American Urological Association Nonmuscle Invasive Bladder Cancer Risk Model Validation-Should Patient Age be Added to the Risk Model?

Abstract

We evaluated the AUA (American Urological Association)/SUO (Society of Urologic Oncology) nonmuscle invasive bladder cancer risk model to predict nonmuscle invasive bladder cancer recurrence and progression prior to death. We performed a retrospective analysis using electronic medical records and cancer registry data of patients with nonmuscle invasive bladder cancer in a multicenter United States patient population. We evaluated recurrence-free and progression-free survival according to the AUA/SUO nonmuscle invasive bladder cancer risk model. We then assessed discriminative performance with the c-index and compared the cumulative incidence of recurrence, progression and death across 4 age groups. We identified 1,297 patients with nonmuscle invasive bladder cancer. Median followup in the cohort was 3.2 years. The c-index of the AUA/SUO recurrence model was 0.62 and for progression it was higher at 0.77. Patients younger than 60 years had a 40% greater probability of recurrent nonmuscle invasive bladder cancer vs death while patients 84 years old or older had a 12% greater probability of death prior to recurrence at 5 years. This study was limited by its retrospective design. The AUA/SUO nonmuscle invasive bladder cancer risk model provides predictive performance of recurrence and progression similar to that of previous similar risk models, such as the models of the European Organization for Research and Treatment of Cancer, the Club Urológico Español de Tratamiento Oncológico and the National Comprehensive Cancer Network®. This work illustrates the need to consider age in predictive tools for clinicians who treat patients with nonmuscle invasive bladder cancer.