ObjectiveTo study the expressions of BRAF gene in papillary thyroid microcarcinoma (PTMC) and papillary thyroid carcinoma (PTC) >1 cm in diameter, and the invasiveness of PTMC and PTC. MethodsThe data of 275 patients with PTC received surgical treatment and with BRAF gene mutation results in West China Hospital of Sichuan University from 2011 September to 2013 September were retrospectively analyzed. According to the size of tumors, the patients were divided into three groups, was the diameter <1 cm group, 1 cm< diameter≤2 cm group, and diameter >2 cm group,respectively. The ratio of BRAF gene mutation, and the degree of risk of extrathyroidal invasion and lymph node metastasis were compared. ResultsUnivariate analysis showed that tumor size was not related with the age, gender, and BRAF gene mutation rate (P>0.05), while the tumor size was related with the extrathyroidal invasion and lymph node metastasis (P<0.05), and the ratio of BRAF gene mutation was related with the extrathyroidal invasion and lymph node metastasis (P<0.05). Multivariate analysis showed that tumor size was associated with extrathyroidal extension (P=0.009) and lymph node metastasis (P=0.000). ConclusionsBRAF gene mutation can increase the extrathyroidal invasion and lymph node metastasis risk of PTC, and it is no significantly correlated with tumor size of PTC. The invasiveness of PTC increases with the increased of tumor size, but the PTMC of BRAF gene mutation positive is still require positive treatment.
ObjectiveTo investigate research advance on the value of B-type RAF kinase (BRAF) gene mutation assisted diagnosis of papillary thyroid cancer (PTC) in thyroid nodule.MethodThe recent literatures on the BRAF gene mutation and its combination with fine needle aspiration cytology (FNAC) in the diagnosis of benign and malignant thyroid nodules and PTC were collected and reviewed.ResultsThe BRAFV600E gene mutation was the most common type of gene mutation in the genetic molecule of PTC. The combination of the FNAC and BRAF gene mutation detection could improve the diagnostic value of the benign and malignant thyroid nodules, especially the diagnostic accuracy of PTC. However, the negative detection of BRAF gene mutation did not rule out the possibility of PTC. It still remained controversial that the detection of BRAF gene mutation could differentiate between the benign and malignant thyroid nodules.ConclusionsBRAF gene mutation detection has different diagnostic values in different types of thyroid nodules. It has considerable diagnostic value in thyroid nodules with high BRAF mutation incidence (suspicious for malignancy, undetermined significance or follicular lesion of undetermined significance nodules) while presents false negative result in thyroid nodule with very low mutation incidence category to a large extent. BRAF gene detection might become a specific diagnostic molecular marker to promote diagnosis accuracy of PTC.