Analysis Of BRAF Gene Mutation In Thyroid And KAP-1Protein Expression In Papillary Thyroid Carcinoma

Objective:To investigate the significance of BRAFV600E mutation in thyroid FNAB samples and to analyze the clinical influence of BRAFV600E mutation and/or KAP-1protein expression in papillary thyroid carcer.Methods:Eighty cases of FNAB washing fluid were detected to identify the BRAFV600E mutation by polymerase chain reaction(PCR) and direct DNA sequencing. In addition,40PTC samples were harvested after operation and BRAFV600E mutation was detected by direct DNA sequencing and KAP-1expression was measured by immunohistochemical SV method. Clinical and pathological features were analyzed between the BRAFv600E mutation (n=13) and KAP-1protein expression (n=29).We also compared the clinical and pathological features between the concurrent BRAFv600E mutation and KAP-1protein expression group (n=10) and BRAFV600E mutation or KAP-1expression alone group (n=22)Results:①Among80FNAB washing fluid samples, the number of BRAFV600E mutation is15,40cytologogical benign samples showed no positive BRAFV600E mutation, Among17confirmed PTC cases,5have BRAFV600E mutation cases(29.41%) and the rate of BRAFV6OOE mutation is43.48%(10/23) in the rest samples. All postoperative pathological were confirmed as PTC with positive BRAFv600E mutation preoperation.②Among37surgical patients who underwent FNA before operation, the malignant diagnosis rate of FNA combined with BRAF test is higher.③Of the40PTC patients, BRAFV600E mutation and KAP-1protein expression were detected in13patients(32.5%)and29patients (72.5%) respectively.④The BRAFV600E mutation was positively correlated with capsule invasion, lymph node metastasis, tumor clinical stage and differentiated degree at a significant level (P<0.05).⑤KAP-1protein expression was correlated with tumor size (P=0.009) and differentiated degree (P=0.017) at a significant level.⑥Compared with the BRAFV600E mutation or KAP-1protein expression alone group, the concurrent BRAFV600E mutation and KAP-1protein expression group had relatively poorer tissue differentiation and higher prognostic score (P=0.026)Conclusions:①BRAFV600E mutation was detected in cells aspirated washing fluid from a thyroid nodule.②FNA combined with BRAF test is useful in confirming or establishing the preoperative diagnosis of PTC.③The BRAFV600E mutation is associated with Capsule invasion, lymph node metastasis, tumor clinical stage and differentiated degree.④KAP-1can express more in PTC patients with less size and poorer differentiation.⑤PTC patients with concurrent BRAFV600E mutation and KAP-1protein expression present poorer differentiation, more highly aggressive variant in carcinoma tissues.