Prognostic significance of the lymph node involvement around the main bronchus in the therapy of non-small cell lung cancer

Introduction

Non-small cell lung cancer (NSCLC) N1 and N2 disease represent a heterogeneous group of patients with variable long term survival. Some studies showed prognostic differences between the intralobar and extralobar N1 disease. Therefore many authors designated metastases around the main bronchus as the intermediate group (group 7, 10, 11 R/L).

The aim of our study was to investigate the tumor related, prognostic significance of nodal metastasis in the intermediate group when compared to single station N2 disease and/or to skipping metastasis.

Patients and Methods

From 1990 to 2007, a total of 850 patients underwent surgical resection for NSCLC: 252 (30%) had either N1 or N2 disease. We retrospectively evaluated 231 (95,8%) hospital survivors who underwent complete resection with mediastinal lymph node dissection. According to the extent of the lymph node involvement 110 patients (47%) where included in the intermediate group.

Results

The 5-year survival rate of patients with N1 and N2 diseases was 45% vs. 37%. The survival rate was not significantly different between the intralobar vs. extralobar N1 disease and/or the intermediate group (46%, 43% and 43%, n.s.). Subcarinal (7) and/or aorto-pulmonary window (5L) nodal metastases showed significantly better survival than in the paratracheal stations (2, 4R) (36% and 55% vs. 24%, p=0.002). Adenocarcinoma and the right side tumor location where associated with extended intermediate group involvement (p=0.003). The 5-year survival rate in the patients with left skipping metastasis was significantly different than on the right side (50% vs. 35%, p=0.003).

Conclusion

The clinical significance of the intermediate group remains unclear. Their prognostic influence depends on type and extent of lymph node involvement, tumor histology and location.