BACKGROUND: Unexpected N2 involvement occurs in approximately 100small-cell lung cancer (NSCLC) and patients' prognostic factors remain unclear. The aim of this study was to evaluate prognostic factors in these patients. METHODS: From January 2002 to December 2012, we retrospectively analyzed data of 550 patients with NSCLC with preoperative negative, but pathologic positive N2 involvement, who underwent anatomical lung resection and hilo-mediastinal lymphadenectomy, obtained from 6 institutions. An established prognostic factor panel and N2-type involvement were correlated to overall (OS), cancer-specific (CSS), and disease-free survival (DFS) using multivariate Cox Regression model. The following lymph node patterns were analyzed: number of resected nodes (RNs), metastatic nodes (MNs), ratio between MNs and RNs (NR), N2 subgroups proposed for the eighth TNM edition, and lobe-specific versus nonspecific metastasis. RESULTS: Regarding our cohort, 419 patients were staged IIIA (T1-2N2), 131 IIIB (T3-4 N2), 113 pT1, 306 pT2, 94 pT3, and 37 pT4; 5-year OS, DFS, and CSS were 34.1 20.1 and 64.6 respectively. Independent prognostic factor for OS, in the multivariable analysis, were as follows: NR textless17P = .009), proposed N2 classification subgroups (P = .014), age textless66 (P textless .001), and pT (P = .005); for DFS: NR textless17P = .003), adjuvant treatment (P = .026), and pT (P = .026); and for CSS: NR textless17P = .008), grading (P = .001), and adjuvant treatment (P textless .001). CONCLUSION: Our study confirms that adjuvant therapy is fundamental and NR, in patients with unexpected N2 involvement, has a strong prognostic factor. In particular, a NR cutoff value of 17 DFS, and CSS in patients with NSCLC.
|Journal||Clinical Lung Cancer|
|Publication status||Published - Sep 1 2020|