Disparities in the incidence, mortality and disability-adjusted life years of 33 early-onset cancer groups globally, 2012-2021: a systematic analysis

The global cancer burden is rising, with early-onset cancers becoming more prevalent. We aimed to investigate the burden, trend and population disparity in 33 early-onset cancers from 2012 to 2021. In 2021, there were 2.65 million new early-onset cancer cases excluding non-melanoma skin cancer (NMSC), resulting in 0.99 million deaths and 50.7 million DALYs. Breast, tracheal, bronchus and lung (TBL), cervical, colon and stomach cancers were the leading causes of DALYs. The DALY rate for early-onset cancer excluding NMSC changed from 65.7 million in 2012 to 67.0 million in 2021, with an estimated annual percentage change (EAPC) of -0.49%. While the DALY rate plateaued for females, it decreased by -0.95% for males. Ten of 33 cancer groups exhibited an EAPC > 0. The high SDI quintile had 1,100 DALYs per 100,000 caused by early-onset cancers excluding NMSC, with the highest declining trend in DALY and mortality rates, while the high-middle SDI quintile had the highest early-onset mortality rates. Rising trends in cancer incidence and mortality were especially notable among females in the middle, low-middle, and low SDI quintiles.The global burden of early-onset cancer differs significantly by SDI quintile and gender. The increasing burden across multiple cancer groups poses a significant public health challenge. The rising burden of multiple cancer types is alarming, highlighting the need for increased policy support and targeted medical assistance to address the disparities in their impact.