ObjectiveTo investigate the clinicopathological characteristics and prognosis of young patients with non-small cell lung cancer (NSCLC).MethodsA total of 5320 patients with primary NSCLC from 2008 to 2014 were included and then divided into four groups according to their age, ie. a young group (≤ 45 years), a middle-young group (46 - 60 years), a middle-old group (61 - 75 years) and an old group (≥76 years). The clinicopathological manifestation and overall survival (OS) of the patients among the different age groups were compared.ResultsThe patients aged 45 years or younger accounted for 12.1% of all NSCLC cases. The proportions of females, never-smokers and adenocarcinoma were 49.9%, 65.9% and 74.0% in the young group, higher than those in the other three age groups (P<0.001 for all). And the proportion of Ⅲ/Ⅳ stage tumor was 84.3% in the young group, just less than that in the old group (87.9%; P<0.001). Patients in the young group were more likely to receive surgery (30.5%) and chemotherapy (38.9%), and got comparatively favorable OS compared with the patients in other age groups (P>0.05 for all).ConclusionsNSCLC occurring in young population is not rare. Young patients with NSCLC have unique clinicopathological characteristics, with more females, never-smokers and adenocarcinomas. Young patients with NSCLC may choose aggressive treatment approaches, such as surgery and chemotherapy, thus get a comparatively favorable prognosis.