Effect of examining lymph nodes count on mortality risk in resected T1 non-small cell lung cancer

Abstract

Abstract OBJECTIVES This study aims to estimate the effect of the examined lymph node count on the cancer-related mortality risk and non-cancer-related mortality risk in patients with resected T1 non-small cell lung cancer. METHODS Patients diagnosed as primary T1 non-small cell lung cancer between 2000 and 2017 were extracted from the Surveillance, Epidemiology and End Results database. Patients were divided into two groups according to the examined lymph node count cutoff value, which was calculated based on overall survival outcomes. Propensity score matching was used to equalize the differences in baseline characteristics between groups. RESULTS A total of 38,242 resected T1 non-small cell lung cancer patients were extracted from the database with the examined lymph node count cutoff value of eight. After PSM, 27,676 patients were included in this study. Examining ≥ 8 ELNC was associated with a more accurate assessment of lymph nodes metastasis and significantly improving the prognosis. These trends remained consistent in subgroup analysis by histology type. In competing risk mode, examining ≥ 8 LNs could significantly reduce the risk of death from lung cancer, risk of death from chronic obstructive pulmonary disease, and risk of death from cardiac diseases. In the subgroup analysis, these trends were consistent. CONCLUSIONS Given the mortality risk associated with lung cancer, chronic obstructive pulmonary disease, and cardiac diseases, at least 8 LNs should be examined in surgery for T1 non-small cell lung cancer.