Renal function impairment below safety limits correlates with cancer specific mortality in localized renal cell carcinoma: results from a single center study

Abstract Background A recent multi-center study showed how estimated glomerular filtration rate (eGFR) and cancer specific mortality (CSM) are linearly and inversely related in organ-confined renal carcinoma (RCC), whenever the eGFR decreases below specific thresholds. We addressed our previous work limitations related to heterogeneity and missing data, and to explore the relationship between eGFR and CSM also in locally advanced RCC. Materials and methods All RCC patients treated with either partial or radical nephrectomy from 1990 to 2018 at a single institution and with complete data on renal function were included. eGFR was managed as a time-dependent variable. The relationship between eGFR and CSM was analyzed using a Fine and Gray’s multivariable competing risks framework. Subdistribution hazard ratios (SHR) were calculated accounting for deaths from other causes. Results Multivariable competing risks analysis showed a “piecewise” relationship between eGFR and CSM, with an inverse linear correlation for eGFR values below 85 ml/min. Below this breakpoint, a significant relationship existed between eGFR and CSM in both clinical (SHR 1.27, p Conclusions In patients undergoing surgery for stage I-II RCC, preservation of renal function over “safety limits” is protective from CSM.