Racial disparities in secondary metastasis in patients with bladder cancer: A 5-year National Inpatient Sample study.

671 Background: Bladder cancer is one of the most common cancers globally, with significant variations in disease outcomes observed across racial groups. Secondary metastasis plays a critical role in determining disease prognosis and overall survival in bladder cancer patients. However, racial disparities in the metastatic progression of bladder cancer remain underexplored. This study aims to investigate how race influences the patterns of metastasis in bladder cancer patients using a large national database. Methods: A retrospective analysis of the National Inpatient Sample (NIS) from 2016 to 2020 was performed to identify adults diagnosed with bladder cancer using ICD-10 codes. Patients were categorized based on the presence of metastasis. Multivariable logistic regression models were used to assess the impact of race on secondary metastasis to key organ systems, including the lung, liver, bone, and brain, while adjusting for potential confounders. Caucasians were used as the reference group, and statistical significance was defined as p-values ≤ 0.05. Results: The study cohort included 411,360 patients with bladder cancer, of whom 66,805 (16.2%) had secondary metastasis. The mean age of patients with metastasis was significantly lower (71.00 years, 95% CI: 70.78–71.22) compared to those without metastasis (74.02 years, 95% CI: 73.90–74.14) (p < 0.001). Racial disparities were observed, with African American patients having higher odds of lung metastasis (OR 1.23, 95% CI: 1.11–1.38, p < 0.001) and liver metastasis (OR 1.18, 95% CI: 1.05–1.33, p = 0.005). Asian patients were more likely to develop bone metastasis (OR 1.29, 95% CI: 1.13–1.47, p < 0.001) and brain metastasis (OR 1.46, 95% CI: 1.03–2.09, p = 0.036). Other factors associated with higher metastasis risk included radiation therapy (OR 3.71, 95% CI: 2.16–6.38, p < 0.001), while comorbidities like diabetes (OR 0.64, p < 0.001) and hypertension (OR 0.86, p < 0.001) were associated with lower odds of metastasis. Conclusions: This study highlights significant racial disparities in the metastatic progression of bladder cancer, with African American and Asian patients showing higher odds of metastasis to key organ systems compared to Caucasians. These findings underscore the need to consider racial differences in the clinical management and treatment strategies for bladder cancer patients. Further research is required to explore the underlying causes of these disparities and their impact on long-term survival.