title: Staging lymph node metastases from lung cancer in the mediastinum.
abstract: BACKGROUND
  The presence of tumor metastases in the mediastinum is one of the most important elements in determining the optimal treatment strategy in patients with non-small cell lung cancer. This review is aimed at examining the current strategies for investigating lymph node metastases corresponding to an "N2" classification delineated by The International Staging Committee of the International Association for the Study of Lung Cancer (IASLC).
  
  
  METHODS
  Extensive review of the existing scientific literature related to the investigation of mediastinal lymph node metastases was undertaken in order to summarize and report current best practices.
  
  
  CONCLUSIONS
  N2 disease is very heterogeneous requiring multiple modalities for thorough investigation. New research is now focusing on better identifying, defining, and classifying lymph node metastases in the mediastinum. Molecular staging and sub-classifying mediastinal lymph node metastases are being actively researched in order to provide better prognostic value and to optimize treatment strategies. Non-invasive imaging, such as PET/CT and minimally invasive techniques such as endobronchial and endoscopic ultrasound guided biopsy, are now the lead investigative methods in evaluating the mediastinum for metastatic presence.
authors.affiliation: Division of Thoracic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Mario D
authors.initials: MD
authors.lastname: Terán
authors.affiliation: Division of Thoracic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Malcolm V
authors.initials: MV
authors.lastname: Brock
keywords: Lung cancer; N2 disease; lymph node staging; mediastinal metastasis