Kidney function following partial or radical nephrectomy for renal cell carcinoma: a population-based study.

OBJECTIVE: The aim of this retrospective study was to compare kidney function in a population-based cohort of renal cell carcinoma (RCC) patients after partial (PN) or radical nephrectomy (RN). MATERIAL AND METHODS: Forty-four consecutive RCC patients who had undergone PN in Iceland between 2000 and 2010 were compared with 44 controls matched for tumour, node, metastasis (TNM) stage who had undergone RN during the same period. Estimated glomerular filtration rate (eGFR) and survival were calculated, and predictors of chronic kidney disease (CKD) were evaluated with multivariate analysis. RESULTS: In 16 cases (36%), PN was performed for imperative reasons (single kidney, decreased kidney function or bilateral kidney tumours) but 28 patients had a normal contralateral kidney. The groups were similar regarding preoperative eGFR, median follow-up and TNM stage, but age and American Society of Anesthesiologists (ASA) score were significantly higher in the RN group. Six months after surgery, eGFR was significantly higher in the PN group. By multivariate analysis, RN contributed negatively to eGFR 6 months after surgery (-12.6 ml/1.73 m², p < 0.001) and increased the risk of new-onset CKD (odds ratio = 3.07, 95% confidence interval 1.03-9.79, p = 0.04), compared to PN. At median follow-up of 44 months, no patients in either group had a recurrence of RCC. The 5-year overall survival (Kaplan-Meier) was 100% and 65% in the PN and RN groups, respectively (log-rank test, p < 0.001). CONCLUSION: eGFR was significantly lower after RN, and these patients were three times more likely to develop new-onset CKD. These findings suggest that PN successfully preserves kidney function compared to RN, with good oncological outcome and survival.