Immunohistochemistry is highly sensitive and specific for detecting the BRAF V600E mutation in papillary thyroid carcinoma

The V600E mutation in the B-type Raf kinase (BRAF) gene is a common genetic change in cases of papillary thyroid carcinoma (PTC) that appears to play a key role in the development and progression of this disease. We sought to assess the sensitivity and specificity of immunohistochemical detection of this mutation with a V600E mutated BRAF antibody in a Chinese PTC cohort. In this study, we used fully automated immunohistochemistry (IHC) assay with a BRAF V600E (VE1) mouse monoclonal primary antibody to screen for the BRAF V600E mutation in 556 cases of PTC. Moreover, to verify the IHC staining results, real-time PCR was applied to detect this mutation in the same patient cohort. Among the 556 cases in the examined primary PTC cohort, 414 (74.5%) cases and 419 (75.4%) cases were positive for the BRAF V600E mutation by IHC staining and by real-time PCR, respectively. The real-time PCR results indicated that the sensitivity and specificity of IHC staining for the BRAF V600E mutation were 98.8% and 100%, respectively. The BRAF V600E mutation was common among Chinese patients with primary PTC, and was strongly correlated with older patient age and the conventional subtype of PTC but was not associated with parameters of clinicopathological aggressiveness. The fully automated IHC is a reliable technique that can serve as an alternative to molecular biological approaches for the routine detection of the BRAF V600E mutation in PTC patients.