Global Cancer Burden in Adolescents and Young Adults Based on Human Development Index and Income Status

Background: Cancer incidence (CI) and mortality vary significantly among countries and are impacted by numerous factors including the country's income and human development index (HDI). Cancer mortality (CM) in the adolescent and young adult (AYA) population, the age group of 15 - 39 years, has seen minimal improvement over the past few decades. Our study aims to identify disparities in this group and analyze the influence of income and HDI on these outcomes. Methods: We utilized the GLOBOCAN database estimates of incidence and mortality for year 2022 in 185 countries or territories for 36 cancer types to analyze the trends in crude rate of CI and crude rate of CM. Results: Globally, in 2022, an estimated 1.32 million new cases of cancer and 379,273 deaths were reported among individuals aged 15-39 years. The CM-to-CI ratios for countries with very high, high, medium, and low HDI were 16.6, 1:4.4, 1: 2.2, and 1:1.9, respectively. Similarly, based on the income level of countries, the CM-to-CI ratios were observed to be 1:8.6 for high-income, 1:4.8 for upper-middle-income, 1:2.3 for lower-middle-income, and 1:1.7 for low-income nations. Conclusion: Countries with a higher HDI and income levels experienced a notably higher incidence of cancer. However, the mortality rates were inversely related to the income and HDI. Mortality-to-incidence (CM:CI) ratios were alarmingly higher in countries with lower income and lower HDI. Introducing age-specific reforms and programs for the understudied AYA population in low to middle-income countries can have a significant impact on reducing CM globally.