Detection of BRAF V600E mutation with thyroid tissue using pyrosequencing: comparison with PNA-clamping and real-time PCR.

Abstract

We used pyrosequencing, peptide nucleic acid (PNA)–clamping polymerase chain reaction (PCR), and real-time PCR to detect the BRAF V600E mutation and to investigate the prognostic effect of the BRAF V600E mutation in paraffin block specimens from 100 patients diagnosed with papillary thyroid carcinoma. Positive rates of PNA-clamping PCR, real-time PCR, and pyrosequencing were 66%, 70%, and 68%, respectively. Pyrosequencing and PNA-clamping PCR detected mutant type in a 99:1 (wild-type: mutant) DNA concentration, and PNA-clamping PCR detected mutant type in a 99.5:0.5 DNA concentration. Clamping PCR showed higher κ value than real-time PCR (0.729 vs 0.626). The BRAF V600E mutation was associated with an advanced stage of cancer (P = .045) and was found to be associated with poor prognostic factors. This study suggests that pyrosequencing can be as sensitive as real-time PCR and that PNA-clamping PCR is a sensitive and reliable method to detect the BRAF V600E mutation