Below Safety Limits, Every Unit of Glomerular Filtration Rate Counts: Assessing the Relationship Between Renal Function and Cancer-specific Mortality in Renal Cell Carcinoma

The impact of post-nephroureterectomy surgically induced chronic kidney disease on survival outcomes

OBJECTIVE

To investigate the prevalence, predictors and impact of surgically induced chronic kidney disease (CKD-S) on survival outcomes in patients with upper tract urothelial carcinoma (UTUC) following radical nephroureterectomy (RNU).

METHODS

Utilising the ROBUUST 2.0 registry, a multicentre retrospective analysis was conducted in patients with UTUC undergoing RNU between 2006 and 2022 who did not have baseline chronic kidney disease (CKD) stages 3-5. We calculated the prevalence of postoperative CKD-S3a (estimated glomerular filtration rate [eGFR] 59-45 mL/min/1.73 m2) and CKD-S3b (eGFR <45 mL/min/1.73 m2) as measured by the Chronic Kidney Disease Epidemiology Collaboration 2021 equation. The analytical cohort was stratified by postoperative CKD stage [no CKD-S [eGFR ≥60 mL/min/1.73 m2]; CKD-S3a [eGFR 59-45 mL/min/1.73 m2] and CKD-S3b [eGFR <45 mL/min/1.73 m2]). The primary outcome was all-cause mortality (ACM). Predictors for development of CKD-S3a/3b and ACM/cancer-specific mortality (CSM) were analysed using logistic and Cox regression, respectively. Kaplan-Meier analysis was used to analyse overall survival (OS) and cancer-specific survival (CSS) among postoperative CKD groups.

RESULTS

We analysed 1862 patients; 34.7% (646) and 39.6% (738), respectively, developed CKD-S3a and CKD-S3b. Predictors of CKD-S3b included increasing age (odds ratio [OR] 1.03, P = 0.029), decreasing preoperative eGFR (OR 1.06, P < 0.001) and receipt of neoadjuvant (OR 2.07, P = 0.006) and adjuvant chemotherapy (OR 1.41, P = 0.012). Worsened ACM was associated with CKD-S3b (hazard ratio 1.42, P = 0.032), but not CKD-S3a (P = 0.766). Development of CKD-S3a (P = 0.812) and CKD-S3b (P = 0.316) were not associated with CSM. The 5-year OS rate was significantly worse in CKD-S3b (no-CKD 71%, CKD-S3a 70%, CKD-S3b 59%; P = 0.017). No differences between CKD-S groups were noted for 5-year CSS (no-CKD 78%, CKD-S3a 77%, CKD-S3b 82%; P = 0.44).

CONCLUSIONS

A significant proportion of UTUC patients undergoing RNU developed CKD-S. Development of CKD-S3b was associated with worse ACM. Increasing age, preoperative eGFR, and chemotherapy were associated with developing CKD-S3b. Our findings call for further exploration and refinement of nephron-preserving surgical strategies and non-nephrotoxic systemic therapy to improve survival outcomes in UTUC.

Three-Dimensional Virtual Model for Robot-Assisted Partial Nephrectomy (RAPN): Development of Study Protocol for Evaluation of the Learning Curve to Optimize the Precision and Accuracy of the 3D Imaging

3D models have been introduced as tools to improve surgeon's precision during Robotic-Assisted Partial Nephrectomy (RAPN). They showed to provide accurate anatomical details, improve operative time and patient safety by reducing complications. Over the last years, several useful models have been developed and proposed. However, literature is still scant regarding if and how the experience of the operator, and the learning curve, may impact the accuracy and precision of the model. In this light, the aim of the study is to evaluate the accuracy, the interpersonal variability of the precision and the learning curve for the segmentation of RAPN 3D preoperative models starting from CT images. This study will identify the influence of operator experience and learning curves on the accuracy of 3D preoperative models in RAPN, optimizing workflows for broader clinical adoption.

Using three-dimensional virtual imaging of renal masses to improve prediction of robotic-assisted partial nephrectomy Tetrafecta with SPARE score

OBJECTIVE

To improve the predictability of outcomes in robotic-assisted partial nephrectomy, we utilized three-dimensional virtual imaging for SPARE nephrometry scoring. We compared this method with a conventional two-dimensional scoring system to determine whether 3D virtual images offer enhanced predictive accuracy for Tetrafecta outcomes.

METHODS

We retrospectively collected basic information, demographic data, and perioperative indices from patients who underwent robot-assisted partial nephrectomy for renal masses at the Department of Urology, First Affiliated Hospital of Xi'an Jiaotong University. A three-dimensional visualization system (IPS system, Yorktal) was employed to reconstruct the patients' imaging data using AI-based automatic segmentation, resulting in a three-dimensional visualization model (3DVM). This model was then imported into the virtual surgical planning software (Touch Viewer System, Yorktal) for automatic measurement of the SPARE score. Tetrafecta was defined as a warm ischemic time (WIT) of less than 25 min, negative surgical margins, absence of major perioperative complications, and no decline in postoperative renal function. The receiver operating characteristic (ROC) curve was utilized to evaluate the sensitivity and specificity of the SPARE score.

RESULTS

A total of 141 patients were included in this study, with a mean age of 55.6 ± 11.14 years and a mean tumor size of 3.5 ± 1.2 cm. All variables, except for estimated blood loss (EBL) (Coefficient = 0.056, 0.035; P = 0.514, 0.685), showed significant correlation with the SPARE score when comparing CT and 3D virtual models (Tetrafecta: Coefficient = 0.408, 0.56; P < 0.001, < 0.001; WIT: Coefficient = 0.340, 0.237; P < 0.001, 0.007; ΔeGFR: Coefficient = 0.212, 0.257; P = 0.012, 0.002). The area under the curve (AUC) values from the ROC curves indicated that the 3D virtual model group had significantly better performance than the 2D image group for the SPARE score. However, there was no significant difference in the ROC curves for the SPARE complexity category between the two imaging modalities (AUC for SPARE category with 3DVM = 0.658 vs. AUC for SPARE category with CT = 0.643, P = 0.59; AUC for SPARE score with 3DVM = 0.854 vs. AUC for SPARE score with CT = 0.755, P < 0.001).

CONCLUSIONS

The SPARE score combined with 3DVM has a more accurate predictive ability for Tetrafecta of RAPN compared to the traditional 2D SPARE score.

Risk factors of renal function deterioration after radical nephroureterectomy for upper tract urothelial carcinoma

Background and objectives

To investigate the risk factors of renal function deterioration after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).

Methods

A total of 153 patients with UTUC who underwent radical surgery at a high-volume center in China from January 2015 to December 2019 were included in this study. The renal function of all patients was evaluated during follow-up. Besides, these patients were grouped according to postoperative renal function. The risk factors of renal function deterioration included age, sex, body mass index (BMI), T stage, tumor location and size, lymph node invasion, lymph node dissection (LND), surgical margin, tumor histology, lymphovascular invasion (LVI), hypertension, diabetes, hematuria, blood transfusion, hydronephrosis on the affected side, urine specific gravity, creatinine, uric acid, and preoperative glomerular filtration rate (GFR) on the healthy and affected sides. The correlation between risk factors and inclusion indexes was analyzed using univariate and multivariate analyses.

Results

A total of 153 patients were enrolled in this study, and the follow-up continued for 14 (11, 24) months. Acute kidney injury (AKI) was diagnosed in 65 patients in the short-term follow-up after RNU, and renal function deterioration was diagnosed in 52 patients in the long-term follow-up after RNU. The univariate analysis of 65 patients with short-term AKI revealed that there were statistically significant differences in preoperative hydronephrosis, hypertension, urinary protein, tumor size, preoperative Hb, preoperative creatinine, blood transfusion, and preoperative GFR of the healthy kidney. The multivariate Logistic regression analysis results showed that preoperative creatinine, GFR of the healthy kidney, and blood transfusion were independent risk factors for AKI. Moreover, The multivariate Logistic regression analysis of 52 patients with long-term renal insufficiency after surgery indicated that there were statistically significant differences in preoperative hydronephrosis, tumor size, preoperative GFR of the healthy kidney, and postoperative AKI.

Conclusion

For patients with UTUC, the preoperative creatinine level is high, blood transfusion was given during or after procedure and the GFR of the healthy kidney is low, it is easy to have AKI in the short term after operation. In addition, there was no hydronephrosis before operation, the tumor size was small, the GFR of the healthy kidney was low before operation, AKI occurred after operation, the renal function was easy to deteriorate for a long time after operation. The above risk factors may aggravate renal function deterioration of these patients after surgery, resulting in the loss of the opportunity to continue treatment.

Effects of perirenal fat thickness on postoperative renal dysfunction in patients who underwent robot-assisted partial nephrectomy for renal tumours

BACKGROUND

Despite partial nephrectomy (PN) renal function preservation benefits, postoperative renal dysfunction may occur. Perirenal fat thickness (PFT) is associated with renal dysfunction such as diabetes; however, its role in renal tumour surgery is unclear. This study investigates the role of PFT in renal function after robot-assisted partial nephrectomy (RAPN).

METHODS

Pre-operative factors for postoperative renal dysfunction were analysed in 156 patients undergoing RAPN with ≥1-year follow-up. PFT measured using computed tomography categorised patients with PFT >21.0 mm (median) as high-PFT.

RESULTS

Tumour size, total R.E.N.A.L. nephrometry score and its N component, renal calyx opening, achievement of trifecta, and PFT were risk factors for renal dysfunction 1 year postoperatively. Age ≥75 years (p = 0.024), total RNS ≥7 (p = 0.036), and PFT >21.0 mm (p = 0.002) significantly correlated with postoperative renal dysfunction.

CONCLUSIONS

CT-measured PFT is a valuable predictor of postoperative renal dysfunction.

Comparing the oncologic outcomes of local tumor destruction vs. local tumor excision vs. partial nephrectomy in T1a solid renal masses: a population-based cohort study from the SEER database

BACKGROUND

There are few large-scale analyses comparing local tumor destruction (LTD) or local tumor enucleation/excision (LTE) relative to partial nephrectomy (PN) for patients with T1a renal masses in terms of cancer-specific survival (CSS) and overall survival (OS). The authors aimed to compare CSS and OS after LTD versus LTE versus PN.

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results (SEER) database (2000-2019), the authors identified patients with clinical T1a renal masses and histologically confirmed kidney cancer treated with LTD, LTE, or PN. After 1:1 ratio propensity score matching (PSM), comparisons between the groups were conducted. Kaplan-Meier analysis and log-rank tests were used to compare survival in the matched population.

RESULTS

In the overall cohort of 3717 LTD patients versus 1993 LTE patients versus 26 935 PN patients, 77.3% of LTD-treated patients and 74.4% of LTE-treated patients were over 60 years old, while only 50.3% of PN-treated patients were over 60 years old. PN was more strongly associated with CSS [hazard ratio ((HR)=1.276, P <0.001) and OS (HR=1.112, P <0.001)] than was LTD, while PN was less strongly associated with CSS (HR=1.040, P =0.230) and OS (HR=0.888, P =0.002) than was LTE, not only in the PSM cohort but also in the subgroups of patients with a tumor size ≤3 cm and patients with a tumor size of 3.1-4 cm.

CONCLUSIONS

In clinical T1a solid renal mass patients, LTD was associated with lower CSS and OS than LTE and PN, while LTE demonstrated noninferior CSS and superior OS to PN regardless of tumor size.

Impact of chronic kidney disease stages on surgical and functional outcomes in robot-assisted partial nephrectomy for localized renal tumors

The influence of chronic kidney disease stage on robot-assisted partial nephrectomy outcomes remains underexplored. This study aimed to assess the impact of chronic kidney disease stage on functional and surgical outcomes of robot-assisted partial nephrectomy and identify preoperative predictors of significant postoperative 1-year renal-function loss (RFL). Clinical data of 408 patients who underwent robot-assisted partial nephrectomy at Yokohama City University Hospital between 2016 and 2023 were retrospectively reviewed. The da Vinci Surgical System was applied in all patients, and outcomes assessed included surgical parameters, postoperative estimated glomerular filtration rate, trifecta and pentafecta achievements, and complications. Significant RFL was defined as estimated glomerular filtration rate reduction ≥ 25% from baseline. Higher chronic kidney disease stages correlated with older age, hypertension, diabetes, and solitary kidneys. Postoperative estimated glomerular filtration rate decline was most pronounced in patients with chronic kidney disease stages 4-5. Although the chronic kidney disease stage did not significantly affect most surgical parameters, pentafecta achievement was higher in patients with chronic kidney disease stage 3 than in those with stages 4-5. Two patients required hemodialysis after robot-assisted partial nephrectomy. Multivariable logistic regression analysis showed that preoperative hemoglobin level and maximum tumor diameter were significant predictive factors for significant RFL. In conclusion, preoperative CKD stage did not influence on surgical outcome except for pentafecta achievement. RAPN may be feasible for patients with CKD stages 4-5 because of no rapid progression to hemodialysis induction and no procedure-related mortality. Preoperative hemoglobin levels and tumor diameter emerged as predictors of significant RFL.

Efficacy and late kidney effects of nephron-sparing surgery in the management of unilateral Wilms tumor: a systematic review and meta-analysis

To evaluate the efficiency and long-term renal function of nephron sparing surgery (NSS) in unilateral WT patients compared with radical nephrectomy (RN). The review was performed following Cochrane Handbook guidelines and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched five databases (Pubmed, Embase, Scopus, Web of Science and Cochrane) for studies reporting the efficiency and late renal function of NSS and/or RN on February 10, 2023. Comparative studies were evaluated by Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) and RoB 2.0. Assessed outcomes included survival rate, relapse rate, eGFR, renal dysfunction and hypertension. 26 studies involving 10322 unilateral WT cases underwent RN and 657 unilateral WT cases underwent NSS were enrolled. Overall effect estimates demonstrated that NSS significantly increased eGFR at follow-up (SMD, 0.38; 95% CI 0.05-0.72; p = 0.025) compared to that at diagnosis, and RN did not significantly decrease eGFR at follow-up (SMD, - 0.33; 95% CI - 0.77-0.11; p = 0.142) compared to that at diagnosis. Moreover, no significant difference was found in outcomes of survivability (OR, 1.38; 95% CI 0.82-2.32; p = 0.226), recurrence (OR, 0.62; 95% CI 0.34-1.12; p = 0.114), eGFR at follow-up (SMD, 0.16; 95% CI - 0.36-0.69; p = 0.538), renal dysfunction (OR, 0.36; 95% CI 0.07-1.73; p = 0.200) and hypertension (OR, 0.17; 95% CI 0.03-1.10; p = 0.063). Current evidence suggests that NSS is safe and effective for unilateral WT patients, because it causes better renal function and similar oncological outcomes compared with RN. Future efforts to conduct more high-quality studies and explore sources of heterogeneity is recommended.

Predicting estimated glomerular filtration rate after partial and radical nephrectomy based on split renal function measured by radionuclide: a large-scale retrospective study

PURPOSE

The purpose of this study was to develop predictive models for postoperative estimated glomerular filtration rate (eGFR) based on the split glomerular filtration rate measured by radionuclide (rGFR), as choosing radical nephrectomy (RN) or partial nephrectomy (PN) for complex renal masses requires accurate prediction of postoperative eGFR.

METHODS

Patients who underwent RN or PN for a single renal mass at Xijing Hospital between 2008 and 2022 were retrospectively included. Preoperative split rGFR was evaluated using technetium-99 m-diethylenetriaminepentaacetic acid (Tc-99 m DTPA) renal dynamic imaging, and the postoperative short-term (< 7 days) and long-term (3 months to 5 years) eGFRs were assessed. Linear mixed-effect models were used to predict eGFRs, with marginal R2 reflecting predictive ability.

RESULTS

After excluding patients with missing follow-up eGFRs, the data of 2251 (RN: 1286, PN: 965) and 2447 (RN: 1417, PN: 1030) patients were respectively included in the long-term and short-term models. Two models were established to predict long-term eGFRs after RN (marginal R2 = 0.554) and PN (marginal R2 = 0.630), respectively. Two other models were established to predict short-term eGFRs after RN (marginal R2 = 0.692) and PN (marginal R2 = 0.656), respectively. In terms of long-term eGFRs, laparoscopic and robotic surgery were superior to open surgery in both PN and RN.

CONCLUSIONS

We developed novel tools for predicting short-term and long-term eGFRs after RN and PN based on split rGFR that can help in preoperative decision-making.

Minimally Invasive Radical Nephroureterectomy: 5-Year Update of Techniques and Outcomes

The gold standard treatment for non-metastatic upper tract urothelial cancer (UTUC) is represented by radical nephroureterectomy (RNU). The choice of surgical technique in performing UTUC surgery continues to depend on several factors, including the location and extent of the tumor, the patient's overall health, and very importantly, the surgeon's skill, experience, and preference. Although open and laparoscopic approaches are well-established treatments, evidence regarding robot-assisted radical nephroureterectomy (RANU) is growing. Aim of our study was to perform a critical review on the evidence of the last 5 years regarding surgical techniques and outcomes of minimally invasive RNU, mostly focusing on RANU. Reported oncological and function outcomes suggest that minimally invasive RNU is safe and effective, showing similar survival rates compared to the open approach.

Partial versus radical nephrectomy for the treatment of pT3aN0M0 renal cell carcinoma: A propensity score analysis

BACKGROUND

The survival benefit of partial nephrectomy (PN) in pT3a RCC patients is controversial. Here we aimed to explore the potential benefit of PN for pT3aN0M0 renal cell carcinoma (RCC).

MATERIAL AND METHODS

Data of patients with pT3aN0M0 RCC who were diagnosed between 2010 and 2012 in the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) database were retrospectively collected. Overall survival (OS) and cancer specific survival (CSS) were compared using a Cox proportional hazards model between PN and radical nephrectomy (RN) in pT3aN0M0 RCC. Propensity score (-adjusted, -stratified, -weighted, and -matched) analyses were performed to control for imbalances in individual risk factors.

RESULTS

A total of 1277 patients with pT3aN0M0 RCC were identified, of whom 200 patients were treated with PN and 1077 patients were RN. PN showed favorable OS and CSS in 0-4 cm pT3aN0M0 RCC (P < 0.05), and similar OS and CSS in 4-7 cm pT3aN0M0 RCC, compared with RN using un-adjusted analyses. The Propensity score analyses further demonstrated the survival benefit of PN compared with the RN in 0-4 cm pT3aN0M0 RCC (P < 0.05).

CONCLUSIONS

In this retrospective study, PN was associated with improved survival compared with RN in 0-4 cm pT3aN0M0 RCC. Moreover, survival was comparable between PN and RN in 4-7 cm pT3aN0M0 RCC. These data provided evidence that PN could be an alternative choice for T3aN0M0 RCC less than 7 cm. Particularly, patients with 0-4 cm pT3aN0M0 RCC might benefit from PN.

Zero ischemia robotic partial nephrectomy: Oncological and functional outcomes of a multicenter study

BACKGROUND

The functional and oncological outcomes of zero ischemia robotic partial nephrectomy (RPN) procedures were evaluated.

METHODS

A total of 56 patients underwent zero ischemia RPN transperitoneally, and their data were collected prospectively. Radius, exo/endophytic, nearness, anterior/posterior, location (R.E.N.A.L.) nephrometry, and PADUA scores were calculated. Patient and tumor characteristics were evaluated. Intra- and perioperative (0-30 days) complications were evaluated by Clavien classification. The change in serum creatinine, and estimated glomerular filtration rates (eGFR) were evaluated during preoperative, immediate postoperative periods, and at postoperative 6th months.

RESULTS

The mean age of the patients was 52.2 ± 8.1 (27-75) years. R.E.N.A.L. nephrometry and PADUA scores were 6.1 ± 1.3 and 7.3 ± 1.0, respectively. The duration of surgery was 108.4 ± 18.2 min and estimated blood loss was 166.2 ± 124.7 mL. There were no intraoperative complications in any of the patients. Clavien Grade 1 and 3 complications were seen in 2 patients in the perioperative period. In the perioperative period (1-30 days), one patient required blood transfusion and angiographic intervention due to postoperative bleeding (Clavien Grade 3), and one patient required hospitalisation due to prolonged subileus (Clavien Grade 1) that resolved conservatively. The radiological and pathological tumor sizes were 3.1 ± 1.1 cm and 2.8 ± 1.4 cm, respectively. The surgical margins were positive in two patients with tumour sizes of 1.5 and 4 cm. Neither local recurrence nor distant metastasis was detected, during 33.6 ± 12.3 (3-76) months. There were no statistically significant differences between preoperative eGFR and serum creatinine levels, compared with those of immediate postoperative and postoperative 6th month periods.

DISCUSSION

Zero ischemia RPN is a safe and applicable method with acceptable oncological and functional outcomes in small renal tumors and even in selected larger renal tumors.

A three-dimensional renal tumor anatomy and intrarenal relationship nephrometry (ADDD) for robot-assisted partial nephrectomy : 3D-CT based nephrometry for RAPN

OBJECTIVE

To develop a 3D scoring system of tumor anatomy and intrarenal relationship for assessing surgical complexity and outcomes of robot-assisted partial nephrectomy (RAPN).

METHODS

We prospectively enrolled patients with a renal tumor who had a 3D model and underwent RAPN between Mar 2019 and Mar 2022. The ADDD nephrometry consisted of the contact surface area between tumor and parenchyma (A), the depth of tumor invasion into the renal parenchyma (D1), the distance from tumor to the main intrarenal artery (D2), and to the collecting system (D3). The primary outcomes included perioperative complication rate and trifecta outcome (WIT ≤ 25 min, negative surgical margins, and no major complications).

RESULTS

We enrolled a total of 301 patients. The mean tumor size was 2.93 ± 1.44 cm. There were 104 (34.6%) patients, 119 (39.5%) patients, and 78 (25.9%) patients in the low-, intermediate-, and high-risk groups, respectively. Each point increase in the ADDD score increased the risk of complications [hazard ratio (HR) 1.501]. A lower grade indicated a lower risk of failed trifecta (HR low group 15.103, intermediate group 9.258) and renal function damage (HR low risk 8.320, intermediate risk 3.165) compared to the high-risk group. The AUC of ADDD score and grade were 0.738 and 0.645 for predicting major complications, 0.766 and 0.714 for predicting trifecta outcome, and 0.746 and 0.730 for predicting postoperative renal function reservation.

CONCLUSION

The 3D-ADDD scoring system shows the tumor anatomy and its intraparenchymal relationships and has better efficacy in predicting surgical outcomes of RAPN.

New-onset Chronic Kidney Disease After Surgery for Localised Renal Masses in Patients with Two Kidneys and Preserved Renal Function: A Contemporary Multicentre Study

Background

There is a lack of evidence on acute kidney injury (AKI) and new-onset chronic kidney disease (CKD) after surgery for localised renal masses (LRMs) in patients with two kidneys and preserved baseline renal function.

Objective

To evaluate the prevalence and risk of AKI and new-onset clinically significant CKD (csCKD) in patients with a single renal mass and preserved renal function after being treated with partial (PN) or radical (RN) nephrectomy.

Design setting and participants

We queried our prospectively maintained databases to identify patients with a preoperative estimated glomerular filtration rate (eGFR) of ≥60 ml/min/1.73 m² and a normal contralateral kidney who underwent PN or RN for a single LRM (cT1-T2N0M0) between January 2015 and December 2021 at four high-volume academic institutions.

Intervention

PN or RN.

Outcome measurements and statistical analysis

The outcomes of this study were AKI at hospital discharge and the risk of new-onset csCKD, defined as eGFR <45 ml/min/1.73 m², during the follow-up. Kaplan-Meier curves were used to examine csCKD-free survival according to tumour complexity. A Multivariable logistic regression analysis assessed the predictors of AKI, while a multivariable Cox regression analysis assessed the predictors of csCKD. Sensitivity analyses were performed in patients who underwent PN.

Results and limitations

Overall, 2469/3076 (80%) patients met the inclusion criteria. At hospital discharge, 371/2469 (15%) developed AKI (8.7% vs 14% vs 31% in patients with low- vs intermediate- vs high-complexity tumours, p < 0.001). At the multivariable analysis, body mass index, history of hypertension, tumour complexity, and RN significantly predicted the occurrence of AKI. Among 1389 (56%) patients with complete follow-up data, 80 events of csCKD were recorded. The estimated csCKD-free survival rates were 97%, 93% and 86% at 12, 36, and 60 mo, respectively, with significant differences between patients with high- versus low-complexity and high- versus intermediate-complexity tumours (p = 0.014 and p = 0.038, respectively). At the Cox regression analysis, age-adjusted Charlson Comorbidity Index, preoperative eGFR, tumour complexity, and RN significantly predicted the risk of csCKD during the follow-up. The results were similar in the PN cohort. The main limitation of the study was the lack of data on eGFR trajectories within the 1st year after surgery and on long-term functional outcomes.

Conclusions

The risk of AKI and de novo csCKD in elective patients with an LRM and preserved baseline renal function is not clinically negligible, especially in those with higher-complexity tumours. While baseline nonmodifiable patient/tumour-related characteristics modulate this risk, PN should be prioritised over RN to maximise nephron preservation if oncological outcomes are not jeopardised.

Patient summary

In this study, we evaluated how many patients with a localised renal mass and two functioning kidneys, who were candidates for surgery at four referral European centres, experienced acute kidney injury at hospital discharge and significant renal functional impairment during the follow-up. We found that the risk of acute kidney injury and clinically significant chronic kidney disease in this patient population is not negligible, and was associated with specific baseline patient comorbidities, preoperative renal function, tumour anatomical complexity, and surgery-related factors, in particular the performance of radical nephrectomy.

The role of warm ischemia time on functional outcomes after robotic partial nephrectomy: a radionuclide renal scan study from the clock randomized trial

PURPOSE

To evaluate the relationship between warm ischemia time (WIT) duration and renal function after robot-assisted partial nephrectomy (RAPN).

METHODS

The CLOCK trial is a phase 3 randomized controlled trial comparing on- vs off-clamp RAPN. All patients underwent pre- and postoperative renal scintigraphy. Six-month absolute variation of eGFR (AV-GFR), rate of relative variation in eGFR over 25% (RV-GFR > 25), absolute variation of split renal function (SRF) at scintigraphy (AV-SRF). The relationships WIT/outcomes were assessed by correlation graphs and then modeled by uni- and multivariable regression.

RESULTS

324 patients were included (206 on-clamp, 118 off-clamp RAPN). Correlation graphs showed a threshold on WIT equal to 10 min. The differences in outcome measures between cases with WIT < vs ≥ 10 min were: AV-GFR - 3.7 vs - 7.5 ml/min (p < 0.001); AV-SRF - 1% vs - 3.6% (p < 0.001); RV-GFR > 25 9.3% vs 17.8% (p = 0.008). Multivariable models found that AV-GFR was related to WIT ≥ 10 min (regression coefficient [RC] - 0.52, p = 0.019), age (RC - 0.35, p = 0.001) and baseline eGFR (RC - 0.30, p < 0.001); RV-GFR > 25 to WIT ≥ 10 min (odds ratio [OR] 1.11, p = 0.007) and acute kidney injury defined as > 50% increase in serum creatinine (OR 19.7, p = 0.009); AV-SRF to WIT ≥ 10 min (RC - 0.30, p = 0.018), baseline SRF (RC - 0.76, p < 0.001) and RENAL score (RC - 0.60. p = 0.028). The main limitation was that the CLOCK trial was designed on a different endpoint and therefore the present analysis could be underpowered.

CONCLUSIONS

Up to 10 min WIT had no consequences on functional outcomes. Above the 10-min threshold, a statistically significant, but clinically negligible impact was found.

Robotic Partial Nephrectomy for Bilateral Renal Masses

PURPOSE OF REVIEW

There are very few data on patients undergoing robot-assisted partial nephrectomy (RAPN) for bilateral renal masses. The aim of this review is to update the literature and discuss the controversial points on this topic.

RECENT FINDINGS

Nine papers have been published regarding RAPN for bilateral renal masses. In particular, five papers were case reports while the remaining four reported patient series. Concerning the outcomes, all these papers highlighted the safety, feasibility, and efficacy of bilateral RAPN for bilateral renal masses. The literature confirmed RAPN as an optimal procedure for the treatment of bilateral renal masses. However, these outcomes mainly derived from selected group of patients who underwent complex surgical procedures by expert robotic surgeons at high volume centers and cannot be generalizable to all categories of patients or centers. The simultaneous bilateral approach resulted feasible showing some advantages and without higher complications than a staged procedure in particular when clampless or selective clamping techniques were performed.

Novel Biomarkers for Early Detection of Acute Kidney Injury and Prediction of Long-Term Kidney Function Decline after Partial Nephrectomy

Background: Identifying acute kidney injury (AKI) within few hours of onset is certainly helpful. However, early prediction of a long-term eGFR decline may be an even more important goal. Our aim was to identify and compare serum [creatinine, kineticGFR, cystatin C, neutrophil gelatinase–associated lipocalin (NGAL)] and urinary (NephroCheck, NGAL, proteinuria, albuminuria, acantocytes at urinary sediment) predictors of AKI that might efficiently predict long-term GFR decline after robotic Nephron-Spearing Surgery (rNSS). Methods: Monocentric prospective observational study. Patients scheduled for rNSS for suspected localized Renal Cell Carcinoma from May 2017 to October 2017 were enrolled. Samples were collected preoperatively and postoperatively (timepoints: 4 h, 10 h, 24 h, 48 h), while kidney function was re-assessed up to 24 months. Results: 38 patients were included; 16 (42%) developed clinical AKI. The eGFR decline at 24 months was more pronounced after postoperative AKI (−20.75 vs. −7.20, p < 0.0001). KineticGFR at 4 h (p = 0.008) and NephroCheck at 10 h (p = 0.001) were, at multivariable linear regression analysis, efficient predictors of post-operative AKI and long-term eGFR decline if compared to creatinine (R2 0.33 vs. 0.04). Conclusions: NephroCheck and kineticGFR have emerged as promising noninvasive, accurate, and early biomarkers of postoperative AKI and long-term GFR decline after rNSS. Combining NephroCheck and kineticGFR in clinical practice would allow to identify high risk of postoperative AKI and long-term GFR decline as early as 10 h after surgery.

Estimating Postoperative Renal Function After Surgery for Nonmetastatic Renal Masses: A Systematic Review of Available Prediction Models

CONTEXT

A variety of models predicting postoperative renal function following surgery for nonmetastatic renal tumors have been reported, but their validity and clinical usefulness have not been formally assessed.

OBJECTIVE

To summarize prediction models available for estimation of mid- to long-term (>3 mo) postoperative renal function after partial nephrectomy (PN) or radical nephrectomy (RN) for nonmetastatic renal masses that include only preoperative or modifiable intraoperative variables.

EVIDENCE ACQUISITION

A systematic review of the English-language literature was conducted using the MEDLINE, Embase, and Web of Science databases from January 2000 to March 2022 according to the PRISMA guidelines (PROSPERO ID: CRD42022303492). Risk of bias was assessed according to the Prediction Model Study Risk of Bias Assessment Tool.

EVIDENCE SYNTHESIS

Overall, 21 prediction models from 18 studies were included (nine for PN only; eight for RN only; four for PN or RN). Most studies relied on retrospective patient cohorts and had a high risk of bias and high concern regarding the overall applicability of the proposed model. Patient-, kidney-, surgery-, tumor-, and provider-related factors were included among the predictors in 95%, 86%, 100%, 61%, and 0% of the models, respectively. All but one model included both patient age and preoperative renal function, while only a few took into account patient gender, race, comorbidities, tumor size/complexity, and surgical approach. There was significant heterogeneity in both the model building strategy and the performance metrics reported. Five studies reported external validation of six models, while three assessed their clinical usefulness using decision curve analysis.

CONCLUSIONS

Several models are available for predicting postoperative renal function after kidney cancer surgery. Most of these are not ready for routine clinical practice, while a few have been externally validated and might be of value for patients and clinicians.

PATIENT SUMMARY

We reviewed the tools available for predicting kidney function after partial or total surgical removal of a kidney for nonmetastatic cancer. Most of the models include patient and kidney characteristics such as age, comorbidities, and preoperative kidney function, and a few also include tumor characteristics and intraoperative variables. Some models have been validated by additional research groups and appear promising for improving counseling for patients with nonmetastatic cancer who are candidates for surgery.

Cancer-specific Mortality in T1a Renal Cell Carcinoma Treated with Local Tumor Destruction Versus Partial Nephrectomy

BACKGROUND

Large-scale analyses addressing cancer-specific mortality (CSM) in T1a renal cell carcinoma (RCC) patients treated with local tumor destruction (LTD), relative to partial nephrectomy (PN), are scarce.

OBJECTIVE

To compare CSM after LTD versus PN.

DESIGN, SETTING, AND PARTICIPANTS

Within the Surveillance, Epidemiology, and End Results (SEER) database (2004-2018), we identified patients with clinical T1a stage RCC treated with LTD or PN.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

After 1:1 ratio propensity score matching (PSM) between patients treated with LTD versus PN, competing risks regression (CRR) models addressed CSM, after adjustment for other-cause mortality (OCM) and other covariates (age, tumor size, tumor grade, and histological subtype).

RESULTS AND LIMITATIONS

Relative to the 35 984 PN patients, 5936 LTD patients were older and more frequently harbored unknown RCC histological subtype or unknown grade. After 1:1 PSM that resulted in 5352 LTD versus 5352 PN patients, the 10-yr CSM rate was 8.7% versus 5.5%. In multivariable CRR models, LTD was associated with higher CSM, relative to PN (hazard ratio [HR]: 1.58, p < 0.001). Subgroup analyses revealed invariably higher CSM after LTD versus PN in patients with tumor size ≤3 cm (10-yr CSM 7.2% vs 5.3%, multivariable HR: 1.47, p < 0.001) and in patients with tumor size 3.1-4 cm (10-yr CSM 11.4% vs 6.1%, multivariable HR: 1.72, p < 0.001). Lack of information regarding earlier cancer controls, retreatment, tumor location within the kidney, and type of surgery represented limitations.

CONCLUSIONS

In T1a RCC patients, LTD is invariably associated with higher CSM relative to PN, even after adjustment for OCM and all available patient and tumor characteristics, and regardless of tumor size considerations. However, the magnitude of CSM disadvantage was more pronounced in LTD patients with tumor size 3.1-4 cm than in those with tumor size ≤3 cm.

PATIENT SUMMARY

In patients with small renal masses, we observed higher cancer-specific death rates for local tumor destruction (LTD) than for partial nephrectomy. The LTD disadvantage was more pronounced for patients with tumor size 3.1-4 cm, but was also present in those with tumor size ≤3 cm.

Artificial intelligence-based prediction of overall survival in metastatic renal cell carcinoma

Background and objectives

Investigations of the prognosis are vital for better patient management and decision-making in patients with advanced metastatic renal cell carcinoma (mRCC). The purpose of this study is to evaluate the capacity of emerging Artificial Intelligence (AI) technologies to predict three- and five-year overall survival (OS) for mRCC patients starting their first-line of systemic treatment.

Patients and methods

The retrospective study included 322 Italian patients with mRCC who underwent systemic treatment between 2004 and 2019. Statistical analysis included the univariate and multivariate Cox proportional-hazard model and the Kaplan-Meier analysis for the prognostic factors' investigation. The patients were split into a training cohort to establish the predictive models and a hold-out cohort to validate the results. The models were evaluated by the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. We assessed the clinical benefit of the models using decision curve analysis (DCA). Then, the proposed AI models were compared with well-known pre-existing prognostic systems.

Results

The median age of patients in the study was 56.7 years at RCC diagnosis and 78% of participants were male. The median survival time from the start of systemic treatment was 29.2 months; 95% of the patients died during the follow-up that finished by the end of 2019. The proposed predictive model, which was constructed as an ensemble of three individual predictive models, outperformed all well-known prognostic models to which it was compared. It also demonstrated better usability in supporting clinical decisions for 3- and 5-year OS. The model achieved (0.786 and 0.771) AUC and (0.675 and 0.558) specificity at sensitivity 0.90 for 3 and 5 years, respectively. We also applied explainability methods to identify the important clinical features that were found to be partially matched with the prognostic factors identified in the Kaplan-Meier and Cox analyses.

Conclusions

Our AI models provide best predictive accuracy and clinical net benefits over well-known prognostic models. As a result, they can potentially be used in clinical practice for providing better management for mRCC patients starting their first-line of systemic treatment. Larger studies would be needed to validate the developed model.

Age-Related Differences in Oncological Outcomes in Renal Cell Carcinoma: Impact of Functional Conservation as Measured by Postoperative eGFR

INTRODUCTION

We sought to determine whether loss of renal function increases risk of recurrence and metastases in renal cell carcinoma (RCC), and whether this impact was age-related.

MATERIALS AND METHODS

We performed a retrospective analysis of the International Marker Consortium for Renal Cancer (INMARC) registry. Patients were separated into younger (<65 years old) and elder (≥65 years old) age groups, and rates of de novo estimated glomerular filtration rate (eGFR<45 mL/min/1.73m2 [eGFR<45]) were calculated. Multivariable analysis (MVA) was conducted for predictors of progression-free survival (PFS) and all-cause mortality (ACM). Kaplan-Meier Analysis (KMA) was conducted for PFS and overall survival (OS) in younger and elder age groups stratified by functional status.

RESULTS

We analyzed 1805 patients (1113 age<65, 692 age≥65). On MVA in patients <65, de novo eGFR<45 was independently associated with greater risk for worsened progression (HR=1.61, P=.038) and ACM (HR=1.82, P=.018). For patients ≥65, de novo eGFR<45 was not independently associated with progression (P=.736), or ACM (P=.286). Comparing patients with de novo eGFR<45 vs. eGFR ≥45, KMA demonstrated worsened 5-year PFS and OS in patients <65 (PFS: 68% vs. 86%, P<.001; OS: 73% vs. 90%, P<.001), while in patients ≥65, only 5-year OS was worsened (77% vs. 81%, P<.021).

CONCLUSION

Development of de novo eGFR<45 was associated with more profound impact on patients <65 compared to patients ≥65, being an independent risk factor for PFS and ACM. The mechanisms of this phenomenon are unclear but underscore desirability for nephron preservation when safe and feasible in younger patients.

Imaging Features of Renal Masses to Select Optimal Candidates for Tumor Enucleation Partial Nephrectomy

PURPOSE OF REVIEW

The goal of this paper was to critically evaluate preoperative findings that optimally select candidates for renal tumor enucleation partial nephrectomy.

RECENT FINDINGS

Tumor enucleation has been widely accepted as a management option for patients with chronic kidney disease, hereditary renal cell carcinoma, or multifocal disease. Recent evidence suggests safety and efficacy in the management of routine small renal masses. With recent advances in imaging, the literature for ruling out aggressive renal cell carcinoma and selection for tumor enucleation is robust. As the incidence of renal cell carcinoma rises, partial nephrectomy continues to be the mainstay of treatment for localized renal cell carcinoma. Tumor enucleation maximizes preservation of renal parenchyma without hindering oncologic outcomes. It is important to recognize key tumor radiologic findings which urologists may use to optimize patient selection for tumor enucleation.

Purely Off-Clamp Partial Nephrectomy: Robotic Approach Better than Open Using a Pentafecta Outcome with Propensity Score Matching

Partial nephrectomy (PN) is the gold standard treatment for localized renal masses. Robot-assisted PN (RAPN) has overcome laparoscopy’s technical limitations, greatly expanding the indications of minimally invasive PN, which is dominated by renal artery clamping in almost all published series. We compared off-clamp RAPN (OFFC-RAPN) with the open approach (OFFC-OPN) using propensity score (PS) matching. A favourable pentafecta outcome was defined as a combination of no positive surgical margins (PSM), no complications of Clavien−Dindo (CD) grade ≥ 3, post-operative eGFR loss <10%, length of hospital stay (LOS) ≤ 5 days and estimated blood loss (EBL) < 200 mL. A total of 340 consecutive patients were included. The PS-matched cohort included 142 patients: 71 matched pairs well-balanced for all covariates. The OFFC-RAPN group showed significantly shorter operative time (149.8 vs. 173.9 min, p = 0.003), lower EBL (182.1 vs. 329.3 mL, p = 0.001), and shorter LOS (5.8 vs. 6.9 days, p = 0.02), with a higher proportion of patients with LOS ≤ 5 days (57.7% vs. 23.9%, p < 0.001). No significant differences were found for PSM rate (2.8% vs. 8.4%, p = 0.27), CD > 2 complication rate (4.2% vs. 2.8%, p = 1.00) and mean ± SD eGFR change (−0.06 ± 0.3 vs. −0.8 ± 0.3, p = 0.5). Pentafecta was achieved in 56.3% and 21.1% in the OFFC-RAPN and OFFC-OPN series, respectively (p < 0.0001). On multivariable analysis, surgical approach and BMI proved to be independent predictors of achieving pentafecta. After adjusting for potential treatment selection bias, OFFC-RAPN outperformed OFFC-OPN for important peri-operative outcomes, without compromising oncological and functional safety.

The multispeciality approach to the management of localised kidney cancer

Historically, kidney cancer was approached in a siloed single-speciality way, with urological surgeons managing the localised stages of the disease and medical oncologists caring for patients if metastases developed. However, improvements in the management of localised kidney cancer have occurred rapidly over the past two decades with greater understanding of the disease biology, diagnostic options, and innovations in curative treatments. These developments are favourable for patients but provide a substantially more complex landscape for patients and clinicians to navigate, with associated challenging decisions about who to treat, how, and when. As such, the skill sets needed to manage the various aspects of the disease and guide patients appropriately outstrips the capabilities of one particular specialist, and the evolution of a multispeciality approach to the management of kidney cancer is now essential. In this Review, we summarise the current best multispeciality practice for the management of localised kidney cancer and the areas in need of further research and development.

Comprehensive analysis of 7-methylguanosine and immune microenvironment characteristics in clear cell renal cell carcinomas

Clear cell renal cell carcinoma (ccRCC) is one of the most common tumors in the urinary system. ccRCC has obvious immunological characteristics, and the infiltration of immune cells is related to the prognosis of ccRCC. The effect of immune checkpoint therapy is related to the dynamic changes of the tumor immune microenvironment (TIM). The 7-methylguanosine (m7G) is an additional mRNA modification ability besides m6A, which is closely related to the TIM and affects the occurrence and development of tumors. At present, the correlations between m7G and the immune microenvironment, treatment, and prognosis of ccRCC are not clear. As far as we know, there was no study on the relationship between m7G and the immune microenvironment and survival of clear cell renal cell carcinomas. A comprehensive analysis of the correlations between them and the construction of a prognosis model are helpful to improve the treatment strategy. Two different molecular subtypes were identified in 539 ccRCC samples by describing the differences of 29 m7G-related genes. It was found that the clinical features, TIM, and prognosis of ccRCC patients were correlated with the m7G-related genes. We found that there were significant differences in the expression of PD-1, CTLA4, and PD-L1 between high- and low-risk groups. To sum up, m7G-related genes play a potential role in the TIM, treatment, and prognosis of ccRCC. Our results provide new findings for ccRCC and help to improve the immunotherapy strategies and prognosis of patients.

Laparoscopic nephron sparing surgery and radical nephrectomy in cT1 renal tumors. Comparative analysis of complications and survival

INTRODUCTION AND OBJECTIVES

Comparative analysis of postoperative complications and survival between laparoscopic partial nephrectomy (PN) and radical nephrectomy (RN) in cT1 renal cell carcinoma (RCC).

MATERIAL AND METHOD

Retrospective study of patients with two kidneys and single renal tumor cT1 treated in our center between 2005 and 2018 by laparoscopic PN or RN.

RESULTS

372 patients met the inclusion criteria for the study. RN was performed in 156 (41.9%) patients and PN in 216 (58.1%). Clavien Dindo III-V complications were observed in 10 (4,6%) PN and 6 (3,9%) RN patients (p = 0.75). The comorbidity Charlson index (CCI) was identified as an independent predictor variable of complications (p = 0.02) and surgical approach did not affect multivariate analysis. Estimated overall survival (OS) was 81.2% and 56.8% at 5 and 10 years in the RN group and 90.2% and 75.7% in the PN group, respectively (p = 0.0001). Obesity (HR 2.77, p = 0.01), CCI ≥ 3 (HR 3.69, p = 0.001) and glomerular filtration rate (GFR) <60 mL/min/1.73 m² at discharge (HR 1.87, p = 0.03) were identified as predictors of overall mortality. Nephrectomy approach showed no influence on OS. Estimated recurrence-free survival (RFS) was 86.1% at 5 and 10 years in the RN group and 93.5% and 83.6% in the PN group, respectively (p = 0.22).

CONCLUSIONS

Laparoscopic PN is not inferior to RN in terms of oncologic and surgical safety in cT1 RCC. Nephrectomy approach did not influence patient OS, however, obesity, CCI ≥ 3 and GFR <60 mL/min/1.73 m² at discharge did behave as predictors.

Evolution of renal function in patients with cT1 renal tumors after laparoscopic partial and radical nephrectomy. Predictive factors for renal function impairment

INTRODUCTION AND OBJECTIVES

To analyze the evolution of kidney function after laparoscopic partial nephrectomy (PN) and radical nephrectomy (RN) and to identify predictive factors for renal function impairment.

MATERIALS AND METHOD

Retrospective study of patients with two kidneys, glomerular filtration rate (GFR) > 60 mL/min/1.73 m² and single renal tumor cT1, treated in our center between 2005 and 2018.

RESULTS

A total of 372 patients met the inclusion criteria for the study; 156 (41.9%) were treated with RN and 216 (58.1%) with PN. There was a difference of 26.75 mL/min/1.73 m² in GFR between RN and PN at discharge. Age >60 years, postoperative complications (OR 2.97, p = 0.005) and RN (OR 10.03, p = 0.0001) were predictors of GFR <60 mL/min/1.73 m² at discharge. Only RN (OR 7.69, p = 0.0001) behaved as an independent prognostic factor for GFR <45 mL/min/1.73 m² at discharge. The median follow-up of the series was 57 (IQR 28-100) months. At the end of the follow-up period, nine (6%) patients treated with RN developed severe chronic kidney disease (CKD) and three (2%) developed end stage renal disease (ESRD). Age >70 years, diabetes mellitus (DM) (HR 2.12, p = 0.001), arterial hypertension (AHT) (HR 1.73, p = 0.01) and RN (HR 2.88, p = 0.0001) behaved as independent predictors of GFR <60 mL/min/1.73 m². The independent predictors for GFR <45 mL/min/1.73 m² were age >70 years, DM (HR 1.99 CI 95% 1.04-3.83, p = 0.04) and RN (HR 5.88 CI 95% 2.57-13.45, p = 0.0001).

CONCLUSIONS

RN is a short- and long-term risk factor for CKD although with a low probability of severe CKD or ESRD in patients with preoperative GFR >60 mL/min/1.73 m². Age, DM and AHT contribute to worsening renal function during follow-up.

Partial and Radical Nephrectomy Provides Equivalent Oncologic Outcomes in pT3a Renal Cell Carcinoma: A Population-Based Study

Purpose

To compare the cause-specific survival (CSS) and overall survival (OS) of patients with localized T3a renal cell carcinoma (RCC) after partial nephrectomy (PN) or radical nephrectomy (RN).

Methods

We obtained the demographic and clinicopathological data of 7,127 patients with localized T3a RCC and who underwent PN or RN from the Surveillance, Epidemiology, and End Results (SEER) database. These patients were divided into fat invasion cohort and venous invasion cohort for subsequent analysis. Kaplan–Meier analysis (KMA) and univariate and multivariate Cox proportional hazards regression analyses were used to evaluate the effects of PN or RN on OS and CSS. Meanwhile, 65 cases with clinical T1 (cT1) RCC upstaged to pathological T3a (pT3a) who were treated in Tongji Hospital (TJH) from 2011 to 2020 and underwent PN or RN were identified.

Results

In the study cohort, 2,085 (29.3%) patients died during the 1–172 months’ follow-up, of whom 1,155 (16.2%) died of RCC. In the two cohorts of fat invasion and venous invasion, KMA indicated that the PN group had favorable survival (p < 0.001). However, after propensity score matching (PSM), univariate and multivariate Cox regression analyses showed that the PN and RN groups had comparable CSS in the fat invasion cohort (p = 0.075) and the venous invasion cohort (p = 0.190). During 1–104 months of follow-up, 9 cases in the Tongji cohort had disease recurrence. There was no significant difference in recurrence-free survival between the RN group and the PN group (p = 0.170).

Conclusions

Our analysis showed that after balancing these factors, patients with localized pT3a RCC receiving PN or RN can achieve comparable oncologic outcomes. PN is safe for selected T3a patients.

External validation of the Palacios' equation: a simple and accurate tool to estimate the new baseline renal function after renal cancer surgery

PURPOSE

To externally validate the Palacios' equation estimating the new baseline glomerular filtration rate (NB-GFR) after partial or radical-nephrectomy (PN, RN) for Renal cancer carcinoma (RCC).

MATERIALS AND METHODS

Our research group recently published two studies that investigated the association between renal function and cancer-specific survival in RCC. The first one included 3457 patients undergone RN or PN for a cT1-2 RCC coming from five high-volume centers; the second one considered 1767 patients undergone RN or PN for a cT1-4 RCC in a single high-volume center. From such datasets, available complete patients' data were used to calculate the predicted NB-GFR through the Palacios' equation: predicted NB-GFR = 35.03 + 0.65 ∙ preoperative GFR - 18.19 ∙ (if radical nephrectomy) - 0.25 ∙ age + 2.83 ∙ (if tumor size > 7 cm) - 2.09 ∙ (if diabetes). The observed NB-GFR was calculated by the CKD-EPI equation on serum creatinine at 3-12 months after surgery. Concordance between observed and predicted NB-GFR was evaluated by Lin's concordance correlation coefficient and Bland-Altman analysis.

RESULTS

2419 patients were included (1210, cohort #1; 1219, cohort #2). The median observed NB-GFR value in cohorts #1 and #2 was 73.0 ml/min/1.73 m2 (IQR 56.1-90.1) and 64.2 ml/min/1.73 m2 (IQR 49.6-83); the median predicted NB-GFR was 71.1 ml/min/1.73 m2 (IQR 58-81.5) and 62.6 ml/min/1.73m2 (IQR 47.9-75.9). The concordance line showed a slope of 0.80 and 0.86, and an intercept at 11.02 and 5.41 ml/min/1.73 m2 in the cohort#1 and #2, respectively. The Palacio's equation moderately over-estimated and under-estimated NB-GFR, for values below and above the cut-off of 50 ml/min/1.73 m2 and 35 ml/min/1.73m2 in cohort#1 and #2. The Lin's concordance correlation coefficient was 0.79 (95% CI 0.77-0.81) and 0.83 (95% CI 0.82-0.85).

CONCLUSIONS

We confirm the predictive performances of Palacios' equation, supporting its utilization in clinical practice.

Analysis of Related Factors of Early Mortality in Patients with Severe Renal Injury Treated with Continuous Venovenous Hemodialysis

Background. To explore the related factors of early mortality in patients with severe renal injury treated with continuous venovenous hemodialysis (CVVHD), this study is of great significance to improve the treatment effect of hemodialysis. Methods. Clinical data of 83 patients with severe renal injury who underwent CVVHD treatment in Nephrology Department of our hospital (January 1, 2017, to June 30, 2019) were retrospectively analyzed. Results. Mortality was the highest in the first month of CVVHD treatment and then decreased obviously. Early mortality was particularly higher in patients aged 60 and above. Age of first hemodialysis, cardio cerebrovascular diseases, serum phosphorus, urea nitrogen, blood calcium, platelet count, lean body mass (LBM), and total cholesterol were significant risk factors for early mortality. Conclusion. The early mortality of patients with severe renal injury during CVVHD treatment was higher.

Simultaneous robotic partial nephrectomy for bilateral renal masses

PURPOSE

There is currently no consensus regarding the optimal treatment strategy for patients presenting with synchronous bilateral renal masses. The decision to perform bilateral procedures on the same intervention or in staged procedures is debated. The aim of this manuscript is to analyse the outcomes of simultaneous robot-assisted partial nephrectomy (RAPN) in a series of patients with bilateral renal masses treated at five Italian robotic institutions.

METHODS

Data from a prospectively maintained multi-institutional database on patients subjected to simultaneous RAPN between November 2011 and July 2019 were reviewed. RAPNs were performed with da Vinci Si or Xi surgical system by expert robotic surgeons. Baseline demographics and clinical features, peri- and post-operative data were collected.

RESULTS

Overall, 27 patients underwent simultaneous bilateral RAPN, and 54 RAPNs were performed without need of conversion; median operative time was 250 minutes, median estimated blood loss was 200 mL. Renal artery clamping was needed for 27 (50%) RAPNs with a median warm ischemia time of 15 minutes and no case of acute kidney injury. Complications were reported in 7 (25.9%) patients, mainly represented by Clavien 2 events (6 blood transfusions). Positive surgical margins were assessed in 2 (3.7%) of the renal cell carcinoma. At the median follow-up of 30 months, recurrence-free survival was 100%.

CONCLUSION

Our data showed that, in selected patients and expert hands, simultaneous bilateral RAPNs could be a safe and feasible procedure with promising results for the treatment of bilateral synchronous renal masses.

Changes in renal function after nephroureterectomy for upper urinary tract carcinoma: analysis of a large multicenter cohort (Radical Nephroureterectomy Outcomes (RaNeO) Research Consortium)

PURPOSE

To investigate prevalence and predictors of renal function variation in a multicenter cohort treated with radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).

METHODS

Patients from 17 tertiary centers were included. Renal function variation was evaluated at postoperative day (POD)-1, 6 and 12 months. Timepoints differences were Δ1 = POD-1 eGFR - baseline eGFR; Δ2 = 6 months eGFR - POD-1 eGFR; Δ3 = 12 months eGFR - 6 months eGFR. We defined POD-1 acute kidney injury (AKI) as an increase in serum creatinine by ≥ 0.3 mg/dl or a 1.5 1.9-fold from baseline. Additionally, a cutoff of 60 ml/min in eGFR was considered to define renal function decline at 6 and 12 months. Logistic regression (LR) and linear mixed (LM) models were used to evaluate the association between clinical factors and eGFR decline and their interaction with follow-up.

RESULTS

A total of 576 were included, of these 409(71.0%) and 403(70.0%) had an eGFR < 60 ml/min at 6 and 12 months, respectively, and 239(41.5%) developed POD-1 AKI. In multivariable LR analysis, age (Odds Ratio, OR 1.05, p < 0.001), male gender (OR 0.44, p = 0.003), POD-1 AKI (OR 2.88, p < 0.001) and preoperative eGFR < 60 ml/min (OR 7.58, p < 0.001) were predictors of renal function decline at 6 months. Age (OR 1.06, p < 0.001), coronary artery disease (OR 2.68, p = 0.007), POD-1 AKI (OR 1.83, p = 0.02), and preoperative eGFR < 60 ml/min (OR 7.80, p < 0.001) were predictors of renal function decline at 12 months. In LM models, age (p = 0.019), hydronephrosis (p < 0.001), POD-1 AKI (p < 0.001) and pT-stage (p = 0.001) influenced renal function variation (ß 9.2 ± 0.7, p < 0.001) during follow-up.

CONCLUSION

Age, preoperative eGFR and POD-1 AKI are independent predictors of 6 and 12 months renal function decline after RNU for UTUC.

Comparison of prognosis between patients undergoing radical nephrectomy versus partial nephrectomy for renal cell carcinoma ≤7 cm T3aN0/xM0: Survival benefit is biased toward partial nephrectomy

BACKGROUND

There is limited and controversial evidence on the prognosis of partial nephrectomy (PN) versus radical nephrectomy (RN) in patients with T3aN0/xM0 renal cell carcinoma (RCC) upstaged from clinical T1 RCC. In this study, we aimed to assess the prognosis difference following PN versus RN in patients with ≤7 cm T3aN0/xM0 RCC.

METHODS

From the Surveillance, Epidemiology, and End Results database, a total of 3196 patients receiving treatment of PN/RN for ≤7 cm T3aN0/xM0 RCC with only extrarenal fat extension in 2010-2017 were identified. An inverse probability of treatment weighting (IPTW)-adjusted cause-specific Cox model with hazard ratio (HR) and 95% confidence interval (CI) was used for overall survival (OS) and cancer-specific survival (CSS) analyses. Sensitivity analysis was based on the propensity score matching of PN and RN groups and from the dataset of 2010-2013.

RESULTS

A total of 872 patients underwent PN, compared with 2324 undergoing RN. After IPTW adjustment, there was no significant difference in preoperative baseline characteristics between the PN and RN cohorts. Patients who underwent RN had worse OS (HR_{IPTW-adjusted} , 1.46; 95% CI, 1.16-1.84; p = 0.001) and comparable CSS (HR_{IPTW-adjusted} , 1.03; 95% CI, 0.64-1.66; p = 0.890) than those receiving PN in all cohorts and subgroups with T3a RCC of ≤4 cm and perinephric fat extension. Further, in patients with 4-7 cm T3a RCC with perinephric-fat invasion and all sizes of T3a RCC with sinus/perisinus fat extension, PN led to comparable OS and CSS. Sensitivity analyses validated these results.

CONCLUSION

PN provides comparable CSS and OS or even better OS than RN for patients with RCC ≤7 cm T3aN0/xM0. Although our study has some limitations, our results indicated that PN might oncologically safe for clinical T1 RCC, even confirmed a pathologically T3a upstaging post-PN.

Parenchymal Volume Replacement by Renal Cell Carcinoma Prior to Intervention: Predictive Factors and Functional Implications

OBJECTIVE

To analyze predictors, extent and functional implications associated with renal parenchymal volume replacement (PVR) by renal cell carcinoma (RCC) prior to intervention. This phenomenon is well-recognized yet not adequately studied, and, if severe, can influence management.

MATERIALS AND METHODS

A retrospective review was performed of partial nephrectomy (PN) and radical nephrectomy (RN) patients with available preoperative nuclear-renal-scan and imaging demonstrating solitary RCC with normal contralateral kidney. Normal renal parenchymal volume of each kidney was measured by free-hand scripting from preoperative axial images. Primary endpoint was percent PVR which was estimated assuming that the contralateral-kidney serves as a control: PVR = (volume contralateral kidney - volume ipsilateral kidney) normalized by volume contralateral kidney. Multivariable linear-regression analysis assessed factors associated with preoperative PVR. Further analysis evaluated the functional effect of PVR prior to surgery.

RESULTS

146 PN and 136 RN patients with necessary studies were analyzed. For RN, the median PVR was 15% and a quarter of patients had PVR ≥27%. In contrast, PVR was negligible in PN patients for whom median preoperative parenchymal volumes were nearly identical in the ipsilateral/contralateral kidneys (179/180cc, respectively). PVR inversely correlated with preoperative renal function in the ipsilateral kidney (P <.01). Tumor-size (P <.01), stage (P = .03), and endophytic properties (P = .03) associated with PVR on multivariable-analysis.

CONCLUSION

Our data suggest that substantial replacement of normal parenchyma by RCC occurs in many patients selected for RN and can contribute to preexisting renal-insufficiency. PVR prior to intervention is mainly driven by tumor characteristics in RN patients, but is negligible in most PN patients.

Three-dimensional (3D) reconstruction and navigation in robotic-assisted partial nephrectomy (RAPN) for renal masses in the solitary kidney: A comparative study

BACKGROUND

Numerous efforts were made to improve renal function and oncologic outcomes in surgery for patients with kidney cancer. We explored new robotic methods in solitary kidneys.

MATERIALS AND METHODS

We prospectively registered and included 16 patients in the 3D-robot-assisted partial nephrectomy (RAPN) group with a solitary kidney (anatomic or functional), and retrospectively identified 25 patients with a solitary kidney who received RAPN also operated by us for comparison.

RESULTS

The rates of global clamping reduced in the 3D-RAPN group (37.5% vs 76%)while selective rates were higher (56.2% vs 20%) (p = 0.028). The mean percentages of Scr increase (+20.2% vs +30.2%, p = 0.045) and eGFR reduction (-16.8% vs -27.1%) as well as rate of opening collecting systems (31.3% vs 72%, p = 0.010) were lower in 3D-RAPN group.

CONCLUSIONS

3D-RAPN less impaired the renal function of patients with a solitary kidney and showed superiority or non-inferiority in other evaluation indexes compared to conventional RAPN.

A Nomogram for the Prediction of Intermediate Significant Renal Function Loss After Robot-assisted Partial Nephrectomy for Localized Renal Tumors: A Prospective Multicenter Observational Study (RECORd2 Project)

BACKGROUND

Robot-assisted partial nephrectomy (RAPN) is increasingly adopted for the treatment of localized renal tumors; however, rates and predictors of significant renal function (RF) loss after RAPN are still poorly investigated, especially at a long-term evaluation.

OBJECTIVE

To analyze the predictive factors and develop a clinical nomogram for predicting the likelihood of ultimate RF loss after RAPN.

DESIGN, SETTING, AND PARTICIPANTS

We prospectively evaluated all patients treated with RAPN in a multicenter series (RECORd2 project).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Significant RF loss was defined as >25% reduction in estimated glomerular filtration rate (eGFR) from preoperative assessment at 48th month follow-up after surgery. Uni- and multivariable logistic regression analyses for RF loss were performed. The area under the receiving operator characteristic curve (AUC) was used to quantify predictive discrimination. A nomogram was created from the multivariable model.

RESULTS AND LIMITATIONS

A total of 981 patients were included. The median age at surgery was 64.2 (interquartile range [IQR] 54.3-71.4) yr, and 62.4% of patients were male. The median Charlson Comorbidity Index (CCI) was 1 (IQR 0-2), 12.9% of patients suffered from diabetes mellitus, and 18.6% of patients showed peripheral vascular disease (PVD). The median Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score was 7 (IQR 7-9). Imperative indications to partial nephrectomy were present in 3.6% of patients. Significant RF loss at 48th month postoperative evaluation was registered in 108 (11%) patients. At multivariable analysis, age (p = 0.04), female gender (p < 0.0001), CCI (p < 0.0001), CCI (p < 0.0001), diabetes (p < 0.0001), PVD (p < 0.0001), eGFR (p = 0.02), imperative (p = 0.001) surgical indication, and PADUA score (p < 0.0001) were found to be predictors of RF loss. The developed nomogram including these variables showed an AUC of 0.816.

CONCLUSIONS

We developed a clinical nomogram for the prediction of late RF loss after RAPN using preoperative and surgical variables from a large multicenter dataset.

PATIENT SUMMARY

We developed a nomogram that could represent a clinical tool for early detection of patients at the highest risk of significant renal function impairment after robotic conservative surgery for renal tumors.

Machine learning-based prediction of acute kidney injury after nephrectomy in patients with renal cell carcinoma

The precise prediction of acute kidney injury (AKI) after nephrectomy for renal cell carcinoma (RCC) is an important issue because of its relationship with subsequent kidney dysfunction and high mortality. Herein we addressed whether machine learning (ML) algorithms could predict postoperative AKI risk better than conventional logistic regression (LR) models. A total of 4104 RCC patients who had undergone unilateral nephrectomy from January 2003 to December 2017 were reviewed. ML models such as support vector machine, random forest, extreme gradient boosting, and light gradient boosting machine (LightGBM) were developed, and their performance based on the area under the receiver operating characteristic curve, accuracy, and F1 score was compared with that of the LR-based scoring model. Postoperative AKI developed in 1167 patients (28.4%). All the ML models had higher performance index values than the LR-based scoring model. Among them, the LightGBM model had the highest value of 0.810 (0.783-0.837). The decision curve analysis demonstrated a greater net benefit of the ML models than the LR-based scoring model over all the ranges of threshold probabilities. The application of ML algorithms improves the predictability of AKI after nephrectomy for RCC, and these models perform better than conventional LR-based models.

Evolution of renal function in patients with CT1 renal tumors after laparoscopic partial and radical nephrectomy. Predictive factors for renal function impairment

INTRODUCTION AND OBJECTIVES

To analyze the evolution of kidney function after laparoscopic partial nephrectomy (PN) and radical nephrectomy (RN) and to identify predictive factors for deterioration in kidney function.

MATERIALS AND METHOD

Retrospective study of patients with two kidneys, glomerular filtration rate (GFR) > 60 mL/min/1.73 m2, and single renal tumor cT1, treated in our center between 2005 and 2018.

RESULTS

A total of 372 patients met the inclusion criteria for the study; 156 (41.9%) were treated by RN and 216 (58.1%) by PN. There was a difference of 26.75 mL/min/1.73 m2 in GFR between RN and PN at discharge. Age > 60 years, postoperative complications (OR 2.97, p = 0.005) and RN (OR 10.03, p = 0.0001) were predictors of GFR < 60 mL/min/1.73 m2 at discharge. Only RN (OR 7.69, p = 0.0001) behaved as an independent prognostic factor for GFR < 45 mL/min/1.73m2 at discharge. The median follow-up of the series was 57 (IQR 28-100) months. At the end of the follow-up period, nine (6%) patients treated with RN developed severe chronic kidney disease (CKD) and three (2%) developed end stage renal disease (ESRD). Age > 70 years, diabetes mellitus (DM) (HR 2.12, p = 0.001), arterial hypertension (AHT) (HR 1.73, p = 0.01) and RN (HR 2.88, p = 0.0001) behaved as independent predictors of GFR < 60 mL/min/1.73 m2. The independent predictors for GFR< 45 mL/min/1.73m2 were age >70 years, DM (HR 1.99 CI 95% 1.04-3.83, p = 0.04) and RN (HR 5.88 CI 95% 2.57-13.45, p = 0.0001).

CONCLUSIONS

RN is a short- and long-term risk factor for CKD, although with a low probability of severe CKD or ESRD in patients with preoperative GFR > 60 mL/min/1.73 m2. Age, DM and AHT contribute to worsening renal function during follow-up.

Is off-clamp robot-assisted partial nephrectomy beneficial for renal function? Data from the CLOCK trial

OBJECTIVES

To compare the functional outcomes of on- vs off-clamp robot-assisted partial nephrectomy (RAPN) within a randomized controlled trial (RCT).

MATERIALS AND METHODS

The CLOCK study (CLamp vs Off Clamp the Kidney during robotic partial nephrectomy; NCT02287987) is a multicentre RCT including patients with normal baseline function, two kidneys and masses with RENAL scores ≤ 10. Pre- and postoperative renal scintigraphy was prescribed. Renal defatting and hilum isolation were required in both study arms; in the on-clamp arm, ischaemia was imposed until the completion of medullary renorraphy, while in the off-clamp condition it was not allowed throughout the procedure. The primary endpoint was 6-month absolute variation in estimated glomerular filtration rate (AV-GFR); secondary endpoints were: 12, 18 and 24-month AV-GFR; 6-month estimated glomerular filtration rate variation >25% rate (RV-GFR >25); and absolute variation in ipsilateral split renal function (AV-SRF). The planned sample size was 102 + 102 cases, after taking account crossover of cases to the alternate study arm; a 1:1 randomization was performed. AV-GFR and AV-SRF were compared using analysis of covariation, and RV-GFR >25 was assessed using multivariable logistic regression. Intention-to-treat (ITT) and per-protocol analyses (PP) were performed.

RESULTS

A total of 160 and 164 patients were randomly assigned to on- and off-clamp RAPN, respectively; crossover was observed in 14% and 43% of the on- and off-clamp arms, respectively. We were unable to find any statistically significant difference between on- vs off-clamp with regard to the primary endpoint (ITT: 6-month AV-GFR -6.2 vs -5.1 mL/min, mean difference 0.2 mL/min, 95% confidence interval [CI] -3.1 to 3.4 [P = 0.8]; PP: 6-month AV-GFR -6.8 vs -4.2 mL/min, mean difference 1.6 mL/min, 95% CI -2.3 to 5.5 [P = 0.7]) or with regard to the secondary endpoints. The median warm ischaemia time was 14 vs 15 min in the ITT analysis and 14 vs 0 min in the PP analysis.

CONCLUSION

In patients with regular baseline function and two kidneys, we found no evidence of differences in functional outcomes for on- vs off-clamp RAPN.

Factors affecting long-term renal functions after partial vs radical nephrectomy for clinical T1 renal masses: A Multicentre Study of the Urooncology Association, Turkey

PURPOSE

To compare the functional outcomes of patients who underwent partial (PN) or radical nephrectomy (RN) for clinical T1 (cT1) renal tumours using the Kidney Cancer Database of the Urooncology Association, Turkey.

METHODS

We retrospectively reviewed 1004 patients who underwent PN and RN for cT1 renal tumours at multiple academic tertiary centres between 2000 and 2018. Patients with preoperative end-stage chronic kidney disease and/or metastatic disease were excluded.

RESULTS

There were 452 patients in the PN group and 552 patients in the RN group. The median follow-ups were 74.9 and 83.7 months in RN and PN cohort. The eGFR was significantly reduced in both groups on postoperative day 1 (PN = 13.7 vs RN = 19.1 mL/min/1.73 m² : P < .001). In the PN group, eGFR showed a tendency to recover according to a quadratic pattern and reached preoperative levels in the first and third years (95.6 ± 28.8 mL/min/1.73 m² and 96.9 ± 28.9 mL/min/1.73 m² , respectively), with no significant difference between the eGFRs in the 1st and 3rd years (P = .710). To define groups at risk, different cut-off values for the GFR were considered. Among patients with a baseline GFR < 90, the RN cohort had significantly lower eGFRs in the first and third years than the PN cohort (P = .02). Logistic regression showed that comorbidities, coronary artery disease, diabetes and hypertension had no adverse impacts on the changes in the eGFR (P = .60, P = .13, and P = .13, respectively).

CONCLUSION

For the treatment of stage T1 kidney tumours, open or laparoscopic partial nephrectomy has the benefit to preserve renal function.

The impact of visceral adipose tissue on post -operative renal Function after Radical Nephrectomy for renal cell carcinoma

BACKGROUND

The objective of this study was to evaluate the usefulness of pre-operative visceral (VAT) and subcutaneous adipose tissue (SAT) evaluation in the prediction of Acute Kidney Injury (AKI) and decrease of eGFR at 12 months after radical nephrectomy (RN).

METHODS

We relied on 112 patients who underwent RN between January 2010 and March 2017 at a single institution. Images from the pre-operatory CT scan were analyzed and both SAT and VAT assessments were carried out on a cross-sectional plane. eGFR was measured before surgery, at 7 days, and 12 months after surgery. ROC analysis was used to compare the diagnostic value of BMI, VAT ratio, and abdominal circumference in predicting AKI. Logistic regression models were fitted to predict the new onset of AKI, and the progression from chronic kidney disease (CKD) stage 1-3a to CKD stage 3b or from 3b to 4 at 12 months follow-up. Two logistic regression models were also performed to assess the predictors for AKI and CKD stage progression. The predictive accuracy was quantified using the receiver operating characteristic-derived area under the curve.

RESULTS

Sixty-six patients (58.9%) had AKI after RN. Thirty-five (31.3%) patients were upgraded to CKD IIIb or from CKD stage IIIb to CKD IV. In the ROC analysis, VAT% performed better than the BMI and abdominal circumference (AUC = 0.66 vs 0.49 and 0.54, respectively). At multivariable analyses, VAT reached an independent predictor status for AKI (OR: 1.03) and for CKD stage at 12 months Follow-up (OR: 1.05). Inclusion of VAT% into the multivariable models was associated with the highest accuracy both for AKI (AUC = 0.700 vs 0.570) and CKD stage progression (AUC = 0.848 vs 0.800).

CONCLUSIONS

In patients undergoing RN, preoperative visceral adipose tissue ratio significantly predicts AKI incidence and is significantly predictive of 12 months CKD stage worsening.

Single-Port robot assisted partial nephrectomy: initial experience and technique with the da Vinci Single-Port platform (IDEAL Phase 1)

BACKGROUND

To evaluate the safety and feasibility of robotic-assisted laparoscopic partial nephrectomy (RAPN) performed using the da Vinci Single-Port (SP) platform.

METHODS

A retrospective review was conducted from December 2018 to December 2019 of 14 consecutive patients with localized renal cancer who underwent SP robot-assisted partial nephrectomy at a single institution. The procedures were performed by 2 experienced robotic surgeons, reproducing the steps of the standard multiport robotic approach to partial nephrectomy. A transperitoneal approach was utilized with a 2.5 cm para-rectus incision with one assistant 12 mm laparoscopic port.

RESULTS

No conversions to open or laparoscopic surgery occurred and no additional laparoscopic assistant ports were required. The median total operative time was 202 (162-231) minutes and the median total room time was 258 (215-295) minutes. The warm ischemia time averaged 20 minutes ± 8 minutes. 2 patients required angioembolization due to postoperative acute bleeding (Clavien-Dindo Grade 3a complication). Trifecta outcome (<25 min warm ischemia, no perioperative complications and negative margins) was achieved in 79% of patients. In one case, a positive margin was present. The median length of stay was of 1 day (Interquartile Range 1-2) with a median pain score on postoperative day 1 of 3.5 (Interquartile Range 2.4-5). 1/14 (7%) patient needed narcotic use at one week from discharge. At a median follow up of 5.0 (4.0-8.0) months, no patients have had evidence of disease recurrence.

CONCLUSIONS

In this initial cohort, considering the introduction of a new technology, we observed satisfactory outcomes for several key perioperative variables including operative time, warm ischemia time, surgical margins, hospital stay, pain requirements in patients undergoing RAPN with the SP platform. For experienced robotic surgeons, RAPN with the SP platform is a safe and feasible approach for single site partial nephrectomy.

Acute kidney injury strongly influences renal function after radical nephroureterectomy for upper tract urothelial carcinoma: A single-centre experience

OBJECTIVE

The aim of our study was to investigate frequency and predictors both of postoperative acute kidney injury (AKI) and renal function decline in a population of consecutive upper tract urothelial carcinoma (UTUC) patients who underwent radical nephroureterectomy (RNU).

MATERIALS AND METHODS

Between October 2014 and February 2020, 93 patients underwent RNU at our Institution. After considered exclusion criteria, 89 patients were selected. Perioperative clinical factors were retrospectively collected. Estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKDEPI) equation. We defined AKI as an increase in serum creatinine by ≥ 0.3 mg/dl or a 1.5-1.9-fold increase in serum creatinine from baseline to I post-operative day (POD). A significant renal function reduction was defined as an eGFR reduction of 40% from baseline at discharge and at last clinical evaluation. Frequency of AKI and eGFR decline was investigated. Association between perioperative clinical factors and AKI and eGFR reduction at discharged and last follow-up was studied using univariate and multivariate models.

RESULTS

AKI was detected at I POD in 45 patients. On multivariate analysis, pre-operative eGFR was an independent predictor of AKI (OR 1.03; p = 0.042). Further, AKI was found to be a significant predictor of eGFR reduction ≥ 40% at discharge at univariate analysis (OR 19.42; p = 0.005) and at multivariate analysis (OR 12.49; p = 0.02). In a multivariate logistic regression model post-operative AKI (OR 5.18; p = 0.033), lack of ipsilateral preoperative hydronephrosis (OR 0.17; p = 0.016), preoperative eGFR (OR 1.04; p = 0.047) and antiplatelet therapy (OR 5.14; p = 0.018) were found to be independent predictors of an eGFR reduction higher than 40% at last clinical evaluation made at a median of 15 (IQR 5-30) months.

CONCLUSIONS

In our cohort, AKI was present in almost 50% of patients after RNU and it was a strong predictor of renal function decline after RNU.

Does Reduced Renal Function Predispose to Cancer-specific Mortality from Renal Cell Carcinoma?

BACKGROUND

Recent publications have reported an association between increased renal cancer-specific mortality (CSM) and reduced renal function "below safety limits," and advocated for partial nephrectomy (PN) even for potentially aggressive/complex tumors. We hypothesize that this association may be related to confounding factors rather than a consequence of functional differences.

OBJECTIVE

To assess whether there is an independent association between preoperative estimated glomerular filtration rate (eGFR) or new baseline eGFR (NB-GFR) and CSM in patients undergoing PN or radical nephrectomy (RN).

DESIGN, SETTING, AND PARTICIPANTS

A single-center retrospective review was performed. All clinically and pathologically confirmed T1-T3a/N0/M0 renal cancer patients undergoing PN/RN (1999-2008, n = 1605) with adequate functional/oncological data were included.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was CSM. Secondary endpoints were cancer recurrence (CR) and all-cause mortality (ACM). Cox regression analyses investigated endpoints and predictive factors.

RESULTS AND LIMITATIONS

The median age was 60 yr and 64% of patients were male. Comorbidities included hypertension (60%), cardiovascular disease (19%), diabetes (21%), and chronic kidney disease (22%). PN was performed in 954 patients (59%). The median preoperative eGFR and NB-GFR were 80 and 60 ml/min/1.73 m², respectively. Median tumor diameter was 3.6 cm (interquartile range [IQR] = 2.4, 5.5); 70% of tumors were clear cell and 40% were of high grade. Pathology revealed pT1-2/N0/M0 and pT3a/N0/M0 in 81% and 19%, respectively. The median follow-up among survivors was 11.5 yr (IQR = 4, 14). Cancer-specific survival, recurrence-free survival, and overall survival were 94%, 88%, and 73% at 10 yr, respectively. On multivariable analysis, increased age (hazard ratio [HR] = 1.03, p =  0.04), increased tumor size (HR = 1.24, p <  0.01), tumor grade 3/4 (HR = 3.17, p <  0.01), and clear-cell histology (HR = 2.92, p <  0.01) were associated with increased hazard of CSM. Neither preoperative eGFR nor NB-GFR was significantly associated with CSM or CR (all p >  0.1), while an increased preoperative eGFR was associated with reduced hazard of ACM (HR = 0.87, p <  0.01). Limitations include retrospective design and a potential selection bias.

CONCLUSIONS

Our data do not support oncological protection of greater preservation of renal function and confirm that unfavorable oncological outcomes for localized RCC are mostly associated with aggressive tumor characteristics.

PATIENT SUMMARY

We did not find an association between greater preservation of renal function and oncological outcomes for kidney cancer.

The role of open radical nephrectomy in contemporary management of renal cell carcinoma

Radical nephrectomy (RN) remains a cornerstone of the management of localised renal cell carcinoma (RCC). RN involves the en bloc removal of the kidney along with perinephric fat enclosed within Gerota's fascia. Key principles of open RN include appropriate incision for adequate exposure, dissection and visualisation of the renal hilum, and early ligation of the renal artery and subsequently renal vein. Regional lymph node dissection (LND) facilitates local staging but its therapeutic role remains controversial. LND is recommended in patients with high risk clinically localised disease, but its benefit in low risk node-negative and clinically node-positive patients is unclear. Concomitant adrenalectomy should be reserved for patients with large tumours with radiographic evidence of adrenal involvement. Despite a recent downtrend in utilisation of open RN due to nephron-sparing and minimally invasive alternatives, there remains a vital role for open RN in the management of RCC in three domains. Firstly, open RN is important to the management of large, complex tumours which would be at high risk of complications if treated with partial nephrectomy (PN). Secondly, open RN plays a crucial role in cytoreductive nephrectomy (CN) for metastatic RCC, in which the laparoscopic approach achieves similar results but is associated with a high reoperation rate. Finally, open RN is the current standard of care in the management of inferior vena caval (IVC) tumour thrombus. Management of tumour thrombus requires a multidisciplinary approach and varies with cranial extent of thrombus. Higher level thrombus may require hepatic mobilisation and circulatory support, whilst the presence of bland thrombus may warrant post-operative filter insertion or ligation of the IVC.

Is partial nephrectomy safe and effective in the setting of frail comorbid patients affected by renal cell carcinoma? Insights from the RECORD 2 multicentre prospective study

BACKGROUND

To investigate the perioperative and morbidity outcomes after partial nephrectomy (PN) in patients with short life expectancy (SLE) (≥95% 10-year expected mortality (10y-EM)), to assess the main predictors of outcomes in this population and to compare these results with those of a group at the opposite upper range with long LE (LLE, ≤5% 10y-EM) relying on a multicenter Italian prospective registry of kidney surgery (the RECORD 2 project).

METHODS

Clinical data of 4,325 patients undergone kidney surgery were collected at 26 urological Italian Centers from 2013 to 2016. SLE was defined as a ≥95% 10y-EM (assessed using the age-adjusted Charlson comorbidity index [CCI]). A multivariable logistic regression for overall postoperative complications, acute kidney injury (AKI), positive surgical margins (SM) and ∆ estimated glomerular filtration rate (eGFR) ≥25% at 2 years from surgery was performed in patients with SLE including clinically relevant variables. Adjusted outcomes reported as mean (SD) of the 2 groups were generated using separate multivariable logistic regression models and compared.

RESULTS

Overall, 559 patients with SLE were selected. Patients had an ASA score ≥3 in 58.4% of cases. A clinical T1a, T1b, and T2 stage was found in 412 (74.5%), 124 (22.4%), and 17 (3.1%) patients. The median PADUA score was 7 (6-8). Surgical and medical postoperative complication rates were registered in 14.8% and 6% cases. Postoperative AKI was reported in 27.3% cases, positive surgical margins (PSM) in 9.3% cases. In this subgroup of patients, ASA score, cerebrovascular disease, surgery in low volume centers, and open surgery were independent predictors of overall complications. ASA and PADUA scores, renal clamping, resection technique and lower eGFR at baseline were independent predictors of AKI. PADUA score, open approach and resection technique were independent predictors of PSM. Cardiovascular disease, hilar clamping, and resection technique were independent predictors of eGFR decrease >25% at 2 years from surgery. Patients with SLE were compared with those with LLE (n = 302). All analyzed parameters at baseline were significantly different among the groups with the exception of cancer laterality. After adjusting for several clinical variables, the SLE group had a significantly higher risk rate of adjusted overall postoperative complication rate compared to the LLE group (20.6% ± 0.36 vs. 9.9% ± 0.65, P < 0.0001), while the overall intraoperative complications (4.1% ±0.13 vs. 2.3% ± 0.23), overall postoperative major complications (3.8% ± 0.09 vs. 1.9% ± 0.14) adjusted AKI (24.2% ± 0.37 vs. 22.6% ± 0.92), positive surgical margins (8% ± 0.22 vs. 6.4% ± 0.49), and 2-year RF loss (13.4% ± 0.17 vs. 12.4% ± 0.74).

CONCLUSION

In selected patients with SLE, PN is feasible with an acceptable safety profile that is overall comparable to patients with no LE limitations. While a robotic approach and surgery performed in high volume centers could reduce the risk of complications, an off-clamp approach and a SE surgical technique may decrease the risk of postoperative AKI and of longer term eGFR decrease.