Endobronchial ultrasound-guided transbronchial needle aspiration of hilar and mediastinal lymph nodes detected on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography

Objective: Endobronchial ultrasound-guided transbronchial needle aspiration is of diagnostic value in hilar/mediastinal (N1/N2) lymph node staging. We assessed the utility of endobronchial ultrasound-guided transbronchial needle aspiration in lung cancer patients with N1/N2 lymph nodes detected on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography. Methods: Fifty lung cancer patients with N1/N2 disease on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography underwent endobronchial ultrasound-guided transbronchial needle aspiration for pathological lymph nodes between November 2012 and April 2015. The diagnostic performance of endobronchial ultrasound-guided transbronchial needle aspiration, lymph node site and size, number of needle passes and complications were evaluated retrospectively from patients' medical records. Malignancy was defined as a maximum standardized uptake value (SUV_max) >2.5. Results: The median longest diameter of the 61 lymph nodes (29 subcarinal, 21 right lower paratracheal, 6 left lower paratracheal, 4 right hilar and 1 upper paratracheal) was 23.4 mm (range: 10.4-45.7); the median number of needle passes was 2 (range: 1-5). There were no severe complications. A definitive diagnosis was made by endobronchial ultrasound-guided transbronchial needle aspiration in 39 patients (31 adenocarcinomas, 3 small-cell carcinomas, 2 squamous-cell carcinomas, 3 large-cell neuroendocrine carcinomas). In the remaining 11 patients, the diagnosis was indefinite: insufficient endobronchial ultrasound-guided transbronchial needle aspiration material was collected in two patients and non-specific lymphadenopathy was confirmed by endobronchial ultrasound-guided transbronchial needle aspiration or thoracotomy in the other nine patients. The mean lymph node SUVmax was 7.09 (range: 2.90-26.9) and was significantly higher in true-positive than in false-positive nodes (P < 0.05, t-test). Non-specific lymphadenopathy was diagnosed by expert visual interpretation of cF-fluorodeoxyglucose positron emission tomography/computed tomography images in five of the nine patients. Conclusion: Endobronchial ultrasound-guided transbronchial needle aspiration accurately diagnoses N1/N2 disease detected on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography.