Predicting risk of multiple levels of recurrence and progression after initial diagnosis of nonmuscle-invasive bladder cancer in a multisite, community-based cohort.

BACKGROUND: Nonmuscle-invasive bladder cancer (NMIBC) has heterogeneous recurrence and progression outcomes. Available risk calculators estimate recurrence and progression but do not predict the recurrence stage or grade, which may influence downstream treatment. The objective of this study was to predict risk-stratified NMIBC recurrence and progression based on recurrence tumor classification and grade. METHODS: In total, 2956 patients with NMIBC (