Associations of the BRAFV600E Mutation with Sonographic Features and Clinicopathologic Characteristics in a Large Population with Conventional Papillary Thyroid Carcinoma

Abstract

OBJECTIVE: To evaluate the association of the BRAFV600E mutation with sonographic features and clinicopathologic characteristics in a large population with conventional papillary thyroid carcinoma (PTC). METHODS: We retrospectively reviewed the sonographic features, clinicopathologic characteristics, and presence of the BRAFV600E mutation in 688 patients who underwent thyroidectomy for conventional PTC between January and July 2010 at a single institution. The incidence of the BRAFV600E mutation was calculated. The sonographic features and clinicopathologic characteristics were compared between BRAF-positive and BRAF-negative patients. BRAF-positive patients were subdivided into those with papillary thyroid microcarcinoma (the PTMC group) and those with PTC larger than 10 mm (the PTC>10 mm group), and their sonographic features were compared. RESULTS: The BRAFV600E mutation was detected in 69.2% of patients (476 of 688). Sonographic features were not significantly different between BRAF-positive and BRAF-negative PTC, nor between PTMC and PTC>10 mm groups. The BRAFV600E mutation was associated with male sex (P = 0.028), large tumor size, extrathyroidal extension, central and lateral lymph node metastasis, and advanced tumor stage (P<0.0001). CONCLUSION: The BRAFV600E mutation was significantly associated with several poor clinicopathologic characteristics, but was not associated with sonographic features, regardless of tumor size. We recommend that patients with a thyroid nodule with any suspicious sonographic feature undergo preoperative BRAFV600E testing for risk stratification and to guide the initial surgical approach in PTC.