Patterns and trends in incidence, survival, and treatment among patients with early-onset lung cancer in the U.S.: A population-based study.

Abstract

e22517 Background: Lung cancer is the second leading cause of cancer-related deaths among young adults. An in-depth investigation into the demographic distribution and temporal trends in early-onset lung cancer (EOLC) incidence and survival, as well as treatment patterns, could help monitor the cancer burden, identify high-risk populations, and develop effective screening and prevention strategies. Methods: This serial cross-sectional study used data from the U.S. Cancer Statistics (USCS) and the Surveillance, Epidemiology, and End Results (SEER) program. EOLC refers to lung cancer diagnosed in individuals aged 20-49 years. USCS database (2001-2019) was used for demographic description and incidence estimation. SEER-17 registries database (2000-2019) was used for survival estimation and treatment patterns examination. Age-adjusted incidence rate per 100,000 population and cancer-specific survival were reported. Changes in rates were assessed with average annual percentage change (AAPC) using Joinpoint regression. Results: There were 4,086,435 lung cancer cases recorded between 2001 and 2019 in the U.S. (USCS: 53.3% male; median age of 70 years). EOLC accounted for 4.1% (169,132) of all lung cancer cases and was more common among females, non-Whites, with higher adenocarcinoma and advanced-stage diagnoses. During this period, the incidence of EOLC decreased from 9.0 to 4.5 per 100,000 population (APC, -4.2; P < 0.001). EOLC incidence continued to decrease across all demographic groups, except for young people aged 20-29. The rate of decline was faster among men than women, blacks than whites, squamous carcinoma than adenocarcinoma, and distant disease than localized disease. The historical higher incidence among young men vs. young women and among blacks vs. whites have been reversed in recent years. A consistent increase in survival rates of EOLC across all demographic groups from 2001 to 2017 (SEER-17) was observed. Despite the increases were more pronounced among men than women and among black individuals than white individuals, gender and racial disparities persisted. EOLC patients received more intensive treatment than late-onset patients. Still, 12.1% of EOLC cases were not treated, and this was most common among black individuals and those with distant disease. Treatment patterns for EOLC have not undergone significant changes in recent decades. Of note, the proportion of untreated patients has not decreased during the study period. Conclusions: EOLC was an uncommon type of disease with distinctive clinical features in the U.S. Substantial decreases in incidence and improves in survival were observed, whereas major treatment pattern remained relatively stable.