Surgery for patients with persistent pathological N2 IIIA stage in non-small-cell lung cancer after induction radio-chemotherapy: the microscopic seed of doubt.

OBJECTIVE: The surgical treatment of residual N2 disease following induction radio-chemotherapy (IT) for locally advanced cIIIA-N2 non-small-cell lung cancer (NSCLC) is still debated. The long-term results after resection in a pN2 series are at the focus of this study.
METHODS: From January 1992 to December 2008, 161 consecutive pathologically proven Stage IIIA-N2 NSCLC patients underwent IT. Among these, 40 pN2s were included in this retrospective analysis. The associations between the mortality and the disease-free status with potential risk factors were explored by means of the Kaplan-Meier and Cox regression analysis.
RESULTS: Mean age and male/female ratio were 58.7 ± 9.7 years and 36/4, respectively. Twelve patients (30%) showed a clinical partial response and 28 (70%) showed stable disease. There was one (3%) perioperative death and four (10%) major complications. In the total group, the 3- and 5-year survival rates were 24.2% and 19.3%, respectively. The Cox regression analysis suggested that the macroscopic pN2 status proved to be a negative prognostic factor (hazard ratio (HR)=2.8, confidence interval (CI) 95%: 1.1-7.3; p=0.04). The recurrence rate flattened at 30.8% at the 3rd year. Furthermore, the bilobectomy-pneumonectomy group had a risk of relapse 6.9 times higher than the lobectomy group (CI 95%: 2.5-18.8; p < 0.001).
CONCLUSIONS: The persistence of disease at the N2 level after IT and surgery for cIIIa-N2 NSCLC does not exclude favorable outcome after resection, in particular in those patients with minor residual disease.