Application of Endobronchial Ultrasonography for the Preoperative Detecting Recurrent Laryngeal Nerve Lymph Node Metastasis of Esophageal Cancer

BACKGROUND: The preoperative detection of recurrent laryngeal nerve lymph node (RLN LN) metastasis provides important information for the treatment of esophageal cancer. We investigated the possibility of applying endobronchial ultrasonography (EBUS) with conventional preoperative endoscopic ultrasonography (EUS) and computerized tomography (CT) examination to evaluate RLN LN metastasis in patients with esophageal cancer. METHODS: A total of 115 patients with advanced thoracic esophageal cancer underwent EBUS examinations. Patients also underwent EUS and CT imaging as reference diagnostic methods. Positron emission tomography /computed tomography (PET/CT) was also introduced in partial patients as reference method. The preoperative evaluation of RLN LN metastasis was compared with the surgical and pathological staging in 94 patients who underwent radical surgery. RESULTS: The sensitivities of the preoperative evaluations of RLN LN metastasis by EBUS, EUS and CT were 67.6%, 32.4% and 29.4%, respectively. The sensitivity of EBUS was significantly different from that of EUS or CT, especially in the detection of right RLN LNs. In addition, according to the extra data from reference method, PET/CT was not superior to EBUS or EUS in detecting RLN LN metastasis. Among all 115 patients, 21 patients who were diagnosed with tracheal invasions by EUS or EBUS avoided radical surgery. Another 94 patients who were diagnosed as negative for tracheobronchial tree invasion by EUS and EBUS had no positive findings in radical surgery. CONCLUSIONS: EBUS can enhance the preoperative sensitivity of the detection of RLN LN metastasis in cases of thoracic esophageal cancer and is a useful complementary examination to conventional preoperative EUS and CT, which can alert thoracic surgeons to the possibility of a greater range of preoperative lymph node dissection. EBUS may also indicate tracheal invasion in cases of esophageal stricture.