Kidney disease progression in patients of upper tract urothelial carcinoma following unilateral radical nephroureterectomy.

OBJECTIVES

To compare the renal outcomes in patients of unilateral renal cell carcinoma (RCC) with upper tract urothelial carcinoma (UTUC) following surgical resection of the tumor-bearing kidney, and to investigate the potential predictors in renal function decline.

PATIENTS AND

METHODS

In this retrospective cohort study, 319 RCC patients undergoing radical nephrectomy (RN) and 297 UTUC patients undergoing radical nephroureterectomy were recruited from a tertiary medical center between 2001 and 2010. Demographic data, co-morbidity, smoking habit, baseline estimated glomerular filtration rate (eGFR) calculated by chronic kidney disease-epidemiology equation, as well as tumor staging of RCC and UTUC, were recorded. The primary endpoint was serum creatinine doubling and/or end-stage renal disease (ESRD) necessitating long-term dialysis. Cox proportional hazard model and Fine and Gray's competing risk regression accounting for death were used to model renal outcome.

RESULTS

UTUC patients had a higher incidence rate of renal function deterioration than RCC patients did (15.01 vs. 2.68 per 100 person-years, p<0.001). In Cox proportional hazard model and Fine and Gray's competing risk regression, UTUC was significantly associated with increased risk of creatinine doubling and/or ESRD necessitating dialysis (hazard ratio, 3.13; 95% confidence interval, 2.01-4.87) as compared to RCC following unilateral RN. Nevertheless, our study is observational in nature and cannot prove causality.

CONCLUSIONS

UTUC per se is strongly associated with kidney disease progression as compared to RCC following unilateral nephrectomy. Further studies are needed to elucidate this association.