In a recent National Cancer Database study, Black patients with nonmetastatic muscle-invasive bladder cancer (MIBC) were significantly less likely to receive standard curative treatment, even when accounting for clinical factors and institutions.4 Additionally, it is notable that racial differences exist in tumor biology,5-6 but high-quality genome-wide association studies have been stifled by underrepresentation of Black patients in publicly available genomic datasets.
The Veterans Affairs (VA) health system is the largest equal-access health system in the United States, and represents an ideal model to study the impact of access to care on outcomes. In their recent publication ‘Racial disparities in stage at bladder cancer diagnosis in the US Veterans Affairs healthcare system’, Bree et al. examined whether disparities in bladder cancer stage at diagnosis and stage-dependent survival exist in a racially admixed VA health system patient population.5
The investigators identified nearly 70,000 VA patients diagnosed with bladder cancer over a 20-year period from 2000 to 2020. The cohort was comprised of 11% Black patients, which were characterized as having lower median household incomes and higher rates of comorbid illness compared to White or Hispanic patients. In univariable analysis, Black patients presented with higher rates of MIBC (≥cT2) compared to White patients (OR 1.15, 95% CI 1.04-1.28). However, on multivariable analysis controlling for socioeconomic factors, there was no significant difference in stage at presentation between Black, White, and Hispanic patients. Notably, after controlling for stage at presentation, Black and White patients exhibited similar all-cause and bladder cancer-specific mortality, with Hispanic patients having a lower risk of mortality.
These data suggest that in an equal-access healthcare system, there exist similar stage distribution at initial patient presentation as well as similar survival outcomes between White and Black patients with bladder cancer after controlling for clinical and socioeconomic factors. These data corroborate previous reports that up to 40% of excess bladder cancer mortality exhibited by Black patients can be explained by factors related to care access, including insurance status, education, income, and distance to a hospital.5
Despite due emphasis being placed on identifying inequalities in cancer outcomes based on sociodemographic factors, the root etiology of such inequalities remains poorly understood. Moving forward, we must be committed to broad inclusion of racially diverse patients in bladder cancer clinical trials and genomic studies to inform whether biologic differences contribute to therapeutic efficacy. While identifying sociodemographic inequalities in our healthcare systems are of utmost importance, this merely represents the initial step towards implementation of material change in healthcare access and delivery.
Written by:
- Patrick J. Hensley, MD, Department of Urology, University of Kentucky College of Medicine Lexington, KY, USA
- Stephen B. Williams, MD, Division of Urology, University of Texas Medical Branch Galveston, TX, USA
- Siegel RL, Giaquinto AN, Jemal A. Cancer statistics, 2024. CA Cancer J Clin. 2024 Jan-Feb;74(1):12-49. doi: 10.3322/caac.21820. Epub 2024 Jan 17. Erratum in: CA Cancer J Clin. 2024 Mar-Apr;74(2):203. doi: 10.3322/caac.21830. PMID: 38230766.
- Scosyrev E, Noyes K, Feng C, Messing E. Sex and racial differences in bladder cancer presentation and mortality in the US. Cancer. 2009 Jan 1;115(1):68-74. doi: 10.1002/cncr.23986. PMID: 19072984.
- Yee DS, Ishill NM, Lowrance WT, Herr HW, Elkin EB. Ethnic differences in bladder cancer survival. Urology. 2011 Sep;78(3):544-9. doi: 10.1016/j.urology.2011.02.042. Epub 2011 Jul 22. PMID: 21782222; PMCID: PMC3710780.
- Washington SL 3rd, Neuhaus J, Meng MV, Porten SP. Social Determinants of Appropriate Treatment for Muscle-Invasive Bladder Cancer. Cancer Epidemiol Biomarkers Prev. 2019 Aug;28(8):1339-1344. doi: 10.1158/1055-9965.EPI-18-1280. Epub 2019 May 15. PMID: 31092404; PMCID: PMC6679737.
- Nyame YA, Baker KK, Montgomery B, Grivas P, Redman MW, Wright JL. Racial and sex differences in tumor genomics in urothelial carcinoma. Urol Oncol. 2023 Nov;41(11):456.e1-456.e5. doi: 10.1016/j.urolonc.2023.06.020. Epub 2023 Jul 21. PMID: 37481462.
- Vantaku V, Amara CS, Piyarathna DWB, Donepudi SR, Ambati CR, Putluri V, Tang W, Rajapakshe K, Estecio MR, Terris MK, Castro PD, Ittmann MM, Williams SB, Lerner SP, Sreekumar A, Bollag R, Coarfa C, Kornberg MD, Lotan Y, Ambs S, Putluri N. DNA methylation patterns in bladder tumors of African American patients point to distinct alterations in xenobioc metabolism. Carcinogenesis. 2019 Nov 25;40(11):1332-1340. doi: 10.1093/carcin/bgz128. PMID: 31284295; PMCID: PMC6875901.
- Cole AP, Fletcher SA, Berg S, Nabi J, Mahal BA, Sonpavde GP, Nguyen PL, Lipsitz SR, Sun M, Choueiri TK, Preston MA, Kibel AS, Trinh QD. Impact of tumor, treatment, and access on outcomes in bladder cancer: Can equal access overcome race-based differences in survival? Cancer. 2019 Apr 15;125(8):1319-1329. doi: 10.1002/cncr.31926. Epub 2019 Jan 11. PMID: 30633323.