Young age increases the risk of lymph node positivity but improves prognosis in patients with bladder cancer treated via cystectomy: a population-based study

BACKGROUND: Age and lymph node positivity are significant prognostic indicators in patients with bladder cancer. This study aimed to investigate the impact of age on lymph node positivity and bladder cancer outcomes. METHODS: Patients with bladder cancer who underwent cystectomy with at least one lymph node examined between 2004 and 2015 were identified from the Surveillance, Epidemiology, and End Results database. Cochran-Armitage trend tests and logistic regression analyses were used to evaluate the association between age and lymph node positivity in all T stages. Multivariate Cox regression analysis was used to analyze the effect of age on overall survival (OS) and cancer-specific survival (CSS). RESULTS: Overall, 13,251 patients were identified, 648 of whom were under 50 years of age (4.89%). Lymph node positivity was negatively associated with increasing age in each stage except in non-invasive-muscular bladder cancer. In the multivariable analysis, age was an independent prognostic factor for OS and CSS in both the overall cohort and the lymph node positivity group. CONCLUSIONS: In patients with bladder cancer undergoing cystectomy, young age at diagnosis is associated with a higher risk of lymph node positivity and superior outcomes. These findings may guide clinicians in selecting suitable treatments, determining the aggressiveness of lymph node involvement, and predicting survival outcomes in patients of different ages.