Objective: Precise restaging of non-small cell lung cancer after induction therapy is of utmost importance. Remediastinoscopy remains a controversial procedure. In a combined, updated series of two thoracic centres, accuracy and survival of remediastinoscopy were determined. Methods: From November 1994 to August 2005, remediastinoscopy was performed in 104 patients (98 men, 6 women) after induction therapy for locally advanced non-small cell lung cancer. Mean age was 64.3 years (range 38-85). Neoadjuvant chemotherapy was given in 79 patients and chemoradiotherapy in 25. Follow-up data were completed in January 2007. Results: Remediastinoscopy was technically feasible in all patients except for one who died due to perioperative haemorrhage. Remediastinoscopy was positive in 40 patients and negative in 64; the latter group underwent thoracotomy. There were 17 false-negative remediastinoscopies. Sensitivity of remediastinoscopy was 71%, specificity 100% and accuracy 84%. Follow-up was complete for all patients. Sixty-nine died, mostly of distant metastases. Median survival time for the whole group was 18 months (95% confidence interval 11-25). Median survival time in patients with a positive remediastinoscopy was 14 months (95% confidence interval 8-20), with a negative remediastinoscopy 28 months (95% confidence interval 15-41) and with a false-negative remediastinoscopy 24 months (95% confidence interval 3-45). In univariate analysis the difference between positive and negative remediastinoscopies was highly significant (p = 0.001). In a multivariate analysis including sex, age, histology, centre, and nodal status at remediastinoscopy, only nodal status was a significant independent prognostic factor (p = 0.008). Conclusions: Remediastinoscopy is a valuable restaging procedure after induction therapy. Persisting mediastinal nodal involvement proven at remediastinoscopy heralds a poor prognosis. (C) 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.