The role of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) following integrated PET/CT scanning in mediastinal staging of non-small cell lung cancer (NSCLC) has not been assessed.
We prospectively evaluated the diagnostic values of PET/CT scanning and EBUS-TBNA for mediastinal staging in 117 patients with potentially operable NSCLC with accessible mediastinal lymph nodes (diameter range, 5 to 20 mm) by EBUS-TBNA. Subgroup analysis according to histologic type was performed.
Of 30 cases of mediastinal metastasis, 27 were confirmed by EBUS-TBNA and 3 were confirmed by surgery. EBUS-TBNA results confirmed all cases with true-positive PET/CT scan findings and six of nine cases with false-negative PET/CT scan findings. The sensitivity, specificity, positive predictive value, negative predictive value (NPV), and accuracy of EBUS-TBNA in the detection of mediastinal metastasis were 90.0%, 100%, 100%, 96.7%, and 97.4%, respectively. For PET/CT scans, the values were 70.0%, 59.8%, 37.5%, 85.2%, and 62.4%, respectively (p = 0.052; p < 0.001; p < 0.001; p = 0.011; p < 0.001, respectively). In adenocarcinoma (n = 55), EBUS-TBNA detected four of six cases with false-negative PET/CT scan findings, and the NPV was higher for EBUS-TBNA than for PET/CT scans (94.6% vs 77.8%, respectively; p = 0.044). In squamous cell carcinoma (n = 53), the NPV of EBUS-TBNA and PET/CT scans were similarly high (97.9% vs 96.3%, respectively; p = 0.689).
EBUS-TBNA was an effective invasive method following PET/CT scanning in the mediastinal staging of potentially operable NSCLC. In mediastinal PET/CT scan-positive cases, EBUS-TBNA was an excellent tool for detecting mediastinal metastasis. Even in mediastinal PET/CT scan-negative cases, EBUS-TBNA can be useful for confirming mediastinal metastases, especially in adenocarcinoma.