Correlation among the BRAF Gene Mutation Status, Clinicopathological Features of Primary Tumour, and Lymph Node Metastasizing of Papillary Thyroid Carcinoma
Abstract
Background: Papillary thyroid carcinoma (PTC) is the most common malignant thyroid tumour. A common mutation of papillary thyroid carcinoma (PTC) is the somatic mutation of the BRAF(V600E) gene.
Aim: The aim was to 1) determine the association of lymph node metastases of PTC with the BRAF gene mutation of primary tumour; 2) evaluate association of the BRAF mutation in the primary tumour with clinicopathological parameters; 3) examine the extent of genetic heterogeneity by monitoring the BRAF mutation in multicentric tumours. Subjects and methods: Retrospective analysis of the BRAF(V600E) mutation in PTC and PTC neck lymph node metastases in 156 patients operated from 2003 to 2012 in Prague and Zlin, the Czech Republic, using a qPCR assay.
The results were correlated with clinicopathological factors. Results: DNA was successfully extracted from 137 samples.
The BRAF(V600E) mutation was detected in 78 cases (56.9 %). The patients with BRAF p.Val600Glu mutation of primary tumour had only non-significantly higher risk of cervical lymph node metastases [OR = 2.39 (95 %) CI 1.00-5.75, p = 0.052].
In the classic papillary variant, the BRAF(V600E) mutation was found significantly more often than in other PTC subtypes (p = 0.022). We did not confirm any significant association between the BRAF(V600E) mutation and other clinicopathological findings.
Conclusion: Except for the higher prevalence in papillary variant of PTC, BRAF p.Val600Glu mutation was not associated with other prognostic clinicopathological factors of PTC. BRAF mutation cannot be regarded as a reliable marker of node metastases in patients with PTC.