Towards optimal pathologic staging of resectable non-small cell lung cancer.

Pathologic nodal staging is the most accurate means of determining prognosis of patients with resectable non-small cell lung cancer (NSCLC), but confusion prevails about the optimal pre-operative and surgical lymph node examination procedures for candidates of curative-intent resection. The landmark American College of Surgeons Oncology Group Z0030 trial revealed no difference in the survival of patients with clinical T1 or T2, N0 or N1 (hilar node-negative), M0 NSCLC who either had a fastidious, pre-defined systematic hilar and mediastinal lymph node sampling procedure, or who received a complete mediastinal lymph node dissection. We place the results of this major trial into a contemporary clinical practice context, and discuss problems associated with apparent misunderstanding of the lessons from this trial, especially in light of evidence of prevailing sub-optimal nodal examination practices. We also discuss evolving knowledge about the origin of the quality gap in pathologic nodal staging and the emerging literature on corrective interventions.