Global Epidemiologic Trends of Early-Onset Cancers From 1990 to 2021 and Projection to 2040

Early-onset cancer (EOC), defined as cancer occurring in individuals age 15-49 years, represents a growing global health burden. This study aims to assess the epidemiologic trends of EOC from 1990 to 2021 and project future incidence and mortality trends up to 2040.

Using data from the Global Burden of Disease (GBD) 2021 study, we analyzed the age-specific incidence rate (AsIR) and death rate (AsDR) per 100,000 patient-years for 31 cancer types across 204 countries. Statistical modeling, including the two sample t test, was done to estimate the standard deviations among each group, which is plugged in the denominator to compute the statistic. Autoregressive integrated moving average and exponential smoothing state space were employed for forecasting future trends.

In 2021, there were approximately 23.6 million new EOC cases and 0.99 million deaths globally. The highest AsIRs were observed in breast, nonmelanoma skin, and cervical cancers, with the highest AsDRs seen in breast and lung cancers in 2021. Although AsIR has increased globally, AsDR has declined from 1990 to 2021. EOC disproportionately affected women, particularly in high-income countries. Risk factor analysis highlights obesity, tobacco use, and dietary patterns as key contributors to EOC burden. Projected analysis till 2040 revealed relatively stable AsIR and declining AsDR for overall EOCs.

The increasing global burden of EOC underscores the need for targeted strategies. Regional disparities highlight the importance of health care access in mitigating EOC mortality. Healthy lifestyle could reduce the burden of EOC.