In this multicenter study, we compared SU and RNU in terms of overall survival (OS) and impact on postoperative renal function in patients with UTUC and a pre-operative eGFR < 90 ml/min/1.73m2 (overall mean pre-operative eGFR 54.9 ml/min/1.73m2), which is considered the cut-off for normal renal function. We analyzed only those patients with ureteral cancer in order to better standardize the population and strengthen the clinical impact of the study. Thus, 93 patients were included in the study with a median follow-up of 26 months. Although the SU and RNU groups had different pre-operative eGFR (SU > RNU), both the groups showed a non-significant worsening of the eGFR (SU: -4.0 ml/min/1.73m2, p = 0.239; RNU: -2.6 ml/min/1.73m2, p = 0.219) after surgery. Moreover, postoperative eGFR decrease was not significantly different between the two groups. These findings could partially depend on the high prevalence of pre-operative hydronephrosis in both the groups, which could suggest a poor pre-existing function in the operated renal unit with a low impact on the global post-operative eGFR.
On the other hand, our study confirmed the already known survival overlap between SU and RNU (five-year OS: 46.8 vs. 52.0%, respectively) also in patients with reduced pre-operative eGFR.
Although this is a multicenter study, the main limitation of this study is the small population, which largely depends on the infrequency of the disease.
Our study suggests that the type of surgery (SU vs. RNU) chosen for the treatment of ureteral cancer has a low impact on postoperative renal function and OS in patients with pre-operative eGFR < 90 ml/min/1.73m2. This is interesting because, in the case of UTUC, it is common practice to consider kidney-sparing surgery especially for patients in fair or poor health with already compromised global renal function, in order to preserve the residual functioning parenchyma (except in the presence of a clearly functionally excluded kidney). Therefore, if further confirmed, our study would suggest that the indication for kidney-sparing surgery for ureteral tumors should not be based on pre-operative global eGFR or driven by the goal of preserving residual renal function in these patients. In fact, the presence of preoperative hydronephrosis may suggest a compromised function of the kidney affected by the disease but it is also associated with a higher tumor stage and a worse prognosis. As a consequence, the indication for kidney-sparing surgery for UTUC should be primarily based on surgical and oncological risks.
Written by: Alberto Abrate, MD,1 Alchiede Simonato, MD1,2
- Department of Surgical, Oncological and Oral Sciences, Section of Urology, University of Palermo, Palermo, Italy
- Department of Surgery, Urology Unit, S. Croce e Carle Hospital, Cuneo, Italy
- Department of Surgical, Oncological and Oral Sciences, Section of Urology, University of Palermo, Palermo, Italy
- Department of Surgery, Urology Unit, S. Croce e Carle Hospital, Cuneo, Italy