Increasing cancer-related mortality and demographic disparities in young adults in the United States between 1999 and 2020.

10569 Background: The global rise in cancer incidence in the young adult population (≤ 45 years), particularly in obesity-related cancers, is of growing concern. As the demographic afflicted by cancer expands beyond traditional boundaries, a nuanced understanding of the unique characteristics and challenges specific to young adults is imperative for developing interventions that address their distinct needs. In this study, we characterize cancer mortality rates in the young adult population to assess for emerging trends and cancer burden in the United States. Methods: The Centers for Disease Control database was queried for all underlying causes of death due to cancer (ICD 10 codes C00-C97) between 1999 and 2020. Malignancies that primarily affect the elderly, such as prostate and multiple myeloma, were excluded. Age-adjusted mortality (AAMR) rates per 100,000 people were extracted for adult patients between 25 and 44 years of age. AAMR was assessed by demographic and clinical variables, including race, geographic density, sex, and primary site. Joinpoint trend analysis was used to identify the presence of statistically significant temporal trends. Average annual percent change (AAPC) was considered statistically significant if p < 0.05. Results: Between 1999 and 2020, 366,478 cancer-related deaths occurred in young adults in the United States. The overall AAMR was 20.7, decreasing from 24.8 in 1999 to 17.5 in 2020 at a rate of -1.6% annually (p<0.05). However, increasing mortality was seen in a number of primary sites, including uterine cancer with an increase of 2.6% annually (p<0.05) and colorectal cancer with an increase of 0.8% annually (p<0.05). Overall AAMR was highest for non-Hispanic Black individuals at 28.3, 29% higher than the next highest group (non-Hispanic White) at 21.2 and almost double that of non-Hispanic Asians at 14.7. Individuals residing in rural populations experienced the highest AAMRs at 24.3 and the slowest rates of decrease at -1.6% annually (p<0.05), compared with urban individuals whose AAMR was 19.8 with a decrease of -1.9% annually (p<0.05). Primary sites with the highest AAMRs included breast (3.1), lung (2.1), and colorectal (1.8) cancers. Conclusions: The current study sheds light on the evolving landscape of cancer mortality among young adults in the United States. The overall decrease in age-adjusted mortality rates is promising, reflecting advancements in cancer care and prevention strategies. However, the alarming increase in mortality rates for specific cancer types, such as uterine and colorectal cancers, underscores the need for targeted interventions and heightened awareness, especially in at-risk populations. The identified racial and geographic disparities further emphasize the importance of implementing tailored approaches to address the unique challenges faced by diverse populations.