Tsitsias T, Okiror L, Veres L, et al. - In patients suffering from NSCLC, researchers conducted this retrospective review to validate the proposed N descriptor revision on a large cohort of patients as well as to determine how tumor location can impact the distribution pattern of lymph node metastases. Experts analyzed a consecutive series of patients who underwent anatomical lung resections. Of 2,566 patients treated surgically, 448 (17.5%) had histologically verified lymph node metastases; 257 (57.4%) were found to have pN1 and 191 pN2. Analysis according to the novel proposal of the N subgroups N1a vs N1b vs N2a1 vs N2a2 vs N2b demonstrated that median survival OS (overall survival) was 41.7 vs 39.2 months vs 33.3 months vs 28.9 months vs 24.6 months. The independent prognostic factors for survival that were identified in the multivariate analysis were pathological N and the new proposed N classification. Based on the findings, it was concluded that N1 and N2 disease represent heterogeneous groups and need further classification. The number of N2 lymph node stations involved and the presence or not of N1 disease have to be incorporated into N staging because these translated to significant disparities in survival.