effective diagnostic panel included, in addition to repeat FNA, the assessment of BRAF V600E mutation and the expression of miR-146b and miR-222 (sensitivity: 93.5%, specificity: 80.0%). For AUS-other nodules, a two-step procedure was most effective: at the first stage, forgoing surgical treatment in subjects with a benign repeat FNA outcome, and, at the second stage, the assessment of miR-222 expression and the EU-TIRADS category (sensitivity: 92.3%, specificity: 76.8%). The optimal use of molecular methods in the diagnostics of category III thyroid nodules requires a separate approach for nodules with nuclear atypia and nodules with other types of atypia.

Ultrasound Parameters Can Accurately Predict the Risk of Malignancy in Patients with "Indeterminate TIR3b" Cytology Nodules: A Prospective Study

The increase in the incidence of thyroid nodules with cytological findings of TIR3b requires the identification of predictive factors of malignancy. We prospectively evaluated 2160 patients from January 2018 to June 2022 and enrolled 103 patients with indeterminate cytology TIR3b nodules who underwent total (73 patients) and hemi-thyroidectomy (30 patients). Among them, 61 had a histological diagnosis of malignancy (30 classic papillary thyroid carcinoma, 19 had follicular papillary thyroid carcinoma variant, 3 had Hurtle cell carcinoma and 9 had follicular thyroid carcinoma), while 42 had a benign histology. Clinical, ultrasonographic and cytological characteristics were recorded. In addition, BRAF mutation was analysed. Patients with a histological diagnosis of malignancy had a higher frequency of nodule diameter ≤11 mm (p = 0.002), hypoechogenicity (p < 0.001), irregular borders (p < 0.001), peri- and intralesional vascular flows (p = 0.004) and microcalcifications (p = 0.001) compared to patients with benign histology. In contrast, patients with benign histology had more frequent nodules with a halo sign (p = 0.012) compared to patients with histological diagnosis of malignancy. No significant differences were found in BRAF mutation between the two groups. Our study suggests that the combination of ultrasonographic and cytological data could be more accurate and reliable than cytology alone in identifying those patients with TIR3b cytology and a histology of malignancy to be referred for thyroidectomy, thus reducing the number of patients undergoing thyroidectomy for benign thyroid disease.

Fine-needle Aspiration Washout Precipitation Specimens: An Acceptable Supplement to Genetic Mutation Detection of Thyroid Nodules

Objectives: Thyroid nodules are common in adults, but only some of them are malignant. Ultrasound-guided fine-needle aspiration (FNA) is widely applied as a reliable and minimally invasive technique for evaluating thyroid nodules. However, the scarcity of FNA biopsy specimens poses a challenge to molecular diagnosis. This study aimed to evaluate the feasibility of FNA washout precipitation specimens as an effective supplement to the thyroid genetic test. Methods: A total of 115 patients with thyroid nodules were enrolled in our study. The BRAF V600E mutation status was detected in all FNA washout precipitation specimens and biopsy formalin-fixed paraffin-embedded (FFPE) specimens using an amplification refractory mutation system PCR (ARMS-PCR). All patients underwent cytological diagnoses; 79 patients also underwent surgery for histopathological analysis. Results: All the 115 samples were successfully analyzed using both FNA washout precipitation and biopsy FFPE specimens. The results showed that the BRAF V600E status detected in 96 FNA washout precipitation specimens were consistent with that in FNA biopsy FFPE specimens, including 41 BRAF V600E positive and 55 BRAF V600E negative, achieving a concordance rate of 84.4% (kappa  =  0.689). Furthermore, the BRAF V600E mutation status using FNA washout precipitation specimens provided a 100.0% positive predictive value for diagnosing papillary thyroid carcinoma in patients with The Bethesda system for reporting thyroid cytopathology (TBSRTC) V. Besides, the BRAF V600E mutation status was positive in 90.9% (10/11) FNA washout precipitation specimens from patients with capsule invasion, achieving a higher overall sensitivity of 100.0%, compared with 57.1% of FNA washout precipitation specimens from patients without capsule invasion. Conclusion: These results suggested that FNA washout precipitation specimens might be a valuable supplementary sample type for detecting the BRAF V600E mutation in patients with thyroid nodules, especially with thyroid capsule invasion.