Differences in Bladder Cancer Diagnosis by Demographic Factors: A Simulation Modeling Analysis

Area of Science:

• Oncology
• Health Disparities Research
• Biostatistics

Background:

• Bladder cancer presents significant morbidity and mortality in the US, with projected 85,000 new cases and 17,400 deaths in 2025.
• Disparities exist, with Black patients and female patients more likely to be diagnosed at advanced stages compared to White and male patients, respectively.

Purpose of the Study:

• To investigate whether disparities in bladder cancer diagnosis rates by race and sex explain observed variations in stage at diagnosis.
• To project the potential impact of improved diagnosis rates on patient outcomes and life expectancy.

Main Methods:

• A state transition model was developed to simulate bladder cancer progression across four cohorts (Black males, Black females, White males, White females).
• Model parameters were calibrated using SEER 17 registry data (2015-2019) for incidence rates and stage distribution.
• Scenario analysis was conducted to assess the effect of equalizing diagnosis rates to those of White males.

Main Results:

• Lower diagnosis rates were identified in White females (HR=0.95), Black males (HR=0.80), and Black females (HR=0.56) relative to White males.
• Equalizing diagnosis rates to those of White males could increase life expectancy for a 65-year-old bladder cancer patient by 0.2 years (White females), 0.6 years (Black males), and 1.9 years (Black females).

Conclusions:

• Disparities in bladder cancer diagnosis rates by race and sex are key drivers of differences in stage at diagnosis.
• Targeted interventions to improve diagnosis rates hold significant potential for improving bladder cancer survival rates.