Outcomes of mediastinoscopy and surgery with or without neoadjuvant therapy in patients with non-small cell lung cancer who are N2 negative on positron emission tomography and computed tomography.

Introduction: The objectives of this study were (1) to assess the results of mediastinoscopy and mediastinal lymphadenectomy and (2) to compare outcomes of surgical treatment with or without neoadjuvant therapy in patients with non-small cell lung cancer who are N2 negative on integrated positron emission tomography and computed tomography (PET/CT).
Methods: This was a retrospective, single-institution review of patients with non-small cell lung cancer who were N2 negative on CT and PET/CT. All patients underwent mediastinoscopy; if N2 positive, patients underwent neoadjuvant therapy followed by pulmonary resection, and if N2 negative, patients underwent pulmonary resection with mediastinal lymphadenectomy.
Results: Between 2003 and 2007, there were 750 patients (547 men). Of these, 51 patients were N2 positive at mediastinoscopy and then underwent neoadjuvant therapy (mediastinoscopy N2 group), and 699 were N2 negative at mediastinoscopy and then underwent mediastinal lymphadenectomy. Mediastinal lymphadenectomy revealed that 635 had N0 or N1 disease (N2-negative group), and 64 had N2 disease (surgery N2 group). Overall 5-year survival was 73% for the N2-negative group, 44% for the surgery N2 group, and 47% for the mediastinoscopy N2 group. Disease-free 5-year survival was 59% for the N2-negative group, 27% for the surgery N2 group, and 29% for the mediastinoscopy N2 group.
Conclusions: We found that there were no significant differences in overall and disease-free survivals between the surgery N2 group and the mediastinoscopy N2 group. The benefit of neoadjuvant therapy in patients with PET/CT-negative but mediastinoscopy-positive N2 disease should be confirmed by randomized studies.