Objective To explore the diagnostic value of endobronchial ultrasound?guided transbronchial needle aspiration ( EBUS?TBNA) in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results of EBUS?TBNA. Methods A retrospective analysis of the clinical and imaging data of 389 patients who underwent EBUS?TBNA for sampling enlarged hilar and mediastinal lymph nodes from October 2009 to October 2015 in Shandong Tumor Hospital, to evaluate its significance in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results. Results Among the 389 collected cases, positive biopsy results were obtained in 362 cases, and false negative results in 27 cases. The sensitivity, specificity, positive predictive value and negative predictive value were 92. 9%, 100%, 100% and 25. 0%, respectively. There was a positive correlation between the size of lymph node and biopsy positive rate (P=0.021). The subcarinal lymph nodes had the highest positive rate ( 97. 7%) , followed by the paratracheal lymph nodes ( 91. 2%) , with a statistically significant difference (P=0.006). The positive rates obtained by cytology (88.7%) and pathology (92.5%,) showed no significant difference ( P=0. 065 ) . The positive rate of EBUS?TBNA was not correlated with pathological types (P=0.932). Needle types (21G, 22G) had no significant effect on diagnosis accuracy (P=0.142). Conclusions EBUS?TBNA is a practical technology for diagnosis of enlarged mediastinal lymph nodes, with unique characteristics such as minimally invasiveness, local anesthesia, good safety and repeatability. Along with the accumulation of surgical experience, improvement of operative skills, more close cooperation between surgeons, cytologists and pathologists, false negative results will be reduced and positive rate of EBUS?TBNA examination will be further improved.

Objective To explore the diagnostic value of endobronchial ultrasound?guided transbronchial needle aspiration ( EBUS?TBNA) in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results of EBUS?TBNA. Methods A retrospective analysis of the clinical and imaging data of 389 patients who underwent EBUS?TBNA for sampling enlarged hilar and mediastinal lymph nodes from October 2009 to October 2015 in Shandong Tumor Hospital, to evaluate its significance in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results. Results Among the 389 collected cases, positive biopsy results were obtained in 362 cases, and false negative results in 27 cases. The sensitivity, specificity, positive predictive value and negative predictive value were 92. 9%, 100%, 100% and 25. 0%, respectively. There was a positive correlation between the size of lymph node and biopsy positive rate (P=0.021). The subcarinal lymph nodes had the highest positive rate ( 97. 7%) , followed by the paratracheal lymph nodes ( 91. 2%) , with a statistically significant difference (P=0.006). The positive rates obtained by cytology (88.7%) and pathology (92.5%,) showed no significant difference ( P=0. 065 ) . The positive rate of EBUS?TBNA was not correlated with pathological types (P=0.932). Needle types (21G, 22G) had no significant effect on diagnosis accuracy (P=0.142). Conclusions EBUS?TBNA is a practical technology for diagnosis of enlarged mediastinal lymph nodes, with unique characteristics such as minimally invasiveness, local anesthesia, good safety and repeatability. Along with the accumulation of surgical experience, improvement of operative skills, more close cooperation between surgeons, cytologists and pathologists, false negative results will be reduced and positive rate of EBUS?TBNA examination will be further improved.