Predominant global glomerulosclerosis in patients of upper urinary tract urothelial carcinoma with pre-existing renal function impairment is a predictor of poor renal outcomes.

BACKGROUND: Incidence of renal dysfunction and risks of progression to end-stage renal disease (ESRD) were reported higher in upper urinary tract urothelial carcinoma (UTUC) than in renal cell carcinoma (RCC) patients after unilateral nephrectomy. METHODS: Totally 193 renal cancer patients, including 132 UTUC and 61 RCC, were studied to clarify whether the pathological changes of the kidney remnant removed from nephrectomy and the clinical factors might predict the risk of ESRD. Renal tubulointerstitial (TI) score and global glomerulosclerosis (GGS) rate were examined by one pathologist and two nephrologists independently under same histopathological criteria. RESULTS: The glomerular filtration rates at the time of surgery were lower in UTUC than RCC groups (p < 0.001). Average GGS score and average TI rate were higher in UTUC than in RCC groups (p < 0.001; p < 0.001). Competitive risk factor analysis revealed that abnormal GGS rate not related to age, predominant in UTUC with pre-existing renal function impairment, was a histopathological predictor of poor renal outcomes (creatinine doubling or ESRD) within 5 years in UTUC patients. CONCLUSION: Pre-existing renal function and pathological change of kidney remnant in both UTUC and RCC have the value for prediction of renal outcomes.