The BRAF mutation analysis and risk stratification in papillary thyroid carcinoma.

OBJECTIVE

Although the prognostic role of BRAF mutation in papillary thyroid carcinoma (PTC) is controversial, the American Thyroid Association (ATA) includes the mutational status in their risk stratification system. To evaluate the impact of the BRAF mutation status on PTC risk stratification.

METHODS

PTC patients attending a university-based hospital who had the analysis of the BRAF mutation were included. Persistent disease was defined as the presence of biochemical or structural disease. The performance of the ATA risk stratification system on predicting persistent disease with or without the BRAF mutation status information was evaluated.

RESULTS

Of the 134 patients evaluated, 44 (32.8%) carried BRAF mutation. The median tumor size was 1.7 cm (P25-75 1.0-3.0), 64 (47.8%) patients had lymph node, and 11 (8.2%) distant metastases. According to the ATA risk stratification system, patients were classified as low, intermediate, and high risk in 55 (41%), 59 (44%), and 20 (14%) patients, respectively. The data on BRAF mutation reclassified 12 (8.9%) patients from low to intermediate risk. After a median follow-up of 8.5 years, the prevalence of persistent disease was similar in patients with and without BRAF mutation (P = 0.42). Multivariate analysis failed to demonstrate an association between the BRAF mutation and persistent disease status (RR 0.96; 95%CI 0.47-1.94). Notably, none of the patients reclassified from low to intermediate risk showed persistent disease on follow-up.

CONCLUSION

Inclusion of BRAF mutational status has a limited impact on risk stratification and does not add to the prediction of outcomes in PTC patients.