Mediastinal restaging: EUS-FNA offers a new perspective.

STUDY OBJECTIVE We hypothesized that transoesophageal endoscopic ultrasound guided fine needle aspiration (EUS-FNA) has the potential to be a valuable and accurate new diagnostic technique for mediastinal restaging in non-small cell lung cancer (NSCLC) after induction chemotherapy. The current restaging modalities either have a low diagnostic accuracy (computed tomography (CT) scan of the thorax) or they are invasive, can be technically difficult and are therefore not commonly performed (remediastinoscopy). METHODS AND PATIENTS Nineteen consecutive patients with NSCLC and proven ipsilateral or subcarinal lymph node metastases (N2 disease) who had been treated with induction chemotherapy underwent mediastinal restaging by EUS-FNA. Patients had either a partial response (n=14) or stable disease (n=5) based on sequential CT scans of the thorax. INTERVENTIONS EUS-FNA was performed in an ambulatory setting with biopsy of mediastinal lymph nodes (LN). No complications occurred. When EUS-FNA restaged the mediastinum as no regional lymph node metastasis (N0), surgical resection of the tumour with lymph node sampling or dissection was performed. RESULTS The positive predictive value, negative predictive value, sensitivity, specificity and diagnostic accuracy of EUS-FNA in restaging mediastinal LN were 100, 67, 75, 100 and 83%, respectively. CONCLUSIONS AND SIGNIFICANCE EUS-FNA qualifies as an accurate, safe and minimally invasive diagnostic technique for the restaging of mediastinal lymph nodes after induction therapy in NSCLC. In the future EUS-FNA might play an important role in the mediastinal restaging in NSCLC, particularly to identify the subgroup of down staged patients who benefit most from further surgical treatment.