PurposeThe aim of this prospective randomized trial was to assess the influence of the sequence of pulmonary vessel ligation, during anatomic resection, on long term survival in patients with NSCLC. Material/MethodsThis prospective randomized study included 385 patients treated surgically with lobectomy or pneumonectomy and standard lymphadenectomy between 1999 and 2003. Patients were randomly assigned to either primary ligation of the pulmonary artery or arteries (group A – 215 patients) or of the pulmonary vein or veins (group V – 170 patients). Patients were excluded if the sequence of vessel ligation was affected by technical difficulties or anatomic limitations. Univariate and multivariate analyses included: the sequence of vessel ligation, age, gender, tumor histology, stage (TNM), and cause of death (cancer related or non-cancer related). ResultsMedian follow-up was 63 months. The groups were comparable regarding gender, histology, type of resection, and T, N, and overall stage. Overall, 5-year survival reached 50% in group A and 54% in group V (p = 0.82) and did not differ significantly in cancer related and non-cancer related deaths (p = 0.67 and p = 0.26, respectively). Univariate analysis identified higher T and N factors, advanced stage, pneumonectomy, male sex, and older age as negative prognostic factors. Multivariate analysis demonstrated that age, T3–4 disease, and nodal involvement were associated with inferior survival. ConclusionsThe sequence of pulmonary vessel ligation during anatomic resection for non-small cell lung cancer does not significantly affect long-term survival.