Trends, disparities, and forecasts of osteosarcoma mortality in the United States, 1999-2035.

BACKGROUND: Osteosarcoma-related mortality in the United States remains a concern, particularly in the context of population aging. METHODS: We used the CDC WONDER Underlying Cause of Death database (1999-2023) to identify osteosarcoma deaths (ICD-10 C40-C41). Crude mortality rates and age-adjusted mortality rates (AAMRs) per 100,000 (standardized to the 2000 U.S. population) were calculated for individuals aged ≥ 15 years and stratified by sex, age group, race/ethnicity, census region, and urban-rural classification. Temporal trends, annual percent change (APC), and average annual percent change (AAPC) were estimated using Joinpoint regression. Future mortality trends through 2035 were projected using autoregressive integrated moving average (ARIMA) and exponential smoothing state-space (ETS) models. RESULTS: From 1999-2023, the overall AAMR increased from 0.52 to 0.59 per 100,000 (AAPC 0.67; 95% CI 0.34-0.99). Men consistently had higher mortality than women. Mortality was strongly age-graded, peaking among adults aged ≥ 85 years, whereas rates in those aged 15-24 remained essentially stable. Non-Hispanic White individuals and residents of the South had the highest AAMRs, while the Northeast showed the lowest. Nonmetropolitan areas exhibited higher AAMRs than metropolitan areas, despite faster recent increases in cities. Forecasts based on ARIMA and ETS models indicate that AAMR will continue to rise through 2035. CONCLUSIONS: Osteosarcoma mortality in the United States has risen modestly over the past 25 years, with deaths concentrated among older adults and clear disparities by sex, race/ethnicity, region, and urban-rural residence. Specific initiatives are essential to rectify these discrepancies and enhance early detection and treatment, especially among high-risk populations.