Clinical Significance of BRAF Mutation in Papillary Cancer.

Objective: BRAF mutation represents the most common oncogenic event in sporadic papillary thyroid cancer (PTC). There are, however, significant discrepancies regarding the overall frequency and its relationship with clinico‐pathological parameters of poor outcome. We analyzed BRAF mutation in a cohort of patients affected by PTCs, to identify its association with clinical variables. Method: We analyzed retrospectively a series of 304 patients, treated for PTC from 1992 to 2011 at Bologna University Hospital. We searched BRAF mutation by RT‐PCR followed by single‐stranded conformational polymorphism or by PCR and direct sequencing, to correlate the presence of the mutation with clinico‐pathological parameters of the patients. Results: BRAF mutation was found in 77.4% of classical PTCs, 31.9% of follicular variant, and 72.2% of high tall cell PTC, being significantly associated with recurrence (P. 005), stage (P. 043), and multicentricity (P. 025). Moreover BRAF was significantly associated with the classic variant of PTC (P. 0001). Higher T, but not N nor M stage, resulted to be associated to BRAF mutation. A significant difference of disease free survival time was found between BRAF mutation positive and BRAF mutation negative patients (P. 005) after a mean follow‐up of 60.2 months (range 10‐228). Conclusion: Our results indicate that BRAF mutation identifies a subset of PTC with increased risk of recurrence. The presence of BRAF mutation might be a valuable diagnostic and prognostic marker of the disease. In order to confirm the diagnostic usefulness of this marker, further studies should be carried out. [ABSTRACT FROM AUTHOR]