Dynamic Prognostication Using Conditional Recurrence and Progression Estimates for Patients with Nonmuscle Invasive Bladder Cancer.

PURPOSE: Conditional estimates provide a dynamic prediction of outcomes but to our knowledge there are no data on nonmuscle invasive bladder cancer. We assessed changes in conditional recurrence and progression rates after transurethral resection of the bladder and explored the prognostic impact of established factors and risk groups with time. MATERIALS AND METHODS: We retrospectively analyzed data on 1,292 consecutive patients with newly diagnosed Ta/T1 bladder cancer who underwent transurethral resection of the bladder. Study end points were time to first recurrence and time to progression. RESULTS: The 2-year recurrence rate at baseline was 36%, which improved as a function of the time that patients were free of disease recurrence. After 6, 12, 24, 36 and 48 months the 2-year conditional recurrence rate improved to 31% (14% improvement vs baseline), 22% (39% improvement), 16% (56% improvement), 13% (64% improvement) and 11% (69% improvement), respectively. Comparably, conditional progression rates improved with increasing followup, although relative differences were less distinct. The prognostic impact of established factors and nonmuscle invasive bladder cancer risk groups progressively decreased with time and finally disappeared. However, bacillus Calmette-Guérin had a protective effect on progression even after 3 years. We provide tables with dynamic prognostic information at all analyzed time points. CONCLUSIONS: In patients with primary Ta/T1 bladder cancer recurrence and progression rates improve with time. The prognostic impact of established factors and risk groups decreases and finally disappears. The effect of bacillus Calmette-Guérin on progression is long-lasting. Conditional outcome estimates may improve patient counseling and individualize surveillance planning.