Abstract
Objectives:
Papillary thyroid carcinoma is the most common type of thyroid cancer and is associated with BRAF (MIM 164757) mutations. Here, we report our 3 years of experience of pyrosequencing of BRAF hotspot regions in papillary thyroid carcinoma.
Methods:
Genomic DNA was isolated according to the manufacturer’s protocol (QIAamp DNA FFPE Tissue Kit) from formalin-fixed paraffin-embedded tumor samples of 181 female and 81 male patients pre-diagnosed with papillary thyroid carcinoma. Pyrosequencing of BRAF mutation regions (codon 600 and codon 464-469) was performed as indicated in the protocol of the kit used (therascreen BRAF Pyro Kit, Qiagen).
Results:
BRAF mutations were defined in 33.3% of samples tested. V600E mutation was the most frequent mutation (31.98%). V600K mutation was present in only two of the samples (0.9%), whereas G466E mutation was defined only in one sample (0.45%). Percentages of the mutations between male and female patients were not significantly different.
Conclusion:
Presence of a BRAF mutation is commonly accepted as an additional prognostic feature of papillary thyroid carcinoma following tumor histology, primary tumor size, and invasion. Our results confirm the high frequency of BRAF mutations in papillary thyroid carcinoma. As a second point, we suggest that pyrosequencing is a practical method to study targeted mutations in the tumor samples.
Keywords: Papillary thyroid carcinoma, BRAF, pyrosequencing, V600E, V600K, G466E
