Impact of warm versus cold ischemia on renal function following partial nephrectomy.

INTRODUCTION: We evaluated renal function following partial nephrectomy with cold ischemia (CI) versus warm ischemia (WI). METHODS: Data were collected from 1,396 patients at six institutions who underwent partial nephrectomy for a renal mass with normal contralateral kidney to evaluate percent change in glomerular filtration rate (GFR) at 3-18 months. A multivariate linear regression model tested the association of percent change GFR with clinical, operative, and pathologic factors. RESULTS: A total of 874 patients (63 %) underwent PN with CI and 522 (37 %) with WI. All patients undergoing laparoscopic and robotic-assisted partial nephrectomy (n = 443) had WI, whereas 92 % of open partial nephrectomy patients (n = 953) had CI. The CI group had a lower mean baseline GFR (72 vs. 80 ml/min/1.73 m(2)), longer median ischemia time (33 vs. 29 min), and larger mean tumor size (3.2 vs. 2.9 cm) with more advanced pathologic stage (T1b-T3: 25 vs. 16 %) (all p values <0.001). Patients with CI and WI demonstrated 12.3 and 10.1 % reductions in renal function from baseline, respectively (p = 0.067). Increasing age, female gender, and increasing tumor size were associated with reduction in renal function (all p values <0.001). Neither renal hypothermia nor operative technique independently predicted reduced renal function. Sensitivity analyses limited to ischemia time >30 min, baseline estimated glomerular filtration rate <60 ml/min/1.73 m(2), or tumors >4 cm did not significantly alter the findings. CONCLUSIONS: Increasing age, female gender, and larger tumor size independently predict a decrease in renal function following partial nephrectomy with a normal contralateral kidney. Within the limitations of a non-randomized comparison, including lack of parenchymal preservation percentage, neither surgical approach (open or laparoscopic) nor presence of hypothermia appears to be associated with long-term renal function.

Chronic kidney disease before and after partial nephrectomy.

PURPOSE: We performed a multi-institutional retrospective cohort study to evaluate baseline renal function of patients who underwent partial nephrectomy for renal tumors, and determined rates of progression to higher stages of chronic kidney disease. MATERIALS AND METHODS: The Modification of Diet in Renal Disease study equation was used to estimate glomerular filtration rate. Preoperative and postoperative serum creatinine values were obtained from patients who underwent partial nephrectomy at 6 institutions with a normal contralateral kidney, and had baseline chronic kidney disease stage I (estimated glomerular filtration rate greater than 90 ml/minute/1.73 m(2)), II (estimated glomerular filtration rate 60 to 89 ml/minute/1.73 m(2)) or III (estimated glomerular filtration rate 30 to 59 ml/minute/1.73 m(2)). The end point was change in chronic kidney disease stage at long-term followup (3 to 18 months). Multivariate logistic and Cox regression models tested the association of newly acquired chronic kidney disease stage III or greater with pertinent demographic, tumor and surgical factors. RESULTS: For 1,228 patients with followup creatinine data at least 3 months after partial nephrectomy median baseline glomerular filtration rate was 74 ml/minute/1.73 m(2). At baseline 19%, 59% and 22% of patients had chronic kidney disease stage I, II and III, respectively. At long-term followup for patients with baseline chronic kidney disease stage I or II median postoperative glomerular filtration rate was 67 ml/minute/1.73 m(2) with 29% having progression to chronic kidney disease stage III or greater. Increasing age, female gender, increasing tumor size, clamping of the renal artery and vein, and lower preoperative estimated glomerular filtration rate were independently associated with newly acquired chronic kidney disease stage III or greater. The presence of comorbid conditions such as coronary artery disease, diabetes mellitus or hypertension did not independently predict an increased risk of higher chronic kidney disease stage. CONCLUSIONS: Chronic kidney disease stage III or greater will develop postoperatively in approximately a third of patients with an estimated glomerular filtration rate greater than 60 ml/minute/1.73 m(2), and this progression is associated with definable demographic, tumor and surgical factors.

Chronic Kidney Disease Epidemiology Collaboration versus Modification of Diet in Renal Disease equations for renal function evaluation in patients undergoing partial nephrectomy.

PURPOSE: A novel equation, the Chronic Kidney Disease Epidemiology Collaboration, has been proposed to replace the Modification of Diet in Renal Disease for estimated glomerular filtration rate due to higher accuracy, particularly in the setting of normal renal function. We compared these equations in patients with 2 functioning kidneys undergoing partial nephrectomy. MATERIALS AND METHODS: We assembled a cohort of 1,158 patients from 5 institutions who underwent partial nephrectomy between 1991 and 2009. Only subjects with 2 functioning kidneys were included in the study. The end points were baseline estimated glomerular filtration rate, last followup estimated glomerular filtration rate (3 to 18 months), absolute and percent change estimated glomerular filtration rate ([absolute change/baseline] × 100%), and proportion of newly developed chronic kidney disease stage III. The agreement between the equations was evaluated using Bland-Altman plots and the McNemar test for paired observations. RESULTS: Mean baseline estimated glomerular filtration rate derived from the Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration equations were 73 and 77 ml/minute/1.73 m(2), respectively, and following surgery were 63 and 67 ml/minute/1.73 m(2), respectively. Mean percent change estimated glomerular filtration rate was -12% for both equations (p = 0.2). The proportion of patients with newly developed chronic kidney disease stage III following surgery was 32% and 25%, according to the Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration equations, respectively (p = 0.001). CONCLUSIONS: For patients with 2 functioning kidneys undergoing partial nephrectomy the Chronic Kidney Disease Epidemiology Collaboration equation provides slightly higher glomerular filtration rate estimates compared to the Modification of Diet in Renal Disease equation, with 7% fewer patients categorized as having chronic kidney disease stage III or worse.

Impact of ischemia on renal function after laparoscopic partial nephrectomy: a multicenter study.

PURPOSE: We assessed the influence of renal ischemia on long-term global renal function after laparoscopic partial nephrectomy in patients with 2 functioning kidneys in a large, multicenter cohort. MATERIALS AND METHODS: Collected data included demographic, clinical and surgical characteristics, tumor parameters and renal function outcomes at 4 institutions in a total of 401 patients with 2 functioning kidneys who underwent laparoscopic partial nephrectomy. Renal function was assessed in the immediate postoperative period (days 1 to 3) and at last followup (greater than 1 month) using the estimated glomerular filtration rate calculated by the 4-variable Modification of Diet in Renal Disease equation. Ischemia time and covariates were modeled on the percent change in the estimated glomerular filtration rate using linear regression. RESULTS: Median ischemia time was 29 minutes (IQR 22, 34). The postoperative change and the last (long-term) change in the estimated glomerular filtration rate were -16% and -11%, respectively. Median time to the last estimated glomerular filtration rate measurement was 13 months (IQR 6, 24). On multivariate analysis shorter ischemia and operative times, external or ureteral irrigation with cold saline and female gender were associated with less postoperative percent change in the estimated glomerular filtration rate. Smaller tumor size and absent diabetes were associated with less of a final percent change in the estimated glomerular filtration rate. Ischemia time was not associated with a percent change in the estimated glomerular filtration rate at last followup. CONCLUSIONS: Within the range of times in these series renal ischemia did not have a clinically significant impact on global renal function in patients with 2 functioning kidneys who underwent laparoscopic partial nephrectomy, as measured by the estimated glomerular filtration rate.

Advanced patient age is associated with inferior cancer-specific survival after radical nephroureterectomy.

OBJECTIVE: To assess the impact of patient age on outcomes after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC). PATIENTS AND METHODS: Data were collected on 1453 patients treated with RNU at 13 centres. Pathological slides were reviewed by dedicated genitourinary pathologists according to standardized criteria. Age at RNU was analysed both as a continuous and categorical variable (<50, n = 85; 50-59.9, n = 229; 60-69.9, n = 416; 70-79.9, n = 523; > or =80 years, n = 200). RESULTS Patients aged <50 years were less likely to have undergone previous ureteroscopy and to have a history of bladder cancer (P < or = 0.026). Advanced age was associated with infiltrative architecture and female gender (P < or = 0.003). Patients aged >70 years were less likely to undergo lymphadenectomy and to receive adjuvant chemotherapy (P < or = 0.026). In multivariable analyses, being older was associated with decreased all-cause (AC) survival (>60 years) and cancer-specific survival (CSS; >80 years) after controlling for the effects of standard pathological features (P < or = 0.006). However, addition of age did not improve the predictive accuracy of a base model that included standard pathological features for prediction of either disease recurrence, AC survival or CSS. CONCLUSIONS: Being older at the time of RNU was associated with decreased survival. This finding could be due to a change in the biological potential of the tumour cell, a decrease in the host's defence mechanisms, or differences in care patterns. Further work is needed to improve our understanding of UTUC outcomes in this growing segment of the population and to develop strategies to improve cancer control in the elderly.