Since conditional survival analysis provides better estimates of survival time at each followup, we assessed changes in conditional intravesical recurrence-free survival rates after radical nephroureterectomy. We also sought to determine how the impact of well-known risk factors evolves with time, particularly in patients with localized upper tract urothelial carcinoma.Materials and Methods:
We identified 364 patients with Ta-3N0M0 localized upper tract urothelial carcinoma who underwent open or laparoscopic radical nephroureterectomy at 1 of our 3 institutions. Conditional intravesical recurrence-free and cancer specific survival rates were calculated using the Kaplan-Meier method. The changing impact of parameters on intravesical recurrence with time was assessed by multivariate Cox regression analysis.Results:
Intravesical recurrence after radical nephroureterectomy was detected in 176 patients (48.4%) and 93 (25.5%) died of localized upper tract urothelial carcinoma. Five-year intravesical recurrence-free and cancer specific survival rates after surgery were 41.5% and 72.9%, respectively. Based on 1, 2, 3 and 4-year survivorship the 5-year conditional intravesical recurrence-free survival rate increased from 41.5% to 60.5%, 73.4%, 79.5% and 96.7%, respectively. The 5-year conditional cancer specific survival rate also improved from 72.9% to 78.4%, 85.4%, 90.9% and 95.5% at 1, 2, 3 and 4 years, respectively. The effects of well-known predictive factors on estimated conditional survival decreased with time for intravesical recurrence. In contrast, the impact of T2 or lower pathological stage and laparoscopic radical nephroureterectomy sustained statistical power with time.Conclusions:
Conditional survival analysis revealed that the probability of intravesical recurrence-free survival increased with time in patients with localized Ta-3N0M0 upper tract urothelial carcinoma after radical nephroureterectomy. Patients with T2 or lower T stage who undergo laparoscopic radical nephroureterectomy may be recommended for longer followup to detect subsequent intravesical recurrence.