Transesophageal endoscopic ultrasound-guided fine-needle aspiration for the mediastinal staging of extrathoracic tumors: a new perspective.

BACKGROUND Several extrathoracic tumors metastasize to the mediastinum. Mediastinoscopy is the standard method to obtain tissue proof of mediastinal spread, but drawbacks are its invasiveness, requirement for general anesthesia and costs. Transesophageal endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is indicated in lung cancer staging guidelines as a minimally invasive alternative for surgical staging. The diagnostic values in patients with suspected mediastinal metastases and various (previous) extrathoracic malignancies were assessed. PATIENTS AND METHODS Consecutive patients with suspected mediastinal metastases (on computed tomography or positron emission tomography) and an (previous) extrathoracic malignancy underwent EUS-FNA. RESULTS Seventy-five patients with current (n = 14) or previously diagnosed (n = 61) extrathoracic malignancies were evaluated. EUS-FNA detected mediastinal malignancies in 43 patients (57%) [metastases of extrathoracic tumors, n = 36 (48%); second malignancy (lung cancer), n = 7 (9%)]. Mediastinal metastases were found at subsequent surgical staging in seven patients or during follow-up (one patient). In seven patients, an alternative diagnosis was established. Sensitivity, specificity, accuracy and negative predictive value of EUS-FNA for mediastinal staging were 86%, 100%, 91% and 72%, respectively. CONCLUSION EUS-FNA is a minimally invasive mediastinal staging method for patients with extrathoracic malignancies to confirm nodal metastatic spread and therefore may qualify as an alternative for surgical staging.