Urban-rural disparities in survival of Chinese esophageal squamous cell carcinoma: a cohort study of 133,064 cases

OBJECTIVE: To compare urban-rural disparities in overall survival of patients with esophageal squamous cell carcinoma (ESCC) in China and identify independent prognostic factors. METHODS: A retrospective cohort study including 133,064 ESCC patients diagnosed between 1973 and 2024 was conducted. Survival curves were estimated using the Kaplan-Meier method, and differences were tested by log-rank test. Univariate and multivariate Cox regression analyses were performed to identify prognostic factors. Propensity score matching (PSM) was applied to balance baseline characteristics between rural and urban groups. RESULTS: Overall survival was significantly better in rural patients than in urban patients (log-rank P < 0.001). Multivariate analysis showed that urban residence was an independent risk factor for poor prognosis (HR = 1.032, 95% CI: 1.001-1.064, P = 0.042). Significant urban-rural differences were observed in age, gender, smoking, alcohol intake, tumor differentiation, TNM stage, and treatment modality. Subgroup analysis revealed that the survival advantage of rural patients was more prominent in stage Ⅲ-Ⅳ disease. After 1:1 PSM, survival differences between urban and rural patients were no longer significant (P = 0.375). CONCLUSION: Rural residence is an independent favorable prognostic factor for ESCC, and its effect is mainly mediated by baseline clinicopathological characteristics, lifestyle factors, and treatment patterns. After adjusting for confounding factors, survival between urban and rural patients becomes comparable. These findings provide real-world evidence for risk stratification and individualized treatment of ESCC. Future studies are needed to explore the molecular mechanisms underlying urban-rural heterogeneity in ESCC.