Prognostic factors for survival in patients with completely resected pN2 non-small-cell lung cancer.

Background: This study examined the incidence of pathologic N2 (pN2) non-small-cell lung cancer (NSCLC) and prognostic factors affecting survival of these patients.

Methods: A total of 119 patients who underwent surgery for NSCLC (lobectomy and pneumonectomy) between January 2008 and December 2016 were evaluated retrospectively. The patients with pN2 included in this study were assessed in two groups; single pN2 and multiple pN2.

Results: The most common type of resection was lobectomy (56.3%). Ninety-four patients (79%) received adjuvant therapy. Eighty-six patients (72.3%) had single-station pN2 and 33 (27.7%) had multiple pN2. The 5-year survival rates were 29.3% overall, 38.6% in single-station pN2, and 11% in multiple-station pN2 (hazard ratio [HR]: 0.581,  = .037). There was no statistically significant difference in 5-year survival rates between patients with pN1N2 and those with pN0N2 involvement (39.1% 37.1%) ( = .625). Not receiving adjuvant therapy was associated with poor survival prognosis (HR: 8.2  < .001). The 5-year survival rate was 36.2% among patients with pN2 involvement with 2 or more positive lymph nodes and 19.5% among those with fewer than 2 positive lymph nodes (HR: 0.83,  = .463).

Conclusions: The most significant prognostic factors associated with survival were pN2 status. Non-skip metastases (pN1N2) and positive lymph node count were not associated with prognosis.