Safety and Utility of Mediastinoscopy in Non-Small Cell Lung Cancer in a Complex Mediastinum

Background Adequate mediastinal staging is crucial in patients with locally advanced non-small cell lung cancer. Mediastinoscopy is often omitted after induction therapy or prior mediastinoscopy because of concerns for potential morbidity, safety and unknown utility. We sought to determine the safety and utility of restaging mediastinoscopy before surgical resection. Methods A retrospective review was made of non-small cell lung cancer patients who underwent mediastinoscopy with a complex mediastinum, defined as any or all of the following: previous mediastinoscopy or induction chemotherapy or mediastinal radiation. Results Seventy-five patients underwent mediastinoscopy including 15 redo mediastinoscopies. In the non-redo group, 9 patients received induction chemotherapy, 16 received induction chemoradiotherapy ( 50 Gy), and 6 received radiation alone. Two were aborted owing to fibrosis. Stations 4L, 4R, and 7 were accessed in 84% of patients, with confirmed nodal tissue in 88%. There was 1 azygos vein injury that required urgent thoracotomy and 2 recurrent nerve injuries. Resection ensued in 63 patients: 53 with negative mediastinoscopy, 8 with microscopic nodal metastases, and the 2 aborted cases. In patients with negative mediastinoscopy, 5 had N2 disease at thoracotomy: 3 in stations 4 and 7 and 2 in nodal stations inaccessible by mediastinoscopy. The sensitivity was 71%, specificity was 100%, and negative predictive value was 91%. Conclusions In experienced hands, mediastinoscopy in a complex mediastinum is safe. Preclusive mediastinal fibrosis is rare. Expected lymph node stations can be accessed, and the results strongly correlate with postresection pathology. Mediastinoscopy is valuable to evaluate the nodal response to therapy in the setting of combined modality therapy.