Non-Cancer-Related Causes' Impact on Lung Cancer Survival: SEER Analysis

Abstract As lung cancer (LC) patients survive longer, non-cancer-related mortality risks are increasingly prominent, yet temporal trends and risk factors remain unclear. This study systematically evaluates standardized mortality ratios (SMRs) for non-cancer deaths and their temporal dynamics. We analyzed 371,177 lung cancer patients from tthe Surveillance, Epidemiology, and End Results (SEER) database (2000–2019), categorizing non-cancer-related deaths into six groups: infectious, diabetes, cardiovascular, respiratory, digestive, and others. SMRs were calculated, and Fine-Gray models assessed mortality risks. Non-cancer-related deaths rose significantly over time, increasing from 7.72% within 1 year to 53.97% beyond 5 years post-diagnosis (overall SMR = 2.24, 95% CI 2.22–2.26), surpassing cancer-specific mortality after 5 years. Cardiovascular (SMR = 4.85) and respiratory diseases (SMR = 3.56) were predominant, with peak non-cancer mortality at 1–5 years (SMR = 2.33). Multivariate analysis identified advanced age, male sex, advanced-stage cancer, and lack of active treatment as key risk factors. This mortality shift, driven by aging and treatment-related complications, underscores the need for multidisciplinary survivorship programs. Prioritizing cardiovascular monitoring, lifestyle interventions (e.g., smoking cessation), and structured follow-up for untreated patients may reduce preventable deaths. These strategies address critical gaps in long-term management, improving survival and quality of life for lung cancer survivors.