What is the role of surgery in potentially resectable N2 non-small cell lung cancer?

### Key messagesStage III/N2 non-small cell lung cancer (NSCLC) describes the metastatic spread of a primary tumour to the ipsilateral mediastinal lymph nodes. It is a heterogeneous disease stage ranging from unsuspected N2 disease only detected by intraoperative lymph node sampling during surgical resection of the primary tumour to conglomerate, bulky and invasive N2 disease that cannot be resected. For unresectable N2 NSCLC concurrent chemoradiotherapy is widely accepted as the standard of care in the context of appropriate physiological reserve.1–3 Between these two ends of the spectrum sit those patients with discrete and potentially resectable N2 disease. The optimal treatment strategy in this patient group is keenly debated and a number of guidelines from the UK, Europe and America have made recommendations.1–3 The aim of this article is to review these guidelines and provide an interpretation of their recommendations as a guide to clinicians involved in the care of patients with potentially resectable N2 NSCLC. A summary of the key randomised controlled trials (RCTs) in resectable N2 NSCLC that form the basis of these …