Unilateral renal cell carcinoma with coexistent renal disease: a rare cause of end-stage renal disease

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.

Renal cell carcinoma as a cause of end-stage renal disease in the United States: patient characteristics and survival

BACKGROUND

The patient characteristics and mortality associated with renal cell carcinoma (RCC) as a cause of end-stage renal disease (ESRD) have not been characterized for a national population.

METHODS

An historical cohort study of renal cell carcinoma (RCC) was conducted from April 1, 1995, to December 31, 1999. Included were 360,651 patients in the United States Renal Data System (USRDS) who were initiated on ESRD therapy with valid causes of ESRD.

RESULTS

Of the study population, 1646 patients (0.5%) had RCC. The mean age of patients with RCC was 66.8 +/- 14.6 years versus 61.3 +/- 16.4 years for patients with other causes of ESRD (P < 0.01 by Student t test). The unadjusted 3-year survival (censored at the date of renal transplantation) of patients with RCC during the study period was 23% versus 36% in all other patients [adjusted hazard ratio (AHR), 1.10, 95% confidence interval (CI) 1.02-1.19, P = 0.019 by Cox regression]. However, patients with RCC who underwent nephrectomy (bilateral or unilateral) had significantly better survival compared to RCC patients who did not (AHR, 0.73, 95% CI, 0.63-0.85, P < 0.01), and their survival was not significantly different in comparison with nondiabetic ESRD patients. Bilateral nephrectomy (vs. unilateral) was not associated with any difference in adjusted mortality.

CONCLUSION

Among patients with ESRD, the demographics of those with RCC were similar to those of patients with RCC in the general population. Overall, patients with RCC had decreased survival compared to patients with other causes of ESRD; those who underwent nephrectomy had significantly better survival than those who did not, with survival comparable to patients with nondiabetic ESRD.