ObjectiveTo understand variations in clinical epidemiology of lung cancer and to help with early accurate diagnosis and treatment of lung cancer.MethodsThis research was based on the Lung Cancer Database of West China Hospital of Sichuan University. Clinicopathological data of inpatients with primary lung cancer from 2011 to 2018 was collected for analysis. Information regarding sex, age, smoking history, surgical resection modalities, TNM stage of tumor, and pathological subtypes was included.ResultsA total of 23 228 inpatients with primary lung cancer were included in this research. There were 1 932, 2 029, 2 162, 2 773, 2 975, 3 318, 3 993, and 4 046 patients in every single year from 2011 to 2018, respectively. The male-to-female ratio of patients had changed significantly from 2.00∶1 in 2011 to 1.34∶1 in 2018 (P<0.001). Statistically significant difference was found in age distribution of patients in different years, while elderly always accounted for the majority of all patients. More nonsmokers were among the group of lung cancer patients, the proportion of whom rose from 41.61% in 2011 to 52.47% in 2018 (P<0.001). The proportion of adenocarcinoma in all subtypes rose from 54.04% in 2011 to 71.73% in 2018, while the proportion of squamous carcinoma dropped from 29.04% to 17.67% simultaneously. From 2011 to 2018, the proportion of stage Ⅰ lung cancer rose from 15.68% to 40.79%. Patients with stage ⅠA1 accounted for 11.82% in 2018. In 2018, 60.78% of stage ⅠA patients had gone through surgical resection modalities, forming a stark contrast with the fact that only 26.48% of stage ⅠA patients adopted surgeries in 2011.ConclusionsFrom 2011 to 2018, the total number of lung cancer patients increased year by year. The proportions of female patients and nonsmokers rose significantly. Adenocarcinoma accounted for the highest proportion of all subtypes, followed by squamous cell carcinoma. There were more patients with early lung cancer and less with advanced lung cancer diagnosed, implying a gradual accumulation of weight on the early stages according to the TNM classification of lung cancer.