En Bloc Resection of a Primary Tumor and Lymph Nodes in Non-Small-Cell Lung Cancer.

Purpose: We established a novel surgical procedure for resectable non-small-cell lung cancer (NSCLC), which involves resection of the affected lobe and regional lymph nodes without separation, namely en bloc surgery. We introduced the technical details and early and late outcomes by comparing them with those of conventional surgery.

Methods: We retrospectively analyzed patients who underwent lobectomy with hilar and mediastinal lymph node dissection for stages I-III NSCLC. A propensity score-matched analysis was performed based on demographic variables.

Results: Propensity score-matching yielded 317 pairs. En bloc surgery was not associated with a longer operation time, a higher amount of intraoperative bleeding, or a higher frequency of postoperative complications. The number of resected lymph nodes (P = 0.277) and frequency of N upstaging (P = 0.587) did not differ between the groups. However, en bloc surgery was associated with higher overall survival in comparison to conventional surgery (P = 0.012). According to a stratification analysis, the survival advantage of en bloc surgery over conventional surgery was remarkable in pathological N-positive disease (P = 0.005), whereas it disappeared in pathological N-negative disease (P = 0.147).

Conclusion: En bloc surgery is feasible and can be performed in patients with possible N-positive NSCLC.