Is the BRAF(V600E) mutation useful as a predictor of preoperative risk in papillary thyroid cancer?

Abstract

Objective: Recent studies have shown that a BRAF(V600E) reflects poor prognosis, mainly in Western countries. However, some clinicians in Japan have suggested that the BRAF(V600E) mutation is not associated with a poor prognosis. Therefore, we investigated a relationship between BRAF(V600E) mutation and clinicopathologic factors.

Methods: From September 2008 to December 2009, we performed routine analysis of the BRAF(V600E) mutation using thyroid cancer tissue from 424 patients who underwent thyroidectomy with cervical lymph node dissection.

Results: The BRAF(V600E) mutation was found in 335 of 424 cases (79%) and was higher in classic papillary thyroid carcinoma (PTC) (79.7%) than in the follicular variant of PTC (62.5%) (P = .019). On univariate analysis, the BRAF(V600E) mutation was associated with extrathyroidal extension (P = .009) and variants of PTC (P = .019), but a high-risk Metastasis, Patient Age, Completeness of resection, local Invasion and Tumor Size (MACIS) score (≥ 6) (P = .146) and lymph node metastasis (P = .628) were not significantly associated with the BRAF(V600E) mutation. Multivariate analysis showed that extrathyroidal extension is independently associated with the BRAF(V600E) mutation (relative ratio: 2.466; 95% confidence interval, 1.213-5.011; P < .013).

Conclusion: It is not clear that the BRAF(V600E) mutation is useful for prediction of poor prognosis of PTC.