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Objective: To assess recurrence-free survival (RFS) in patients with undetectable tumour-informed circulating tumour DNA (ctDNA) before radical cystectomy (RC) and evaluate if those who converted from detectable to undetectable ctDNA status after RC have similar RFS outcomes as those with persistently undetectable ctDNA status., Patients and Methods: Patients who underwent RC had prospectively and longitudinally collected tumour-informed ctDNA analyses during 2021-2023. ctDNA status was informed from the pre-RC specimen. The minimal residual disease (MRD) window was defined as the initial 90 days after RC. RFS was evaluated using the Kaplan-Meier method. Cox regression analysis was performed to find predictors of disease recurrence., Results: The cohort included 135 patients with 647 ctDNA analyses. The median (interquartile range [IQR]) age was 71 (63-77) years. Over a median (IQR) follow-up of 11 (7-18) months, 41 patients (30%) had a recurrence. Pre-RC undetectable ctDNA status was found in 54 patients (40%). The RFS rates at 6, 12, and 21 months were 98%, 93%, and 82%, respectively. Of 77 patients with undetectable ctDNA status at the MRD window available for conversion dynamics analysis, 43 had persistently undetectable ctDNA status (both at pre-RC and MRD window) and 31 converted from pre-RC detectable to MRD undetectable status (conversion group). The persistently undetectable group had significantly better RFS than the conversion group (log-rank, P < 0.001), with 12-month RFS rates of 97% vs 51%, and 18-month RFS rates of 88% vs 51%, respectively. On Cox multivariate analysis, only the conversion group status predicted disease recurrence., Conclusions: Patients with undetectable pre-RC ctDNA status have a favourable prognosis and may be candidates for treatment de-escalation. Those with persistently undetectable ctDNA had superior RFS compared to the conversion group. Pre-RC ctDNA status should be incorporated into trials examining ctDNA use in clinical decision-making., (© 2024 BJU International.)

Objective: To analyse surgical, functional, and mid-term oncological outcomes of robot-assisted nephroureterectomy (RANU) in a contemporary large multi-institutional setting., Patients and Methods: Data were retrieved from the ROBotic surgery for Upper tract Urothelial cancer STtudy (ROBUUST) 2.0 database, an international, multicentre registry encompassing data of patients with upper urinary tract urothelial carcinoma undergoing curative surgery between 2015 and 2022. The analysis included all consecutive patients undergoing RANU except those with missing data in predictors. Detailed surgical, pathological, and postoperative functional data were recorded and analysed. Oncological time-to-event outcomes were: recurrence-free survival (RFS), metastasis-free survival (MFS), cancer-specific survival (CSS), and overall survival (OS). Survival analysis was performed using the Kaplan-Meier method, with a 3-year cut-off. A multivariable Cox proportional hazard model was built to evaluate predictors of each oncological outcome., Results: A total of 1118 patients underwent RANU during the study period. The postoperative complications rate was 14.1%; the positive surgical margin rate was 4.7%. A postoperative median (interquartile range) estimated glomerular filtration rate decrease of -13.1 (-27.5 to 0) mL/min/1.73 m 2 from baseline was observed. The 3-year RFS was 59% and the 3-year MFS was 76%, with a 3-year OS and CSS of 76% and 88%, respectively. Significant predictors of worse oncological outcomes were bladder-cuff excision, high-grade tumour, pathological T stage ≥3, and nodal involvement., Conclusions: The present study contributes to the growing body of evidence supporting the increasing adoption of RANU. The procedure consistently offers low surgical morbidity and can provide favourable mid-term oncological outcomes, mirroring those of open NU, even in non-organ-confined disease., (© 2024 The Author(s). BJU International published by John Wiley & Sons Ltd on behalf of BJU International.)

Objectives: To compare the safety and efficacy of oral apixaban with that of injectable enoxaparin after robot-assisted radical cystectomy (RARC) for venous thromboembolism (VTE) thromboprophylaxis., Materials and Methods: We conducted a retrospective review of prospectively collected data for all RARC patients treated at our tertiary care centre between 2018 and 2022. The study included two groups: patients who were subject to a prospectively implemented protocol from October 2021 to the present, comprising a 21-day postoperative course of apixaban 2.5 mg twice daily after discharge, and patients treated prior to October 2021 who received enoxaparin 40 mg daily. Baseline demographics and clinical characteristics, such as VTE (defined as deep vein thrombosis and pulmonary embolism), were analysed. The primary outcome was incidence of symptomatic VTE confirmed with definitive imaging within 90 days of RARC. Secondary outcomes included major bleeding, complications, readmission, and mortality within 30 days postoperatively. Descriptive statistics included baseline patient characteristics, operative information and complications. Differences in baseline characteristics and postoperative data were compared between groups. Multivariate logistic regression was used to determine associations between variables and the primary outcome., Results: A total of 124 patients received apixaban and 250 patients received enoxaparin prophylaxis. Ten patients (2.7%) experienced a VTE within 90 days postoperatively (two [1.6%] apixaban group vs eight [3.2%] enoxaparin group; P = 0.5). After patient stratification into European Association of Urology risk groups, no statistically significant difference in VTE rates was seen between groups in the apixaban (2.7% high- + intermediate-risk group vs 1.1% low-risk group; P = 0.5) and enoxaparin cohorts (4.3% high- + intermediate-risk group vs 2.5% low-risk group; P = 0.5). On multivariate logistic regression, no variables were associated with the development of the primary outcome., Conclusion: Prophylaxis with apixaban and enoxaparin showed no statistically significant differences in VTE rates among RARC patients. Apixaban appears to be safe and effective for VTE prophylaxis after RARC., (© 2023 BJU International.)

Objectives: To prospectively analyse robotically administered transperitoneal transversus abdominis plane (robot-assisted transversus abdominis plane [RTAP]) compared with both ultrasonography-guided transversus abdominis plane (UTAP) and local anaesthesia (LA) with regard to pain control and narcotic use in patients undergoing robot-assisted prostatectomy (RARP) or robot-assisted partial nephrectomy (RAPN)., Subjects/patients and Methods: Patients undergoing RARP or RAPN were randomized in a single-blind 2:2:1 fashion to RTAP:UTAP:LA, with the study powered to evaluate superiority of UTAP to LA and non-inferiority of RTAP to UTAP. We compared time to deliver the block, operating room time, postoperative pain scores using the visual analogue scale, and intra-operative and postoperative analgesia consumption., Results: A total of 143 patients were randomized and received treatment. There was no significant difference in patient baseline characteristics. UTAP did not demonstrate superiority to LA in terms of pain control. RTAP and LA were faster to administer than UTAP (time to perform block 2.5 vs 2.5 vs 6.25 min; P &lt; 0.001). There was no difference in postoperative narcotic, acetaminophen, ketorolac or ondansetron requirements among the three groups (P &gt; 0.05). The study was terminated early due to the unexpected efficacy of LA., Conclusion: This study showed that UTAP and RTAP do not provide superior pain control to LA. The efficiency, effectiveness, and ease of administration of LA make it an excellent option for first-line therapy for postoperative analgesia., (© 2022 BJU International.)

Objective: To describe the natural history of untreated muscle-invasive bladder cancer (MIBC) and compare the oncological outcomes of treated and untreated patients., Patients and Methods: We utilised a database encompassing all patients with newly diagnosed bladder cancer in Stockholm, Sweden between 1995 and 1996. The median follow-up for survivors was 14.4 years. Overall, 538 patients were diagnosed with bladder cancer of whom 126 had clinically localised MIBC. Patients were divided into two groups: those who received radical cystectomy or radiation therapy, and those who did not receive any form of treatment. Multivariable Cox or competing-risks regressions were adopted to predict metastasis, overall survival (OS), and cancer-specific mortality (CSM), when appropriate. Analyses were adjusted for age at diagnosis, sex, tumour stage, clinical N stage, and treatment., Results: In all, 64 (51%) patients did not receive any definitive local treatment. In the untreated group, the median (interquartile range) age at diagnosis was 79 (63-83) vs 69 (63-74) years in the treated group (P < 0.001). Overall, 109 patients died during follow-up. At 6 months after diagnosis, 38% of the untreated patients had developed metastatic disease and 41% had CSM. The 5-year OS rate for untreated and treated patients was 5% (95% confidence interval [CI] 1, 12%) vs 48% (95% CI 36, 60%), respectively. Patients not receiving any treatment had a 5-year cumulative incidence of CSM of 86% (95% CI 75, 94%) vs 48% (95% CI 36, 60%) for treated patients. Untreated patients had a higher risk of progression to metastatic disease (hazard ratio [HR] 2.40, 95% CI 1.28, 4.51; P = 0.006), death from any cause (HR 2.63, 95% CI 1.65, 4.19; P < 0.001) and CSM (subdistribution HR 2.02, 95% CI 1.24, 3.30; P = 0.004)., Conclusions: Untreated patients with MIBC are at very high risk of near-term CSM. These findings may help balance the risks vs benefits of integrating curative intent therapy particularly in older patients with MIBC., (© 2019 The Authors BJU International © 2019 BJU International Published by John Wiley & Sons Ltd.)

Objective: To evaluate whether poor nutrition is associated with mortality in patients undergoing cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma (mRCC)., Patients and Methods: A multi-institutional review of prospective databases identified 246 patients meeting inclusion criteria who underwent CN for mRCC from 1993 to 2012. Nutritional markers evaluated were: body mass index <18.5 kg/m(2) , serum albumin <3.5 g/dL, or preoperative weight loss of ≥5% of body weight. Primary outcomes were overall (OS) and disease-specific survival (DSS). Secondary outcome was 'early mortality' defined as death at ≤6 months of surgery. Survival curves were estimated using the Kaplan-Meier product-limit method and multivariate analysis using logistic regression was used to test associations between nutritional markers and survival outcomes., Results: In all, 119 patients (median follow-up 17 months) were categorised as having any abnormal nutrition parameter (48%). Hypoalbuminaemia was the only independent predictor of OS and DSS (OS: median 8 vs 23 months, P < 0.001; DSS: 11 vs 33 months, P < 0.001). On multivariate analysis, hypoalbuminaemia remained a significant predictor of death for both overall [hazard ratio (HR) 2, 95% confidence interval (CI) 1.4-2.8; P < 0.001) and disease-specific mortality (HR 2.2, 95% CI 1.4-3.3; P < 0.001). Hypoalbuminaemia was also associated with early mortality (overall: P < 0.001 and disease specific: P = 0.002)., Conclusion: Patients with mRCC and hypoalbuminaemia undergoing CN have decreased OS and CSS, and increased risk of all-cause and disease-specific early mortality. As such, serum albumin may help risk stratify patients selected as candidates for CN. Furthermore, future work should evaluate whether nutritional depletion is a modifiable risk factor., (© 2014 The Authors. BJU International © 2014 BJU International Published by John Wiley & Sons Ltd.)

Objective: To examine the incidence of and risk factors for development of hyperlipidaemia in patients undergoing radical nephrectomy (RN) or partial nephrectomy (PN) for renal cortical neoplasms, as hyperlipidaemia is a major source of morbidity in chronic kidney disease (CKD)., Patients and Methods: We conducted a two-centre retrospective analysis of 905 patients (mean age 57.5 years, mean follow-up 78 months), who underwent RN (n = 610) or PN (n = 295) between July 1987 and June 2007. Demographics, preoperative and postoperative hyperlipidaemia were recorded. De novo hyperlipidaemia was defined as that ocurring ≥6 months after surgery in cases where laboratory values met National Cholesterol Education Program Adult Treatment Panel III definitions. The Kaplan-Meier method was used to assess freedom from de novo hyperlipidaemia. Multivariable analysis was conducted to determine the risk factors for de novo hyperlipidaemia., Results: There were no significant differences with respect to demographics, preoperative glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) (P = 0.123) and hyperlipidaemia (P = 0.144). Tumour size (cm) was significantly larger in the RN group vs the PN group (7.0 vs 3.7; P < 0.001). Significantly greater postoperative GFR <60 mL/min/1.73 m(2) was noted in the RN group (45.7 vs 18%, P < 0.001). Significantly, more de novo hyperlipidaemia developed in the RN group than in the PN group (23 vs 6.4%; P < 0.001). The mean time to development of hyperlipidaemia was longer for PN than for RN (54 vs 44 months; P = 0.03). Five-year freedom from de novo hyperlipidaemia probability was 76% for RN vs 96% for PN (P < 0.001). Multivariable analysis showed that RN (odds ratio [OR] 2.93; P = 0.0107), preoperative GFR <60 mL/min/1.73 m(2) (OR 1.98; P = 0.037) and postoperative GFR <60 mL/min/1.73 m(2) (OR 7.89; P < 0.001) were factors associated with hyperlipidaemia development., Conclusion: Patients who underwent RN had a significantly higher incidence of and shorter time to development of de novo hyperlipidaemia. RN and pre- and postoperative eGFR <60 mL/min/1.73 m(2) were associated with development of hyperlipidaemia. Further follow-up and prospective investigation are necessary to confirm these findings., (© 2014 The Authors. BJU International © 2014 BJU International.)

Objective: We evaluated survival outcomes of partial nephrectomy (PN) and radical nephrectomy (RN) for clinical T2 renal masses (cT2RM) controlling for R.E.N.A.L. nephrometry score., Patients and Methods: A two-centre study comprised of 202 patients with cT2RM who underwent RN (122) or PN (80) between July 2002 and June 2012 (median follow-up 41.5 months). Kaplan-Meier analysis compared overall survival (OS), cancer-specific survival (CSS) and progression-free survival (PFS) among the entire cohort and within categories of R.E.N.A.L. nephrometry score of ≥10 and <10. Association between procedure and PFS and OS was analysed using Cox-proportional hazard., Results: There were no significant differences between PN and RN in clinical T stage and R.E.N.A.L. nephrometry scores. For RN and PN, the 5-year PFS was 69.8% and 79.9% (P = 0.115), CSS was 82.5% and 86.7% (P = 0.407), and OS was 80% and 83.3% (P = 0.291). Cox regression showed no association between RN vs PN and PFS; a R.E.N.A.L. nephrometry score of ≥10 was associated with a shorter PFS (hazard ratio 6.69, P = 0.002). Kaplan-Meier analysis for RN vs PN showed no difference in PFS for entire cohort or within the R.E.N.A.L. nephrometry score categories of ≥10 and <10. The PFS was better for those with R.E.N.A.L nephrometry scores of <10 vs ≥10 (P < 0.001) and for cT2a vs cT2b tumours (P = 0.012). OS was no different between cT2a and cT2b tumours; patients with R.E.N.A.L. nephrometry scores of ≥10 were more likely to die from disease (P < 0.001) or any cause (P < 0.001) vs those with R.E.N.A.L. nephrometry scores of <10., Conclusions: PN may be oncologically effective for cT2RM. A R.E.N.A.L nephrometry score of ≥10 is negatively associated with OS among cT2RM compared with a score of <10 and provides additional risk assessment beyond clinical T stage. Further follow-up and prospective randomised investigation is requisite to confirm efficacy of PN for cT2RM., (© 2013 The Authors. BJU International © 2013 BJU International.)

Objective: To examine the association of renal morphology with renal function after partial nephrectomy (PN)., Patients and Methods: We conducted a multi-institutional retrospective analysis of 322 PNs performed between 2003 and 2011. The RENAL nephrometry score for each lesion was determined and the estimated glomerular filtration rate (eGFR) was calculated preoperatively and at last follow-up. We divided patients into two RENAL nephrometry score groups, low (<8) and high (≥8), and analysed and compared the outcomes of each group. The primary outcome was median change in eGFR between preoperative and last follow-up (ΔeGFR). The secondary outcome was eGFR <60 mL/min/1.73 m(2) at last follow-up. Multivariable analysis was conducted to evaluate the risk factors for eGFR <60 mL/min/1.73 m(2) at last follow-up., Results: The median (interquartile range) follow-up was 25.2 (13.5-39.3) months. Low (n = 165) and high (n = 157) RENAL score groups were well-matched for baseline eGFR. The median tumour size (4.2 vs 2.4 cm, P < 0.001) was greater for the high group. In all, 64% of the low and 88.2% of the high RENAL score group (P < 0.001) had decreased eGFR at last follow-up. Median eGFR was -7 for the low vs -13.8 mL/min/1.73 m(2) for the high group (P = 0.001); eGFR <60 mL/min/1.73 m(2) at last follow-up was 27.3% for the low vs 37.6% for the high group (P = 0.057). Linear regression analysis showed that for each 1-point increase in RENAL score, there was 2.5% decrease in eGFR (P = 0.002); for each 1-cm increase in tumour size, there was 1.8% decrease in eGFR (P = 0.013). Area under curve analyses showed no significant difference between RENAL score and tumour size for prediction of de novo eGFR <60 mL/min/1.73 m(2) (P = 0.920) and ΔeGFR ≥50% (P = 0.85). Multivariable analysis showed that increasing RENAL score (odds ratio [OR] 1.24, P = 0.046) and decreasing preoperative eGFR (OR 1.10, P < 0.001) were risk factors for eGFR <60 mL/min/1.73 m(2) at last follow-up., Conclusions: Increasing RENAL nephrometry score is an independent risk factor for eGFR <60 mL/min/1.73 m(2) after PN. RENAL nephrometry score may serve as an additional measure for risk stratification before PN, but further investigation is required., (© 2013 BJU International.)

Unlabelled: Study Type - Therapy (prospective cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Erectile dysfunction (ED) is a form of endothelial dysfunction that is prevalent in patients with chronic kidney disease (CKD). We hypothesized that partial nephrectomy (PN) would limit development of ED compared with radical nephrectomy (RN), primarily due to renal function preservation, and found that patients undergoing RN had significantly higher de novo ED compared with a contemporary, well-matched cohort undergoing PN; in addition to RN, hypertension, CKD and diabetes mellitus were associated with developing ED. To our knowledge, this is the first study demonstrating an increased risk of ED after RN compared with PN., Objectives: •  To evaluate prevalence and risk factors for development of erectile dysfunction (ED) in patients who underwent radical nephrectomy (RN) and partial nephrectomy (PN). •  ED is a form of endothelial dysfunction that is prevalent in patients with chronic kidney disease (CKD). PN confers superior renal functional preservation compared with RN; however, the impact on ED is unclear., Methods: •  This was a retrospective study of 432 patients (264 RN/168 PN, mean age 58 years, mean follow-up 5.8 years) who underwent surgery for renal tumours between January 1998 and December 2007. •  The primary outcome was rate of de novo ED postoperatively. Secondary outcomes included development of CKD (estimated GFR < 60 mL/min/1.73 m(2) ) and response to phosphodiesterase-5 inhibitors. •  Multivariate analysis was performed to determine risk factors for de novo ED postoperatively., Results: •  RN and PN groups had similar demographics and comorbidities. •  Tumour size (cm) was larger for RN (RN 7.0 vs PN 3.7, P < 0.001) and more preoperative ED existed in PN vs RN (P= 0.042). No differences were observed for preoperative CKD, hyperlipidaemia and diabetes mellitus. •  Postoperatively, higher rates of de novo ED (29.5% vs 9.5%, P < 0.001) and CKD (33.0% vs 9.8%, P < 0.001) developed in RN vs PN cohorts, respectively. •  Of men with ED, 63% responded to phosphodiesterase inhibitors, without significant difference between the two groups (P= 0.896). •  Multivariate analysis demonstrated de novo ED to be associated with RN (odds ratio [OR] 3.56, P < 0.001), hypertension (OR 2.32, P= 0.014), preoperative (OR 8.77, P < 0.001) and postoperative (OR 2.64, P= 0.001) CKD, and postoperative diabetes mellitus (OR 2.93, P < 0.001)., Conclusions: •  Patients undergoing RN had significantly higher de novo ED compared with a contemporary, well-matched cohort undergoing PN. In addition to RN, hypertension, CKD and diabetes mellitus were associated with developing ED. •  Further investigation on effects of surgically induced nephron loss on ED is requisite., (© 2012 BJU INTERNATIONAL.)

Objective: To examine the incidence of and risk factors for the development of anaemia and erythropoiesis-stimulation agent (ESA) treatment in patients undergoing radical nephrectomy (RN) and partial nephrectomy (PN) because anaemia is a significant cause of morbidity in chronic kidney disease., Patients and Methods: The study comprised a retrospective review of 905 patients (610 RN/295 PN; mean age, 57.5 years; mean follow-up, 6.4 years) who underwent surgery for renal tumours at two institutions from July 1987 to June 2007. Demographics, disease characteristics and pre- and postoperative (i.e. renal function, metabolic parameters, anaemia and ESA treatment) were recorded. Data were analyzed within subgroups based on treatment (RN vs PN). Multivariate analysis was conducted to determine the risk factors for developing anaemia after surgery., Results: Tumour size (cm) was significantly larger for RN (RN 7.0 vs PN 3.7; P < 0.001). No significant differences were noted with respect to demographics and preoperative anaemia (RN 16.4% vs PN 18.6%; P = 0.454) and ESA-treatment (RN 0.7% vs PN 1.4%; P = 0.499). After surgery, significantly less de novo anaemia (PN 4.1% vs RN 17.5%; P < 0.001) and ESA utilization (PN 2.7% vs RN 13.4%; P < 0.001) occurred in the PN cohort. Multivariate analysis showed that age ≥60 years (odds ratio, OR, 1.62; P = 0.008), African American ethnicity (OR, 2.30; P < 0.001), smoking (OR, 1.60; P = 0.013), glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) (OR, 4.09; P < 0.001), ≥1+ proteinuria (OR, 2.19; P < 0.03), metabolic acidosis (OR, 4.08; P = 0.007) and RN (OR, 2.58; P < 0.001) were significantly associated with de novo anaemia., Conclusions: Patients who underwent RN had a significantly higher prevalence of anaemia and ESA-treatment compared to a well-matched cohort that underwent PN. In addition to RN, age ≥60 years, African American ethnicity, history of smoking, GFR < 60 mL/min/1.73 m(2), proteinuria and metabolic acidosis were associated with developing anaemia., (© 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.)

Objective: To investigate efficacy of neoadjuvant tyrosine kinase-inhibitor therapy (TKI) before imperative nephron-sparing surgery (NSS), as NSS in patients with large locally advanced or centrally located tumours can be challenging, and TKI therapy might result in a reduction of primary tumour burden and increase the feasibility of NSS., Patients and Methods: This was a multicentre retrospective review and prospective pilot study of patients undergoing neoadjuvant sunitinib before planned NSS from February 2006 to February 2009. All patients underwent confirmatory biopsy for clear cell renal cell carcinoma. Patients received two 28-day cycles of sunitinib before NSS. Demographics/tumour characteristics, tumour response (by the Response Evaluation Criteria In Solid Tumors), outcomes and complications were analysed., Results: Twelve patients (seven men and five women; mean age 60.1 years, tumours on 14 renal units) were given TKI before NSS for imperative indications. The mean pretreatment tumour diameter was 7.1 cm; all patients had a decrease in size of the primary tumour after TKI, with a mean reduction in maximum diameter of 1.5 cm (21.1%). Four of 14 and 10 of 14 primary tumours had a partial response and stable disease after TKI. NSS was achievable in all 14 kidneys. Four patients had a concurrent metastasectomy. The mean warm ischaemia time was 22.5 min; postoperative dialysis was not required in any patients. Final pathology revealed negative tumour margins in all 14 tumours. The mean creatinine and estimated glomerular filtration rate (before/after NSS) were 1.34/1.40 mg/dL (P = 0.431) and 57.7/53.4 mL/min/1.73 m(2) (P = 0.475), respectively. At a mean follow-up of 23.9 months, 10 of the 12 patients were alive, one died from metastatic RCC and none required dialysis. Three of the 14 renal units developed delayed urinary leaks, all in patients who also received postoperative sunitinib. All leaks resolved with conservative measures., Conclusions: Neoadjuvant TKI followed by NSS is safe and feasible, with all patients achieving a reduction in maximum tumour diameter, and with NSS being achievable with negative margins and with no requirement for postoperative dialysis. Further investigation is required., (© 2010 THE AUTHORS. JOURNAL COMPILATION © 2010 BJU INTERNATIONAL.)

Objective: to examine incidence of and risk factors for the development of nephrolithiasis in patients treated with radical nephrectomy (RN) or partial nephrectomy (nephron-sparing surgery, NSS)., Patients and Methods: the study comprised a single-centre review of 749 patients treated with RN or NSS from August 1987 to June 2006. Demographics, medical and stone history, metabolic variables and postoperative stone events were recorded. Data were analysed within subgroups based on treatment (RN vs NSS). Multivariate analysis was used to identify risk factors for postoperative stone formation., Results: in all, 499 patients had RN and 250 had NSS (mean age 57.9 years; mean follow-up 6.3 years). There were no significant differences in their demographic factors, but tumours were significantly larger in RN (P < 0.001). There was no significant difference in preoperative urinary pH < 6.0 or stone history. Significantly fewer patients after NSS than RN formed calculi (NSS 1.6% vs RN 8.4%, P < 0.001), developed hypobicarbonataemia (NSS 7.2% vs RN 12.8%, P= 0.020), and a urinary pH of <6.0 (NSS 11.2% vs RN 19.4%, P= 0.004). Multivariate analysis showed that RN (odds ratio 18.18), postoperative urinary pH < 6 (15.63), previous stone disease (13.7), age <60 years (7.33, all P < 0.001), body mass index ≥ 30 kg/m(2) (3.26, P= 0.033), male gender (2.67, P= 0.039), and hypobicarbonataemia (2.46, P= 0.034) were significantly associated with the development of postoperative calculi., Conclusions: patients undergoing RN have a significantly higher incidence of postoperative nephrolithiasis than a well-matched cohort undergoing NSS. In addition to RN, male sex, urinary pH < 6.0, hypobicarbonataemia, history of stone disease, obesity, and age <60 years were significantly associated with postoperative stone formation.

Objective: To investigate the incidence of and risk factors for developing chronic renal insufficiency (CRI), proteinuria and metabolic acidosis (MA) in patients treated with radical nephrectomy (RN) or nephron-sparing surgery (NSS)., Patients and Methods: We retrospectively reviewed 749 patients (mean age 57.7 years; mean follow-up 6.4 years) who had RN or NSS for renal tumours between July 1987 and June 2006 at our institution. The demographics and outcomes were analysed and recorded. The primary outcome variable was the development of an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m(2), with secondary outcomes being the development of a serum creatinine level of > or =2.0 mg/dL, MA (serum bicarbonate <22 mmol/L), and proteinuria (> or =1+ on dipstick testing). Multivariate logistic regression (MV) was used to identify risk factors for developing an eGFR of <60 mL/min/1.73 m(2), a creatinine level of > or =2.0 mg/dL and MA., Results: Of the 749 patients, 499 had RN and 250 NSS; there were no significant demographic differences between the groups. After surgery a significantly greater proportion of the RN than the NSS group had a low eGFR (44.7% vs 16.0%, P < 0.001), MA (12.8% vs 7.2%, P = 0.02), proteinuria (22.2% vs 13.2%, P = 0.003) and elevated creatinine (14.2% vs 8.4%, P = 0.022). MV showed that diabetes mellitus (odds ratio 8.96, P = 0.002), RN (5.32, P < 0.001), hypertension (4.55, P = 0.003), a body mass index (BMI) of > or =30 kg/m(2) (3.51, P = 0.017), age > or =60 years (2.91, P = 0.015) and smoking (2.44, P = 0.014) were risk factors for developing a low eGFR; and that age > or =60 years (2.00, P = 0.019), diabetes mellitus (10, P < 0.001), hypertension (7.41, P = 0.002), smoking (5.29, P < 0.001) and RN (3.08, P < 0.001) were risk factors for developing an elevated creatinine level; and that being male (2.50, P = 0.019), age > or =60 years (3.13, P = 0.002), a BMI > or =30 (3.52, P < 0.001), RN (9.82, P < 0.001), preoperative eGFR <60 (9.71, P < 0.001) and elevated creatinine (5.9, P = 0.008) were risk factors for developing MA., Conclusions: Patients undergoing RN had significantly greater CRI, MA and proteinuria rates than a well-matched group undergoing NSS. In addition to RN, age > or =60 years, diabetes mellitus, hypertension and smoking were associated with progression to CRI after surgery.