Clinicopathologic correlations of the BRAFV600E mutation, BRAF V600E immunohistochemistry, and BRAF RNA in situ hybridization in papillary thyroid carcinoma

The BRAFV600E mutation is the most common genetic alteration in papillary thyroid carcinoma (PTC). The aim of this study is to analyze the clinicopathologic correlations of the BRAFV600E mutation, BRAF V600E immunohistochemistry (IHC) and BRAF RNA in situ hybridization (ISH) in PTC. This study included 467 patients with PTC who underwent surgical resection. We studied the BRAFV600E mutation using real-time PCR and BRAF V600E and BRAF RNA ISH using tissue microarray (TMA). The frequencies of a positive BRAFV600E mutation by real-time PCR, positive BRAF V600E IHC, and high BRAF RNA ISH were 84%, 86%, and 70%, respectively, in PTC. Conventional PTC had higher positive rates in all three tests than other histologic types. The BRAFV600E mutation, BRAF V600E IHC, low ΔCt, and high BRAF RNA ISH were significantly associated with lymph node metastasis. The BRAFV600E mutation was significantly associated with positive immunostaining for BRAF V600E mutant protein (P