Application of ultrasound-guided fine-needle aspiration combined with BRAF V600E mutation detection and ultrasound features in estimating central cervical lymph nodes metastasis of classic papillary thyroid cancer

Objective To explore the correlation of ultrasound-guided fine-needle aspiration(US-FNA) combined with BRAF V600E mutation detection and ultrasound features and central cervical lymph nodes metastasis of classic papillary thyroid cancer(PTC) for providing a reliable molecular basis for clinical preoperative evaluation of patients. Methods Ninty-three cases of patients collected from October 2017 to November 2018 in Gansu Province Hospital were enrolled, who underwent general ultrasonic examination TI-RADS ≥4a, the US-FNA highly suspicious of PTC, thyroid surgery including total thyroidectomy and central cervical lymph node dissection, with the postoperative pathologic results of classical PTC and whether the central cervical lymph node metastasis happened in the patients. Part of the specimen applied HE staining for cytological diagnosis, the other part of specimen was used real-time for detection of BRAF V600E gene mutation by fluorescent quantitative polymerase chain reaction (PCR) method. Results Univariate analysis showed that the occurrence of cervical lymph node metastasis for classic PTC were significantly correlated with gender(χ2=10.303, P=0.002), BRAF V600E mutation(χ2=31.204, P=0.000) and extrathyroidal invasion(χ2=12.848, P=0.000). Multi-logistic regression analysis showed that BRAF V600E mutation(OR=13.324, 95%CI=4.058-43.744, P=0.000) and extrathyroidal invasion(OR=5.738, 95%CI=1.766-18.643, P=0.004) were the risk predictors of cervical lymph node metastasis of classic PTC. Gender(OR=0.385, 95%CI=0.112-1.324, P=0.130) was not the risk predictor. Conclusions US-FNA combined with BRAF V600E mutation and extrathyroidal invasion are the risk factors in predicting central cervical lymph node metastasis in classic PTC. Patients with these two risk factors should be elected to undergo prophylactic central cervical lymph node dissection. Key words: Ultrasound-guided fine-needle aspiration cytology; Papillary thyroid cancer, classic; Central cervical lymph node; Metastasis; BRAF V600E