Introduction: Selected patients with stage III (N2/N3) non-small cell lung cancer (NSCLC) who are downstaged to N0 by chemoradiation therapy might benefit from subsequent surgical resection of the tumor. How mediastinal lymph nodes can be best reevaluated is subject of debate. Transesophageal ultrasound-guided fine-needle aspiration (EUS-FNA) is a minimally invasive technique to sample mediastinal nodes. We assessed sensitivity and false-negative rate of EUS-FNA for the mediastinal restaging of patients with stage III NSCLC.
Methods: Fifty-eight consecutive patients with stage III NSCLC and tissue-proven lymph node metastases N2/N3) who underwent EUS-FNA for restaging purposes after chemoradiation therapy were retrospectively analyzed. Surgical-pathological staging was used as the reference standard for nodal metastases.
Results: EUS-FNA found persistent nodal metastases (N2/N3) in 15 patients (26%). Of the 43 patients without persistent mediastinal metastases at EUS, 33 patients subsequently underwent surgical verification of the mediastinal nodes in whom persistent metastases (yN2/N3) were found in 19 patients (58%), and loco-regional downstaging (yN0) was achieved in the other 14 (42%). The prevalence of persistent nodal metastases in the 48 patients who could be analyzed was 71%. Sensitivity and the false-negative rate of EUS-FNA for mediastinal restaging were 44 and 58%, respectively.
Discussion: For mediastinal restaging of stage III NSCLC, EUS-FNA is a minimally invasive and safe method to confirm persistent nodal metastases, but this technique has a low negative predictive value and is therefore not useful for the exclusion of mediastinal metastases. Surgical restaging is indicated in the absence of mediastinal metastases at EUS-FNA.