Abstract 3591: Global burden and trends in cancer incidence and mortality among young adults

Abstract Background: Increasing cancer incidence among young adults has been reported for several types of cancers, primarily in certain high-income countries. However, there is a lack of comprehensive examination of the global burden and trends in cancer incidence and mortality among young adults. Methods: We presented estimated numbers of cancer cases, cancer deaths, age-standardized incidence, and mortality rates per 100, 000 people among young adults (YAs, ages 25-49 years) for all cancers combined and 35 cancer sites in 185 countries and 20 UN regions using GLOBOCAN 2022. We further quantified trends in age-standardized incidence (ASIR; 52 countries) and age-standardized mortality (ASMR; 62 countries) for the top five incident cancers (female breast, cervix uteri, thyroid, colorectum, and trachea, bronchus and lung cancers) among YAs over the most recent decade by estimating average annual percent change (AAPC), using the Cancer Incidence in Five Continents (CI5; 2008-2017) and WHO mortality data (2011-2020; thyroid mortality data was not available), respectively. Results: In 2022, an estimated 2.9 million cancer cases and 962, 000 cancer-related deaths occurred in YAs worldwide, corresponding to 108.1 cases per 100, 000 people per year and 35.9 deaths per 100, 000 people per year. Globally, ASIR and ASMR were higher in women than men (143.7 vs. 73.5 for incidence; 40.0 vs. 32.0 for mortality). By UN region, ASIR per 100, 000 people was highest in Australia-New Zealand (185.7) and lowest in South Central Asia (72.5), while ASMR per 100, 000 was highest in Eastern Africa (55.9) and lowest in Northern Europe (21.9). For the most recent 10 years, increases in ASIRs were observed for thyroid cancer (AAPC, 2.5-19.6%) in 27 countries, for colorectal cancer (AAPC, 1.2-11.5%) in 20 countries, for female breast cancer (AAPC, 0.7-5.9%) in 17 countries, and for cervix uteri cancer (AAPC, 1.8-15.7%) in 4 countries. Increases in ASMR were observed for colorectum cancer (AAPC, 0.6-8.0%) in 13 countries, for female breast cancer (AAPC, 0.9-4.8%) in 11 countries, and for cervix uteri cancer (AAPC, 2.1-4.7%) in 6 countries. Incidence and mortality both increased in YAs for female breast cancer in Czechia, ovarian cancer in the Republic of Korea, cervix uterine cancer in the Netherlands, and colorectum cancer in Australia, Canada, Chile, and the USA. Trachea, bronchus and lung cancers ASIR and ASMR decreased in 24 (AAPC, -1.5 to -11.3%) and 47 (AAPC, -2.0 to -11.4%) countries among YAs, respectively. Conclusions and Relevance: The burden and trends in cancer among young adults vary significantly by sex and region. Rising incidence and mortality rates for multiple cancer types across the world underscore the need for renewed attention to cancer prevention efforts and improvements to cancer surveillance systems targeting this often overlooked age group. Citation Format: Kieran Patrick Kelly, Yejun Son, Nikita Sandeep Wagle, Dong Keon Yon, Ahmedin Jemal, Hyuna Sung. Global burden and trends in cancer incidence and mortality among young adults [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3591.