The True False Negative Rates of Esophageal and Endobronchial Ultrasound in the Staging of Mediastinal Lymph Nodes in Patients With Non-Small Cell Lung Cancer

Background. Accurate false negative rates for endobronchial ultrasound (EBUS) and esophageal ultrasound (EUS) for mediastinal (N2) lymph nodes are unknown. Methods. A retrospective review of patients with non-small cell lung cancer (NSCLC) underwent integrated positron emission tomography and computed tomography (PET/CT) and CT scan. All suspicious N2 lymph nodes were biopsied before thoracotomy. The EBUS was performed for suspicious nodes in stations 2R, 4R, 4L, 5, and 7; the EUS was performed for 4L, 4R, 5, 7, 8, and 9. Mediastinoscopy was performed in selected patients if they were negative by EUS/EBUS; if N2 negative, all patients underwent thoracotomy with complete thoracic lymphadenectomy. Results. There were 425 patients over a 2-year period, and 234 had suspected N2 disease. Of these patients, 72 had an EBUS; 16 were positive for N2 disease and 12 were false negative (7 patients at station 4R/4L, 4 patients at station 7; patient sensitivity 57%, negative predictive value 79%, accuracy 83%). Seventy-nine patients had EUS; 20 patients were positive for N2 disease and 12 were false negative (4 patients at station 4R/4L, 4 patients at station 7; patient sensitivity 63%, negative predictive value 80%, accuracy 85%). One hundred and forty-six patients had mediastinoscopy, which revealed N2 or N3 disease in 42 patients, and 7 were false negative (patient sensitivity 88%, negative predictive value 93%, accuracy 95%). Conclusions. Both EBUS and EUS are useful initial tests to biopsy suspicious N2 mediastinal lymph nodes; however, as EBUS and EUS have high false negative rates, especially at stations 4R and 7, mediastinoscopy is still required for patients with suspicious nodal disease in these stations. (Ann Thorac Surg 2010;90:427-34) (C) 2010 by The Society of Thoracic Surgeons