Purpose: We identified risk groups in primary superficial bladder cancer according to progression, mortality and recurrence rates.
Materials and methods: The prognostic factors of progression, mortality and recurrence were identified by multivariate analysis in a cohort of 1,529 patients with primary superficial bladder cancer. Risk groups were designed by combining the relative risk of these prognostic factors. We performed survival analysis of progression, tumor mortality and recurrence by risk group using the Kaplan-Meier method. Relative risk in each group was calculated by Cox regression. We present timetables of progression, mortality and recurrence by risk group.
Results: Risk groups were classified as low-grade 1 stage Ta disease and a single grade 1 stage T1 tumor, intermediate-multiple grade 1 stage T1 tumors, grade 2 stage Ta disease and a single grade 2 stage T1 tumor, and high-multiple grade 2 stage T1 tumors, grade 3 stages Ta and T1 disease, and any stage disease associated with carcinoma in situ. Survival analysis of progression, mortality and recurrence revealed a statistically significant difference among the 3 risk groups. The rates of recurrence, progression and mortality were 37%, 0% and 0% in the low, 45%, 1.8% and 0.73% in the intermediate, and 54%, 15% and 9.5% in the high risk group, respectively. The relative risks of recurrence, progression and mortality in the low versus the intermediate and high risk groups were 1.37, 2.84 and 1, and 1.87, 24.76 and 14.69, respectively.
Conclusions: Risk group classification based on prognostic factors defines progression, mortality and recurrence rates in primary superficial bladder cancer. It may be useful for designing treatment and followup strategies.