Efficacy of Endobronchial Ultrasound-Guided Transbronchial Needle Biopsy for the Diagnosis of Intrathoracic Lymph Node Metastases from Extrathoracic Malignancies

Objective: Intrathoracic lymph node enlargement is common among patients with extrathoracic malignancies. While endobronchial ultrasound-guided-transbronchial needle aspiration (EBUS-TBNA) is often used for diagnosing mediastinal or hilar lymph nodes and for staging lung cancer, there are still a few studies demonstrating the use of EBUS-TBNA for determining intrathoracic metastases from extrathoracic malignancies. The aim of this study is to evaluate the role of EBUS-TBNA for the diagnosis of extrathoracic malignancies.
Methods: From March 2010 to July 2015, 190 patients with known extrathoracic malignancy, who underwent diagnostic convex probe (CP)-EBUS-TBNA due to suspicion of metastases, were included in the study. The patients’ data were retrospectively investigated.
Results: The findings of EBUS-TBNA were examined; 61 patients (32%) were malignant, 121 (63%) were benign, and 3 (1.5%) were not diagnostic. Five patients (3.5%) were not sampled because of the millimetric size of the lymph nodes. There was no progression at the 12-month follow-up in these patients. Among the malignancy patients, 40 had extrathoracic malignancy-related intrathoracic metastases. The diagnosis of the lymph nodes with EBUS-TBNA and the final diagnosis at follow-up are given as summarized. The size of the lymph node decreased during clinical follow-up in one of the three non-diagnostic patients (accepted as having reactive lymph node). The other two patients were diagnosed as malignant using mediastinoscopy (having esophageal cancer and squamous cell lung cancer). The sensitivity was found to be 95.3%, specificity was 100%, the negative predictive value was 97.6%, and the diagnostic accuracy rate was 98.4%.
Conclusion: EBUS-TBNA is a simple, reliable, and adequate diagnostic method for determining intrathoracic lymph node metastases related to known extrathoracic malignancies.