BRAF^V600E mutation in Turkish patients with papillary thyroid cancer: strong correlation with indicators of tumor aggressiveness

Papillary thyroid cancer (PTC) constitutes more than 90 % of the thyroid cancers. MAP kinase/ERK pathway plays an important role in the development of several cancers. BRAF which is a member of Raf-kinase family activates this way. BRAF gene activating mutations lead to neoplastic transformation in thyroid follicle cells. In PTC, this mutation itself is a poor prognostic sign independent of other clinicopathological characteristics. We evaluated BRAF^V600E mutation and clinical–pathological characteristics in Turkish population with PTC. We assessed 109 patients with PTC (88 female, 21 male). The average age was 38.7 ± 9.9 (17–71). BRAF^V600E mutation was detected using polymerase chain reaction and fluorescent melting curve analysis. The results show that BRAF^V600E mutation rate was found in 39.45 % of our patients. We observed that BRAF^V600E mutation was significantly higher in men, in tumors larger than 1 cm in size, and in patients with classical PTC. Moreover, statistically significant correlations of BRAF^V600E with indicators of tumor aggressiveness such as thyroid capsular invasion, multifocality, lymph node metastasis, and extrathyroidal spread were found. Patient groups below and over the age of 45 did not differ in mutation frequency. Patients with micro-PTC were evaluated separately, it was found that BRAF^V600E mutation was more frequent in the classic type and that lymph node metastasis rate significantly increased when the mutation was present. We concluded that BRAF^V600E was correlated with indicators of tumor aggressiveness in our study population. This fact is taken into consideration in treatment and follow-up of our patients with PTC and positive BRAF^V600E mutation.