BRAF mutation may predict higher necessity of postoperative radioactive iodine ablation in papillary thyroid cancer

PURPOSE The primary aim of the present study was to analyze the association between high-risk clinicopathologic characteristics and the BRAFV600E mutation. METHODS From March 2010 to September 2012, we performed analysis of the BRAF mutation (assessing V600E point mutation of BRAF gene, exon 15, on chromosome 7q34 by real-time polymerase chain reaction kit) from 499 papillary thyroid carcinoma (PTC) patients who underwent thyroidectomy. We analyzed the relation between the mutation and known clinicopathologic risk factors of PTC. RESULTS BRAF mutations were found in 353 of 499 patients (70.7%). On univariate analysis, BRAF mutations were more frequently detected in patients with central lymph node metastasis (78.5% vs. 66.7%, P = 0.007) and classic PTC type (71.3% vs. 16.7%, P = 0.011). Patients with one or more aggressive pathologic feature such as lymph node metastasis, multifocality, and extrathyroidal extension showed higher BRAF mutation rate (73.5% vs. 62.3%, P = 0.022). BRAF mutation group showed more aggressive pathologic features, which is considered as higher necessity of radioactive iodine ablation (relative risk, 1.617; P = 0.035). CONCLUSION This study found that BRAF mutation is associated with classic PTC and central lymph node metastasis and higher necessity of radioactive iodine ablation.