A serial cross-sectional analysis of 523,763 US deaths with secondary lung malignancy (C78.0) recorded on death certificates from 1999 to 2024 found that age-adjusted mortality rates declined through 2008, then increased 0.75% annually to reach 11.38 per 100,000 in 2024, the highest recorded. Relative increases were steepest in adults aged 25–34 years (70.5%) and those ≥85 years (62.5%); geographic variation shifted, with the West moving from lowest to highest regional mortality. The authors note that the rise may reflect changes in survival, metastatic disease burden, detection, or documentation practices rather than true disease occurrence.
Why it is interesting: The trend reversal after 2008 and marked age-specific disparities raise questions about whether improved primary cancer survival is increasing metastatic disease incidence, whether death-certificate practices have changed, or whether detection has improved—findings that bear directly on how we interpret early-onset cancer trends and on mortality attribution methods.