Trends in the Characteristics of Patients with Lung Cancer in Incheon, Republic of Korea: A Population-Based Study from the Incheon Cancer Registry

Background/Aims: This study aimed to analyze the changes in the demographic and clinical characteristics of patients with lung cancer in Incheon, South Korea from 2013 to 2020. By examining these trends, this study aimed to uncover regional patterns of lung cancer incidence and inform public health strategies and screening policy. Methods: A population-based sample of 1,152 patients with lung cancer was obtained from the Incheon Cancer Registry. Patient data included age, sex, smoking history, histology, clinical stage, and epidermal growth factor receptor (EGFR) mutation status. Histological subtypes were classified according to the International Classification of Diseases for Oncology, 3rd edition. Temporal trends in demographic and tumor characteristics were analyzed using the linear-by-linear association test. Results: The median age of patients with lung cancer was 70 years, with a significant increase in the proportion of patients aged ≤ 60 years (<i>p</i> < 0.001). The proportion of female patients slightly increased from 22.0% to 35.5% during the study period (<i>p</i> = 0.130). Adenocarcinoma was the predominant histological subtype (56.9%), with its proportion increasing to 62.7% by 2020 (<i>p</i> = 0.035). Early stage diagnoses (stage I) significantly increased over time (<i>p</i> < 0.001), whereas smoking history (<i>p</i> = 0.189) and EGFR mutation (<i>p</i> = 0.054) prevalence showed no significant changes. These trends were similar to those observed in the Korea Central Cancer Registry. Conclusions: The findings revealed significant demographic and clinical shifts in patients with lung cancer in Incheon, including an increasing proportion of older and female patients, increased early stage diagnoses, and growing adenocarcinoma prevalence. These trends underscore the need for tailored public health interventions, expanded low-dose computed tomography screening programs, and strategies targeting non-smoking-related risk factors to optimize lung cancer prevention and management.