Presentation Authors: Shigeta Keisuke*, Eiji Kikuchi, Masayuki Hagiwara, Takayuki Abe, Koichiro Ogihara, Ryuichi Mizuno, Mototsugu Oya, Tokyo, Japan
Introduction: Currently, there is no concrete evidence that supports an appropriate surveillance duration for detecting intravesical recurrence (IVR) after radical nephroureterectomy (RNU). Our specific aim is to create more meaningful and individualized surveillance durations for detecting subsequent IVR after RNU in upper tract urothelial carcinoma (UTUC) survivors.
Methods: We identified 714 non-metastatic UTUC patients who underwent RNU. The patients were stratified by pathologic T stage and chronological age. The hazard rate (HR) transition of IVR development and non-UTUC death were estimated by using parametric models for time-to failure with Weibull distributions.
Results: At a median follow-up of 6.5 years, a total of 307 (43.0%) patients developed subsequent IVR. The overtime risk transition of IVR was classified with pT stage and the risk of overall death was stratified with chronological age. The HR of developing IVR showed the highest with â‰¤pT1, followed by pT2, pT3, and pT4 at baseline (e.g. â‰¤pT1 patients had 12.7 times higher HR of developing IVR than pT4 patients), but the risk of IVR showed a decline in all pT stages as the survival time increased after RNU (e.g. the HR of IVR in â‰¤pT1 patients decreased to 6.2 times higher than those of pT4 patients at ten years after RNU). On the other hand, the HR of overall death was higher in the elderly stage (e.g. age >80 showed 6.5 times higher HR of overall death than those of age â‰¤60 at baseline), and they increased over time in all age groups (e.g. the HR of overall death in age >80 patients increased to 10.3 times higher than those of age â‰¤60 at ten years after RNU). Based upon the Weibull model estimate, we calculated the age-specific and stage-specific time points when the risk of overall death exceeds the risk of IVR. Specifically, among patients with pT2N0M0, the HR of overall death exceeded the HR of developing IVR at 3 years after RNU for older than 80 and 6 years for 71-80, but the HR of IVR remained greater for more than 10 years at age 70 years or younger.
Conclusions: Our study demonstrated that â‰¤pT1 and pT2 UTUC patients have a higher risk for developing IVR than pT3 and pT4, but the risks gradually decrease over time and the risk of overall death overcomes the risk of IVR as the survival years increase after RNU. However, especially for younger UTUC patients with lower pT stages, 10 years or more follow-up duration may be recommended for detecting subsequent IVR after RNU.