Prognostic factors after surgical resection of N1 non-small cell lung cancer

Non-small cell lung carcinoma (NSCLC) with N1 involvement is associated with 5-year survival rates ranging from 7% to 55%. Numerous factors have been independently reported to explain this heterogeneous prognosis, but their relative weight on long-term survival is unknown.

Patients who underwent surgical resection for NSCLC in two French centers from 1993 to 2010 were prospectively recorded and retrospectively reviewed. The overall survival (OS) of patients undergoing first-line surgery for pN1 disease was analyzed according to the type of extension, number of metastatic LN, number and anatomic location of metastatic stations.

The study group included 450 patients (male 80.2%, mean age 63.3 ± 9.9 years, 5-year overall survival 46%). The number of metastatic station was 1 in 340 (75.6%, single-station disease) and ≥2 in 110 patients (24.4%, multi-station disease). The number of metastatic stations was correlated with the number of metastatic LN (p < .001), and associated with adverse OS (p = .0014). The presence of intralobar metastatic LN (station 12-13-14) was associated with a mechanism of direct extension (p < .001), but did not impact OS (p = .71). The location of metastatic stations was of prognostic significance only in case of multi-station disease, with hilar (station 10) involvement being associated with adverse OS (p = .005). The 110 patients with multi-station pN1 disease and the 134 patients operated on for single-station pN0N2 (skip-N2) disease during the study period yield comparable outcome (p = .52).

In patients with resected pN1 NSCLC, the number of metastatic stations and their location in case of multi-station disease have a prognostic value.