The Clinical And Prognostic Features Associated With Skip N2 Metastases In Patients With Lung Cancer

Objective:The metastatic extent of lymph nodes is an important prognostic factor in patients with lung cancer. Whether the skip N2 metastases (SN2) makes difference in prognosis compared with traditional N2 metastases remains unclear. We aimed to compare the clinical and prognostic features of skip N2 metastases with N1 metastases and traditional N2 metastases in patients with lung cancer, to deepen the understanding of SN2, and to help improve the staging criteria and treatment of patients with lung cancer.Method:We retrospectively evaluated lung cancer patients who underwent lobectomy with systematic lymphadenectomy from January 1st 2010 to March 1st 2013 in our department. We recorded the clinical and pathological materials of patients with SN2, N1 or traditional N2 metastases, and univariate and muticaritae logistic regression analyses were performed to. identify the risk factors for SN2 metastases. We also followed up all the included patients to calculate the 3-year overall survivals (OS) and 3-year recurrence-free survivals (RFS), which were compared between patients with SN2, N1 or traditional N2 metastases.Results:Among the lllpatients included in this study,22 patients were with SN2 metastases,28 patients with N1 metastases, and 61 patients with traditional N2 metastases. Peripheral lung cancer (Oddis ratio:5.63, p= 0.006) was identified as a risk factor for SN2 metastases by multivariate logistic regression analysis. The OS and RFS of patients with SN2 and N1 metastases were similar (3-year OS:54.6% vs.54.7%, p= 0.878; 3-year RFS:42.1% vs.48.5%,p= 0.775). However, patients with SN2 metastases had a better prognosis than those with traditional N2 metastases (3-year OS:54.7% vs. 40.7%, p=0.071; 3-year RFS:48.5% vs.22.2%, p= 0.048), with significant statistical differences in 3-year RFS.Conclusion:The clinical and prognostic features of SN2 metastases was similar compared with N1 or traditional N2 metastases in lung cancer patients. The prognosis of patients with SN2 metastases was similar to those with N1 metastases, and better than those with traditional N2 metastases. Large randomized controlled tails are needed to confirm the better prognosis of lung cancer patients with SN2 metastases.