Detection of BRAF c.1799T > A (p.V600E) mutation using residual routine fine-needle aspiration specimens of papillary thyroid carcinoma

Abstract

Background BRAF p.V600E mutation is the most common genetic alteration in papillary thyroid cancer (PTC) and has been used as a diagnostic and prognostic marker in PTC. The aim of this study was to investigate the utility of preoperative BRAF p.V600E mutation analysis as an adjunctive diagnostic and prognostic tool to routine fine-needle aspiration (FNA). Methods Specimens were collected from thyroid nodules by FNA. Cytology diagnosis and BRAF p.V600E testing were performed on these specimens. Molecular and cytological results were correlated with histology outcomes. Results A total of 195 patients with thyroid nodules were enrolled, including 25 benign lesions and 170 PTCs. BRAF p.V600E testing was successfully performed in all specimens. The combination of BRAF p.V600E testing and cytology improved the sensitivity of cytology from 70% to 85.3% (P = 0.001). This significant increase in sensitivity was due to the detection of PTC by BRAF p.V600E testing in the nodules with atypical or suspicious PTC cytology results. Patients with BRAF p.V600E-positive tumors were significantly older than those who did not harbor mutations (45.6 years vs. 39.8 years, P = 0.002). No correlations between BRAF p.V600E mutation and other clinical-pathology parameters were observed. Conclusions Detection of BRAF p.V600E mutation can be successfully carried out using residual liquid-based materials. It can be performed as a diagnostic tool to supplement traditional thyroid FNA, especially in cases with atypical or suspicious PTC. However, the role of BRAF p.V600E in guidance of the extent of thyroidectomy and nodal clearance requires further study. Diagn. Cytopathol. 2015;43:786-790.