Robotic-assisted Partial Nephrectomy for "Very Small" (<2 cm) Renal Mass: Results of a Multicenter Contemporary Cohort

Da Vinci and Hugo RAS Platforms for robot-assisted partial nephrectomy: a preliminary prospective comparative analysis of the outcomes

BACKGROUND

Robot-assisted partial nephrectomy (RAPN) has emerged as the preferred approach for T1 renal-cell-carcinoma. As new robotic platforms like Hugo RAS emerge, we seek to understand their potential in achieving similar RAPN outcomes as the established Da Vinci system.

METHODS

A prospective single-center comparative study was conducted, and 50 patients selected for RAPN were enrolled (25 Da Vinci Xi; 25 Hugo RAS). The choice of robotic system was based solely on hospital logistics criteria. Surgeries were performed by expert surgeons. Demographic data, tumor characteristics, operative details and postoperative outcomes were collected. SPSS version 22.0 was used for statistical analyses.

RESULTS

The average age of patients was 62.52±9.47 years, with no significant differences in median age, sex, and nephrometry scores between groups. Da Vinci group showed a significantly shorter docking time (12.56 vs. 20.08 min; P<0.01), while other intraoperative measures like console time and warm ischemia time were similar. The Hugo RAS group had a shorter renorraphy time (14.33 vs. 18.84 min; P=0.024). Postoperative outcomes and surgical margin positivity showed no significant differences. Each group had one patient (4%) who developed major surgical complications (Clavien IIIa). Trifecta rates were comparable between both groups (Da Vinci 88% vs. Hugo RAS 84%; P=0.93).

CONCLUSIONS

Initial findings suggest similar perioperative outcomes for RAPN when using Hugo RAS compared to the Da Vinci system. Further research with long-term follow-up is necessary to evaluate oncological and functional outcomes.

Comparison of the perioperative outcomes of robot-assisted laparoscopic transperitoneal versus retraperitoneal partial nephrectomy for posterior-lateral renal tumors: a systematic review and meta-analysis

The study aims to assess the available literature and compare the perioperative outcomes of robotic-assisted partial nephrectomy (RAPN) for posterior-lateral renal tumors using transperitoneal (TP) and retroperitoneal (RP) approaches. Systematically searched the Embase, PubMed, and Cochrane Library databases for literature. Eligible studies were those that compared TP-RAPN and RP-RAPN for posterior-lateral renal tumors. The data from the included studies were analyzed and summarized using Review Manager 5.3, which involved comparing baseline patient and tumor characteristics, intraoperative and postoperative outcomes, and oncological outcomes. The analysis included five studies meeting the inclusion criteria, with a total of 1440 patients (814 undergoing RP-RAPN and 626 undergoing TP-RAPN). Both groups showed no significant differences in age, gender, BMI, R.E.N.A.L. score, and tumor size. Notably, compared to TP-RAPN, the RP-RAPN group demonstrated shorter operative time (OT) (MD: 17.25, P = 0.01), length of hospital stay (LOS) (MD: 0.37, P < 0.01), and lower estimated blood loss (EBL) (MD: 15.29, P < 0.01). However, no significant differences were found between the two groups in terms of warm ischemia time (WIT) (MD: -0.34, P = 0.69), overall complications (RR: 1.25, P = 0.09), major complications (the Clavien-Dindo classification ≥ 3) (RR: 0.97, P = 0.93), and positive surgical margin (PSM) (RR: 1.06, P = 0.87). The systematic review and meta-analysis suggests RP-RAPN may be more advantageous for posterior-lateral renal tumors in terms of OT, EBL, and LOS, but no significant differences were found in WIT, overall complications, major complications, and PSM. Both surgical approaches are safe, but a definitive advantage remains uncertain.

Assessing the Trade-off Between the Safety and Effectiveness of Off-clamp Robotic Partial Nephrectomy for Renal Masses with a High RENAL Score: A Propensity Score-matched Comparison of Perioperative and Functional Outcomes in a Multicenter Analysis

BACKGROUND

Tumors with a high nephrometry score represent a challenging surgical scenario for which robotic partial nephrectomy (RPN) is a primary option in expert hands.

OBJECTIVE

To compare perioperative and functional outcomes of off-clamp and on-clamp RPN in patients with renal masses with a high RENAL score (≥9).

DESIGN, SETTING, AND PARTICIPANTS

For this retrospective analysis, an RPN data set including 1604 patients treated at three institutions between 2003 and 2021 was queried for cases with a RENAL score ≥9.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We used 1:1 propensity score matching (PSM) to select a cohort in which imbalances between the off-clamp and on-clamp groups were minimized. We used χ2 and Student t tests to compare categorical and continuous variables, respectively. The Kaplan-Meier method was used to compare the probability of having an estimated glomerular filtration rate (eGFR) ≥45 ml/min during follow-up. Univariable and multivariable analyses were performed to identify predictors of a trifecta outcome (negative surgical margin status, no Clavien-Dindo grade ≥3 complications, eGFR decline ≤30%) and of retaining eGFR ≥45 ml/min over time.

RESULTS AND LIMITATIONS

From an overall cohort of 354 patients (142 on-clamp, 212 off-clamp), a homogeneous PSM cohort of 78 patients in each group was selected (p ≥ 0.17). In the PSM cohort, operative time was significantly shorter in the off-clamp group (p < 0.001). There were no differences between the groups in the rates of severe complications (p = 0.32) and positive surgical margins (p = 0.24). The rate of trifecta achievement was significantly higher in the off-clamp group (83.3% vs 67.9%; p = 0.03). Warm ischemia time >20 min was independently negatively associated with trifecta achievement (odds ratio 0.32, 95% confidence interval 0.14-0.74). Moreover, the off-clamp group had a significantly higher probability of retaining eGFR ≥45 ml/min over time (3 yr: 95.9% vs 81.6%; p = 0.03); every 1-min increase in warm ischemia time reduced this probability by 1.3%.

CONCLUSIONS

We found a favorable trade-off between the benefits and risks of off-clamp RPN, with similar perioperative outcomes and a net benefit in terms of trifecta achievement and long-term renal function outcomes in comparison to on-clamp RPN.

PATIENT SUMMARY

The complexity of surgery for kidney tumors can be assessed using the RENAL score, which is a measure of the location and size of a kidney tumor. In a multicenter series of patients with tumors with a high RENAL score, we compared outcomes between strategies with (on-clamp) and without (off-clamp) clamping of kidney blood vessels during robot-assisted removal of part of the affected kidney. We found that off-clamp surgery results in better postoperative kidney function.

Alkaline phosphatase combines with CT factors for differentiating small (≤ 4 cm) fat-poor angiomyolipoma from renal cell carcinoma: a multiple quantitative tool

PURPOSE

This study aimed to evaluate the diagnostic value of serum and CT factors to establish a convenient diagnostic method for differentiating small (≤ 4 cm) fat-poor angiomyolipoma (AML) from renal cell carcinoma (RCC).

MATERIALS AND METHODS

This study analyzed the preoperative serum laboratory data and CT data of 32 fat-poor AML patients and 133 RCC patients. The CT attenuation value of tumor (AVT), relative enhancement ratio (RER), and heterogeneous degree of tumor were detected using region of interest on precontrast phase (PCP) and the corticomedullary phase. Multivariate regression was performed to filter the main factors. The main factors were selected to establish the prediction models. The area under the curve (AUC) was measured to evaluate the diagnostic efficacy.

RESULTS

Fat-poor AML was more common found in younger (47.91 ± 2.09 years vs 53.63 ± 1.17 years, P = 0.02) and female (70.68 vs 28.13%, P < 0.001) patients. Alkaline phosphatase (ALP) was higher in RCC patients (81.80 ± 1.75 vs 63.25 ± 2.95 U/L, P < 0.01). For CT factors, fat-poor AML was higher in PCP_AVT (40.30 ± 1.49 vs 32.98 ± 0.69Hu, P < 0.01) but lower in RER (67.17 ± 3.17 vs 84.64 ± 2.73, P < 0.01). Gender, ALP, PCP_AVT and RER was found valuable for the differentiation. When compared with laboratory-based or CT-based diagnostic models, the combination model integrating gender, ALP, PCP_AVT and RER shows the best diagnostic performance (AUC = 0.922).

CONCLUSION

ALP was found higher in RCC patients. Female patients with ALP < 70.50U/L, PCP_AVT > 35.97Hu and RER < 82.66 are more likely to be diagnose as fat-poor AML.

Percutaneous Ablation vs Robot-Assisted Partial Nephrectomy for Completely Endophytic Renal Masses: A Multicenter Trifecta Analysis with a Minimum 3-Year Follow-Up

Purpose: To compare outcomes of robot-assisted partial nephrectomy (RAPN) and percutaneous tumor ablation (PTA) for completely endophytic renal masses. Methods: Data of patients who underwent RAPN or PTA for treatment of completely endophytic (three points for "E" domain of R.E.N.A.L. score) were collected from seven high-volume U.S. and European centers. PTA included cryoablation, radiofrequency, or microwave ablation. Baseline characteristics, clinical, surgical, and postoperative outcomes were compared. Recurrence-free survival (RFS) was calculated with Kaplan-Meier analysis. Trifecta was used as arbitrary combined outcome parameter as proxy for treatment "quality." Multivariable logistic regression model assessed predictors of trifecta failure. Results: One hundred fifty-two patients (RAPN, n = 60; PTA, n = 92) were included in the analysis. RAPN group was younger (p < 0.001), had lower American Society of Anesthesiologists score (p = 0.002), and higher baseline estimated glomerular filtration rate (p < 0.001). There was no difference in clinical tumor size, clinical T stage, and tumor complexity scores. PTA had significantly lower rate of overall (p < 0.001) and minor (p < 0.001) complications. ΔeGFR at 1 year was statistically higher for RAPN (-15.5 mL/min vs -3.1 mL/min; p = 0.005), no difference in ΔeGFR at last follow-up (p = 0.22) was observed. No difference in recurrences (RAPN, n = 2; PTA, n = 6) and RFS was found (p = 0.154). Trifecta achievement was higher for RAPN but not statistically different (65.3% vs 58.8%; p = 0.477). R.E.N.A.L. Nephrometry Score resulted predictive of trifecta failure (odds ratio = 1.47; confidence interval = 1.13-1.90; p = 0.004). Conclusions: PTA confirms to be an effective treatment for completely endophytic renal masses, offering low complications and good mid-term functional and oncologic outcomes. These outcomes compare favorably with those of RAPN, which seem to be the preferred option for younger and less comorbid patients.

Robot-Assisted Partial Nephrectomy Mid-Term Oncologic Outcomes: A Systematic Review

Background: Robot-assisted partial nephrectomy (RAPN) is used more and more in present days as a therapy option for surgical treatment of cT1 renal masses. Current guidelines equally recommend open (OPN), laparoscopic (LPN), or robotic partial nephrectomy (PN). The aim of this review was to analyze the most representative RAPN series in terms of reported oncological outcomes. (2) Methods: A systematic search of Webofscience, PUBMED, Clinicaltrials.gov was performed on 1 August 2022. Studies were considered eligible if they: included patients with renal cell carcinoma (RCC) stage T1, were prospective, used randomized clinical trials (RCT) or retrospective studies, had patients undergo RAPN with a minimum follow-up of 48 months. (3) Results: Reported positive surgical margin rates were from 0 to 10.5%. Local recurrence occurred in up to 3.6% of patients. Distant metastases were reported in up to 6.4% of patients. 5-year cancer free survival (CFS) estimates rates ranged from 86.4% to 98.4%. 5-year cancer specific survival (CSS) estimates rates ranged from 90.1% to 100%, and 5-year overall survival (OS) estimates rated ranged from 82.6% to 97.9%. (4) Conclusions: Data coming from retrospective and prospective series shows very good oncologic outcomes after RAPN. Up to now, 10-year survival outcomes were not reported. Taken together, RAPN deliver similar oncologic performance to OPN and LPN.

Updates in Grading of Renal Cell Carcinomas Beyond Clear Cell Renal Cell Carcinoma and Papillary Renal Cell Carcinoma

The World Health Organization (WHO) recommends grading of clear cell renal cell carcinoma (RCC) and papillary RCC using the WHO/International Society of Urological Pathology (ISUP) grade, which is primarily based on nuclear features. As the spectrum of RCC continues to evolve, with more recently described subtypes in the past decade, literature evidence on grading these subtypes is limited or not available for some tumor types. Herein, we outline a pragmatic approach to the topic of grading RCC, dividing the contemporarily described RCC subtypes into 7 categories based on the potential clinical applicability of grading as a useful prognostic parameter: (1) RCC subtypes that are reasonably validated and recommended for WHO/ISUP grading; (2) RCC subtypes where WHO/ISUP is not applicable; (3) RCC subtypes where WHO/ISUP grading is potentially clinically useful; (4) inherently aggressive RCC subtypes where histologic classification itself confers an aggressive biologic potential; (5) renal epithelial tumors where WHO/ISUP grading provides potentially misleading prognostic implication; (6) renal epithelial neoplasms where low WHO/ISUP grade features are a prerequisite for accurate histologic classification; and (7) renal epithelial neoplasms with no or limited data on grading or incomplete understanding of the biologic potential. Our aim in outlining this approach is 2-fold: (a) identify the gaps in understanding and application of grading in RCC subtypes so that researchers in the field may perform additional studies on the basis of which the important pathologic function of assignment of grade may be recommended to be performed as a meaningful exercise across a wider spectrum of RCC; and (b) to provide guidance in the interim to surgical pathologists in terms of providing clinically useful grading information in RCC based on currently available clinicopathologic information.

Retroperitoneal versus transepritoneal robot-assisted partial nephrectomy for postero-lateral renal masses: an international multicenter analysis

PURPOSE

To assess the outcomes of retroperitoneal robot-assisted partial nephrectomy (r-RAPN) in a large cohort of patients with postero-lateral renal masses comparing to those of transperitoneal RAPN (t-RAPN).

METHODS

Patients with posterior (R.E.N.A.L. score grading P) or lateral (grading X) renal mass who underwent RAPN in six high-volume US and European centers were identified and stratified into two groups according to surgical approach: r-RAPN ("study group") and t-RAPN ("control group"). Baseline characteristics, intraoperative, and postoperative data were collected and compared.

RESULTS

Overall, 447 patients were identified for the analysis. 231 (51.7%) and 216 (48.3%) patients underwent r-RAPN and t-RAPN, respectively. Baseline characteristics were not statistically significantly different between the groups. r-RAPN group reported lower median operative time (140 vs. 170 min, p < 0.001). No difference was found in ischemia time, estimated blood loss, and intraoperative complications. Overall, 47 and 54 postoperative complications were observed in r-RAPN and t-RAPN groups, respectively (20.3 vs. 25.1%, p = 0.9). 1 and 2 patients reported major complications (Clavien-Dindo ≥ III grade) in the retroperitoneal and transperitoneal groups (0.4 vs. 0.9%, p = 0.9). There was no difference in hospital re-admission rate, median length of stay, and PSM rate. Trifecta criteria were achieved in 90.3 and 89.2% of r-RAPN and t-RAPN, respectively (p = 0.7).

CONCLUSION

r-RAPN and t-RAPN offer similar postoperative, functional, and oncological outcomes for patients with postero-lateral renal tumors. Our analysis suggests an advantage for r-RAPN in terms of shorter operative time, whereas it does not confirm a difference in terms of length of stay, as suggested by previous reports.

Oncological outcomes of active surveillance and percutaneous cryoablation of small renal masses are similar at intermediate term follow-up

BACKGROUND

Active surveillance (AS) and minimally invasive ablative therapies such as percutaneous cryoablation (PCA) are emerging as alternative treatment modalities in the management of small renal masses (SRMs).

METHODS

Fifty-nine patients underwent PCA since 2011 and 75 underwent AS since 2010 at two different institutions. Only patients with follow-up ≥ 6 months were included. All patients were followed with a standardized protocol. Treatment failure was defined by dimensional progression for AS and renal recurrence for PCA, in addition to stage and/or metastatic progression for both groups.

RESULTS

Treatment failure was observed in 14 cases (18,7%) during AS (mainly due to dimensional progression) and 12 patients (16%) underwent delayed intervention with a mean follow-up of 36,83 months. Seven patients (11,9%) in the PCA group experienced treatment failure with a mean follow-up of 33,39 months and 3 of them underwent re-ablation successfully. Cancer-specific-survival at 2 and 5 years was 100% and 95,8% in AS-group vs. 98,2% and 98,2% in PCA-group (p=0,831). One patient in both groups died from metastatic disease. Overall-survival at 2 and 5 years was 91,7% and 82,4% in the AS-group vs. 96,5% and 96,5% in the PCA-group (p=0,113). Failure-free survival at 2 and 5 years was 90,9% and 70,1% in the AS-group vs. 93,1% and 70,9% in the PCA-group (p=0,645).

CONCLUSIONS

AS and PCA provide similar survival outcomes and are safe and valid treatment options for elderly and comorbid patients with SRMs.