Comparison between endobronchial ultrasound-guided transbronchial needle aspiration and 18F-fluorodeoxyglucose positron emission tomography in the diagnosis of postoperative nodal recurrence in patients with lung cancer

Abstract

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has a high diagnostic value for preoperative mediastinal staging in patients with lung cancer. In this study, the utility of EBUS-TBNA for the pathological diagnosis of postoperative lymph node recurrence was investigated and compared with that of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET). Patients who received both EBUS-TBNA and FDG-PET for the diagnosis of postoperative lymph node recurrence were retrospectively investigated. They underwent routine chest computed tomography (CT) follow-up after thoracotomy, and when hilar or mediastinal lymph nodes showed enlargement on CT compared with the previous chest CT, they were referred for FDG-PET and EBUS-TBNA. We compared the diagnostic performance of these two modalities. In addition, pathological findings of the biopsied sample were evaluated precisely and compared with the results of FDG-PET. Positivity for hypermetabolism on FDG-PET was defined as a standardized uptake value (SUV) greater than 2.5. A total of 40 patients were retrospectively reviewed. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of EBUS-TBNA were 100% for each parameter, whereas those of FDG-PET were 95.8, 12.5, 62.2, 66.7 and 62.5%, respectively. The SUV of true-positive nodes was significantly higher than that of false-positive nodes (P = 0.001). Twenty-two of 24 patients who were confirmed for recurrence by EBUS-TBNA underwent anticancer treatment. The pathological diagnoses of 14 false-positive cases by FDG-PET were chronic inflammation in 12 and non-specific granuloma in 2. The diagnostic yield of EBUS-TBNA is higher than that of FDG-PET when postoperative lymph node recurrence is suspected.