Evaluation of Quantitative and Qualitative Renal Outcome Following Nephron Sparing Surgery

PURPOSE: Preservation of renal function after nephron-sparing surgery (NSS) is multifactorial and the impact of individual factors on it is still a debate. This prospective study investigates the impact of factors responsible for quantitative and functional outcome after NSS. PATIENTS AND METHODS: Fifty-two patients of localized renal mass (≤7 cm) were included in the study. A contrast-enhanced computed tomography abdomen was performed for characterization of tumor. Glomerular filtration rate (GFR) was calculated using Tc99m-diethylenetriamine pentaacetic acid (DTPA) scan and Cockcroft-Gault (CG) formula. All relevant intra- and peri-operative events were noted. Follow-up work up performed at 3 months. RESULTS: Overall, the mean ischemia time was 30.6 min, with 7.7% decrease in renal volume in the operated moiety. In follow-up, the total and ipsilateral GFR decreased. Change in renal parenchymal volume, total GFR by CG and DTPA, split GFR of tumor-bearing moiety was significant in follow-up. Size, stage, polar location of tumor, duration of surgery, type of ischemia, preoperative chronic kidney disease, and need of blood transfusion did not affect change in renal volume and function in the follow-up period. CONCLUSION: Renal parenchymal loss and duration of ischemia have impact on the follow-up renal function.