Risk factors associated with recurrence of surgically resected node-positive non-small cell lung cancer

The aim of this study was to identify risk factors for recurrence in non-small cell lung cancer (NSCLC) patients with lymph node metastases after surgical resection.

We reviewed 66 consecutive patients with surgically resected NSCLC who had pathologically proven positive lymph nodes (pN1 or pN2). All patients underwent a preoperative 2-[(18)F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) evaluation. We analyzed the recurrence-free survival (RFS) and recurrence-free proportion (RFP) according to the clinicopathological factors.

A total of 27 patients were pathologically N1 and 39 were N2. The 5-year overall survival rate and the RFS rate were 47.2 and 27.7 %, respectively. The cut-off values for the SUVmax of the tumor and the lymph node ratio (LNR) were determined to be 6.5 and 0.12, respectively, using a receiver operating characteristics curve analysis. Both univariate and multivariate analyses revealed three significant independent factors for RFS: namely, the SUVmax of the tumor, the LNR, and the use of adjuvant chemotherapy. Only the SUVmax was an independent significant predictor of the RFP.

Both the SUVmax and the LNR can serve as prognostic factors for patients with pN + NSCLC. Our study suggests that the LNR could be a stronger prognostic factor than the N classification of the TNM system and the SUVmax may predict recurrence in node-positive NSCLC patients.