Renal Function After Nephron-sparing Surgery Versus Radical Nephrectomy: Results from EORTC Randomized Trial 30904

BackgroundIn the European Organization for Research and Treatment of Cancer (EORTC) randomized trial 30904, nephron-sparing surgery (NSS) was associated with reduced overall survival compared with radical nephrectomy (RN) over a median follow-up of 9.3 yr (hazard ratio: 1.50; 95% confidence interval [CI], 1.03–2.16).ObjectiveTo examine the impact of NSS relative to RN on kidney function in EORTC 30904.Design, setting, and participantsThis phase 3 international randomized trial was conducted in patients with a small (≤5 cm) renal mass and normal contralateral kidney who were enrolled from March 1992 to January 2003.InterventionPatients were randomized to RN (n = 273) or NSS (n = 268).Outcome measurements and statistical analysisFollow-up estimated glomerular filtration rates (eGFR; milliliters per minute per 1.73 m2) were recorded for 259 subjects in the RN arm and 255 subjects in the NSS arm. Percentages of subjects developing at least moderate renal dysfunction (eGFR <60), advanced kidney disease (eGFR <30), or kidney failure (eGFR <15) were calculated for each treatment arm based on the lowest recorded follow-up eGFR (intent-to-treat analysis).Results and limitationsWith a median follow-up of 6.7 yr, eGFR <60 was reached by 85.7% with RN and 64.7% with NSS, with a difference of 21.0% (95% CI, 13.8–28.3); eGFR <30 was reached by 10.0% with RN and 6.3% with NSS, with a difference of 3.7% (95% CI, –1.0 to 8.5); and eGFR <15 was reached by 1.5% with RN and 1.6% with NSS, with a difference of –0.1% (95% CI, –2.2 to 2.1). Lack of longer follow-up for eGFR is a limitation of these analyses.ConclusionsCompared with RN, NSS substantially reduced the incidence of at least moderate renal dysfunction (eGFR <60), although with available follow-up the incidence of advanced kidney disease (eGFR <30) was relatively similar in the two treatment arms, and the incidence of kidney failure (eGFR <15) was nearly identical. The beneficial impact of NSS on eGFR did not result in improved survival in this study population.RegistrationEORTC trial 30904; ClinicalTrials.gov identifier NCT00002473.