Robotic-assisted tumor enucleation versus standard margin partial nephrectomy: Perioperative, renal functional, and oncologic outcomes for low and intermediate complexity renal masses

ctDNA predicts clinical T1a to pathological T3a upstaging after partial nephrectomy

Most patients diagnosed with clear cell renal cell carcinoma (ccRCC) are also detected with small and organ-confined tumors, and the majority of these are classified as clinical tumor stage 1a (cT1a). A considerable proportion of patients with cT1 RCC shows tumor upstaging to pathological stage 3a (pT3a), and these patients have worse oncological outcomes. The role of circulating tumor DNA (ctDNA) in RCC has been limited to monitoring treatment response and resistance. Therefore, the present study aimed to evaluate the potential of ctDNA in predicting pT3a upstaging in cT1a ccRCC. We sequenced plasma samples preoperatively collected from 48 patients who had undergone partial nephrectomy for cT1a ccRCC using data from a prospective cohort RCC. The ctDNA were profiled and compared with clinicopathological ccRCC features to predict pT3a upstaging. Associations between ctDNA, tumor complexity, and pT3a upstaging were evaluated. Tumor complexity was assessed using the anatomical classification system. Univariate analysis used chi-squared and Student's t-tests; multivariate analysis considered significant factors from univariate analyses. Of the 48 patients with cT1a ccRCC, 12 (25%) were upstaged to pT3a, with ctDNA detected in 10 (20.8%), predominantly in patients with renal sinus fat invasion (SFI; n = 8). Among the pT3a group, ctDNA was detected in 75%, contrasting with only 2.8% in patients with pT1a (1/36). Detection of ctDNA was the only significant preoperative predictor of pT3a upstaging, especially in SFI. This study is the first to suggest ctDNA as a preoperative predictor of pT3a RCC upstaging from cT1a based on preoperative radiological images.

Robot-assisted Simple Enucleation Versus Standard Robot-assisted Partial Nephrectomy for Low- or Intermediate-complexity, Clinical T1 Renal Tumors: A Randomized Controlled Noninferiority Trial

BACKGROUND

Although partial nephrectomy has become the gold standard for T1 renal tumors whenever technically feasible, simple enucleation has shown superior results. To the best of our knowledge, no randomized controlled trials comparing these two surgical approaches have been published.

OBJECTIVE

To compare the surgical margin status for robot-assisted simple enucleation (RASE) and standard robot-assisted partial nephrectomy (sRAPN) for clinical T1 renal tumors.

DESIGN, SETTING, AND PARTICIPANTS

This is a prospective, randomized, controlled, noninferiority trial. A total of 380 patients aged 18-80 yr with newly diagnosed, sporadic, unilateral clinical T1 renal tumors (RENAL score <10) were enrolled and randomized to RASE or sRAPN. The primary endpoint was the positive surgical margin (PSM) rate, with a noninferiority margin of 7.5% set. The study was registered on ClinicalTrials.gov (NCT03624673).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We defined noninferiority for RASE versus standard RAPN as an upper 95% confidence interval (CI) bound of <7.5% for the difference in the proportion of patients with a PSM.

RESULTS AND LIMITATIONS

A cohort of 380 patients was enrolled and randomly assigned to RASE (n = 190) or sRAPN (n = 190). On intention-to-treat analysis for patients with malignant tumors, 2.3% of patients in the RASE group and 3.0% in the sRAPN group had a PSM. The RASE group showed noninferiority to the sRAPN group within a 7.5% margin (difference -0.7%, 95% CI -4.0% to 2.7%). Per-protocol analysis also demonstrated noninferiority of RASE. The RASE group had a shorter median operative time (145 vs 155 min; p = 0.018) and a lower rate of tumor bed suturing (8.9% vs 43%; p < 0.001) in comparison to the sRAPN group. Estimated blood loss was considerably lower in the sRAPN group than in the RASE group (p = 0.046). The rate of recurrence did not differ between the groups (p > 0.9).

CONCLUSIONS

RASE for the management of low- to intermediate-complexity tumors is noninferior to sRAPN in terms of the PSM rate. Long-term follow-up is needed to draw conclusions regarding oncological outcomes.

PATIENT SUMMARY

We carried out a trial to compare simple tumor enucleation versus partial nephrectomy for renal tumors. The outcome we assessed was the proportion of patients with a positive surgical margin. Our results show that simple tumor enucleation is not inferior to partial nephrectomy for this outcome. Longer follow-up is needed to assess other cancer control outcomes.

Robotic transperitoneal versus retroperitoneal approach for anterior renal mass nephron-sparing surgery

Robotic nephron-sparing surgery is traditionally performed via a transperitoneal (TP) approach. However, the retroperitoneal (RP) approach has gained popularity, particularly for posterolateral renal masses. The RP approach is associated with shorter operative time, less blood loss, and shorter length of stay, while preserving oncologic outcomes in selected masses. Here, we aim to assess the feasibility of the RP approach in excising anterior renal masses. Patients ≥ 18 years of age who underwent robotic nephron-sparing surgery for anterior renal masses were retrospectively identified (2008-2022). Baseline demographics, tumor characteristics, and perioperative data were collected and characterized based on TP vs RP approaches. Wilcoxon rank sum test and Pearson's Chi-squared test were used to compare continuous and categorical variables, respectively. Two hundred and sixteen patients were included-178 (82.4%) underwent TP approach and 38 (17.6%) underwent RP approach. Baseline demographics, preoperative tumor size, and renal nephrometry scores were similar. The RP approach was associated with shorter operative (150 vs 203 min, p < 0.001) and warm ischemia time (12 vs 21 min, p < 0.001), and less blood loss (20 vs 100 cc, p = 0.002) (Table 1). The RP approach was associated with shorter length of stay (1 vs 2 days, p < 0.001) and less total complications (5.3% vs 19.1%, p = 0.038). Major complication (Clavien-Dindo Grade > 3) rates were similar. There was no difference in positive surgical margin rates or pathologic characteristics. Robotic RP approach for nephron-sparing surgery is feasible for eligible anterior tumors and is associated with favorable perioperative outcomes with preserved negative surgical margin rates. Table 1 Patient baseline demographics Overall Transperitoneal Retroperitoneal p value Median/N IQR/% Median/N IQR/% Median/N IQR/% N 216 178 82.4% 38 17.6% Age (years) 60.5 (52.1-67.7) 60.4 (52.8-67.7) 61.6 (49.1-69.2) 0.393 Sex Male 126 58.3% 100 56.2% 26 68.4% Female 90 41.7% 78 43.8% 12 31.6% 0.165 Race White 162 75.0% 137 77.0% 25 65.8% Asian 4 1.9% 2 1.1% 2 5.3% Black 21 9.7% 18 10.1% 3 7.9% Hispanic 26 12.0% 18 10.1% 8 21.1% Other 2 0.9% 2 1.1% 0 0.0% 0.197 Body mass index (kg/m2)  < 25 32 14.8% 25 14.0% 7 18.4% 25-30 68 31.5% 55 30.9% 13 34.2% 30-35 60 27.8% 50 28.1% 10 26.3% 35 +  56 25.9% 48 27.0% 8 21.1% 0.808 Prior abdominal surgery Yes 118 54.6% 104 58.4% 14 36.8% No 98 45.4% 74 41.6% 24 63.2% 0.015 Prior kidney surgery Yes 10 4.6% 9 5.1% 1 2.6% No 206 95.4% 169 94.9% 37 97.4% 0.518 Chronic kidney disease stage ≥ 3 Yes 45 20.8% 38 21.3% 7 18.4% No 171 79.2% 140 78.7% 31 81.6% 0.687 Charlson comorbidity index 0 138 63.9% 116 65.2% 22 57.9% 1 46 21.3% 38 21.4% 8 21.1% 2 19 8.8% 13 7.3% 6 15.8%  ≥ 3 13 6.0% 11 6.2% 2 5.3% 0.412 Tumor size (cm) 2.7 (2-3.6) 2.8 (2-3.5) 2.55 (2-3.7) 0.796 Tumor laterality Left 100 46.3% 78 43.8% 22 57.9% Right 116 53.7% 100 56.2% 16 42.1% 0.114 Clinical T stage cT1a 186 86.1% 152 85.4% 34 89.5% cT1b 30 13.9% 26 14.6% 4 10.5% 0.509 RENAL Nephrometry score Low (4 to 6) 94 43.5% 76 42.7% 18 47.4% Intermediate (7 to 9) 112 51.9% 94 52.8% 18 47.4% High (≥ 10) 19 4.6% 8 4.5% 2 5.3% 0.829 TE tumor enucleation, SPN standard margin partial nephrectomy, IQR interquartile range.

Risk of pseudoaneurysm and bleeding complications after partial nephrectomy: comparison of tumor enucleation to standard margin technique

Partial nephrectomy (PN) is the gold standard for the resection of amenable small renal masses. Some surgeons have adopted tumor enucleation (TE) over the standard margin PN (SPN) technique based on preservation of healthy renal parenchyma by following the tumor pseudocapsule. However, TE may also confer additional advantages due to avoidance of sharp incision including reduction in perioperative and bleeding complications. Therefore, we evaluated the rate of pseudoaneurysms and other complications following TE vs. SPN. A retrospective cohort study of patients undergoing PN (TE and SPN) between 2008 and 2020 was conducted. Baseline characteristics were compared between the TE and SPN cohorts with univariable and multivariable logistic regression models. A total of 534 patients were included, 195 (36.5%) receiving TE and 339 (63.5%) SPN. There were no differences in baseline patient demographics. There was no difference in RENAL nephrometry scores between the two groups (p = 0.47). TE had lower rates of postoperative complications (11.3 vs. 21.5%, p = 0.002). TE had less bleeding complications (2.1 vs. 8.0%, p = 0.002) with no pseudoaneurysm events following TE compared to 12 following SPN (0.0 vs. 3.5%, p = 0.008). Need for interventional radiology largely reflected pseudoaneurysm differences (0 (0.0%) TE vs. 13 (3.8%) SPN, p = 0.006. Readmission occurred less often after TE vs. SPN (4.1 vs. 8.3%, p = 0.07). Patients receiving TE experienced no clinically significant pseudoaneurysm formation and were less likely to have any bleeding complication or major complication postoperatively. TE may be preferred when minimizing morbidity aligns with patient selection and preferences.

Redo Partial Nephrectomy for Local Recurrence After Previous Nephron-sparing Surgery. Surgical Insights and Oncologic Results from a High-volume Robotic Center

Background

The role of redo partial nephrectomy (PN) for recurrent renal cell carcinoma (RCC) is still overlooked.

Objective

To report our experience of salvage PN for local recurrence after previous nephron-sparing surgery (NSS).

Design setting and participants

We prospectively gathered data from patients treated with robotic redo PN for locally recurrent RCC after previous NSS from January 2017 to January 2023. The type of surgical resection technique was assigned to the pathologic specimen according to the surface-intermediate-base (SIB) score.

Surgical procedure

Redo PN was performed by using the Si Da Vinci robotic platform.

Measurements

Operative time, warm ischemia time, and intra- and postoperative complications were recorded. The severity of postoperative complications and tumor stage were evaluated.

Results and limitations

Overall, 26 patients entered the study. The median clinical diameter was 3.5 (interquartile range [IQR] 2.2-4.9) cm and the median Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score was 8 (IQR 7-9). In 14 (53.8%) cases, recurrence was at the level of previous tumor resection bed. The median operative time was 177 (IQR 148-200) min, and hilar clamping was performed in 14 (53.8%) cases with a median warm ischemia time of 16 (14.5-22) min. Pure enucleation (SIB score 0-1), hybrid enucleation (SIB score 2), and pure enucleoresection (SIB score 3) were recorded in 13 (50%), eight (30.8%), and five (19.2%) cases, respectively. The totality of recurrent RCC far from previous tumor resection bed received a SIB score of 0-1, while in 57.1% and 35.8% of recurrent RCC on previous tumor resection a hybrid enucleation and a pure enucleoresection were performed, respectively. At a median follow-up of 37 (IQR 16-45) mo, five (19%) patients experienced disease recurrence, being local and systemic in three (11.5%) and two (7.7%) patients, respectively.

Conclusions

Our study highlights the feasibility and safety of redo PN for the treatment of locally recurrent RCCs after NSS, either on previous tumor resection bed or elsewhere in the kidney.

Patient summary

Robotic redo partial nephrectomy is a challenging procedure. The surgeon needs to tailor the surgical strategy and tumor resection technique case by case, given the heterogeneity of clinical scenarios and the need to achieve maximal functional preservation while ensuring oncologic efficacy.

Clinical study of renal artery cold perfusion combined with laparoscopic nephron retention in the treatment of complex renal angiomyolipoma

Objective

The aim of this study is to summarize the surgical experience of renal artery cold perfusion combined with laparoscopic nephron preserving surgery for the treatment of complex renal angiomyolipoma and to evaluate the safety and feasibility of this surgical protocol.

Materials and methods

Clinical data of nine patients who received renal artery cold perfusion combined with laparoscopic nephron preserving surgery for complex renal angiomyolipoma in our hospital from February 2017 to August 2020 were retrospectively analyzed. The study parameters included imaging findings, total renal function before and after surgery, glomerular filtration rate (GFR) of affected kidney before and after surgery, and related complications.

Results

Eight of the nine patients successfully completed the operation, one patient was intolerant to renal artery balloon implantation, and the success rate of the operation was 88.89%. The mean maximum tumor diameter was 6.8 cm, and RENAL score was 7 points. Postoperative total renal function and GFR of the affected kidney had no significant changes compared with that before surgery, and imaging examination showed no tumor residue or recurrence.

Conclusion

This surgical procedure is safe and feasible for complex renal angiomyolipoma and can be used as a surgical option for renal hamartoma. The long-term effect needs to be confirmed by further studies.

Resection Techniques During Robotic Partial Nephrectomy: A Systematic Review

Context

The resection technique used to excise tumor during robotic partial nephrectomy (RPN) is of paramount importance in achieving optimal clinical outcomes.

Objective

To provide an overview of the different resection techniques used during RPN, and a pooled analysis of comparative studies.

Evidence acquisition

The systematic review was conducted according to established principles (PROSPERO: CRD42022371640) on November 7, 2022. A population (P: adult patients undergoing RPN), intervention (I: enucleation), comparator (C: enucleoresection or wedge resection), outcome (O: outcome measurements of interest), and study design (S) framework was prespecified to assess study eligibility. Studies reporting a detailed description of resection techniques and/or evaluating the impact of resection technique on outcomes of surgery were included.

Evidence synthesis

Resection techniques used during RPN can be broadly classified as resection (non-anatomic) or enucleation (anatomic). A standardized definition for these is lacking. Out of 20 studies retrieved, nine compared "standard" resection versus enucleation. A pooled analysis did not reveal significant differences in terms of operative time, ischemia time, blood loss, transfusions, or positive margins. Significant differences favoring enucleation were found for clamping management (odds ratio [OR] for renal artery clamping 3.51, 95% confidence interval [CI] 1.13-10.88; p = 0.03), overall complications (OR for occurrence 0.55, 95% CI 0.34-0.87; p = 0.01) major complications (OR for occurrence 0.39, 95% CI 0.19-0.79; p = 0.009), length of stay (weighted mean difference [WMD] -0.72 d, 95% CI -0.99 to -0.45; p < 0.001), and decrease in estimated glomerular filtration rate (WMD -2.64 ml/min, 95% CI -5.15 to -0.12; p = 0.04).

Conclusions

There is heterogeneity in the reporting of resection techniques used during RPN. The urological community must improve the quality of reporting and research produced accordingly. Positive margins are not specifically related to the resection technique. Focusing on studies comparing standard resection versus enucleation, advantages with tumor enucleation in terms of avoidance of artery clamping, overall/major complications, length of stay, and renal function were found. These data should be considered when planning the RPN resection strategy.

Patient summary

We reviewed studies on robotic surgery for partial kidney removal using different techniques to cut away the kidney tumor. We found that a technique called "enucleation" was associated with similar cancer control outcomes in comparison to the standard technique and had fewer complications, better kidney function after surgery, and a shorter hospital stay.

Robotic versus Laparoscopic Partial Nephrectomy in the New Era: Systematic Review

(1) Background: In recent years there have been advances in imaging techniques, in addition to progress in the surgery of renal tumors directed towards minimally invasive techniques. Thus, nephron-sparing surgery has become the gold standard for the treatment of T1 renal masses. The aim of this study is to investigate the benefits of robotic partial nephrectomy in comparison with laparoscopic nephrectomy. (2) Methods: We performed a systematic review according to the PRISMA criteria during September 2022. We included clinical trials, and cohort and case-control studies published between 2000 and 2022. This comprised studies performed in adult patients with T1 renal cancer and studies comparing robotic with open and laparoscopic partial nephrectomy. A risk of bias assessment was performed according to the Newcastle—Ottawa scale. (3) Results: We observed lower hot ischemia times in the robotic surgery groups, although at the cost of an increase in total operative time, without appreciating the differences in terms of serious surgical complications (Clavien III–V). (4) Conclusions: Robotic partial nephrectomy is a safe procedure, with a shorter learning curve than laparoscopic surgery and with all the benefits of minimally invasive surgery.

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.

Clinical outcomes of robotic-assisted laparoscopic partial nephrectomy with renal hypothermia perfusion by renal artery balloon catheter in treating patients with complex renal tumors

Objective

This study aimed to investigate the safety and efficacy of renal hypothermic perfusion by renal artery balloon catheter during robot-assisted laparoscopic partial nephrectomy (P-RALPN) for patients with complex renal tumors.

Materials and methods

We retrospectively identified 45 patients with complex renal tumors who received standard robot-assisted laparoscopic partial nephrectomy (S-RALPN) and 11 patients treated with P-RALPN from September 2017 to October 2021. Preoperative patients’ characteristics and intraoperative surgical parameters including operating time, blood loss, hospitalization, pre- and post-surgical glomerular filtration rate (GFR), and postoperative survival time were collected and compared between the two groups. The patients’ body temperature, real-time kidney temperature, and short-term renal function were analyzed in the P-RALPN group.

Results

There was no statistically significant difference on median intraoperative estimated blood loss and postoperative hospitalization between the two groups. Patients who received P-RALPN had a slightly longer operative time than those who received S-RALPN (103.1 versus 125.9; p = 0.09). In the P-RALPN group, the volume of perfusion solution was 533.2 ml (range, 255.0–750.0 ml), the median temperature of kidney was 22.6°C (range, 21.7–24.1°C) after the kidney cools down, and the median minimum intraoperative temperature of patients was 36.1°C (range 35.2–36.7°C). The ischemia time in the S-RALPN group was markedly lower than that in the P-RALPN group (21.5 versus 34.8; p < 0.01). However, the loss of GFR was much higher for the S-RALPN group after the surgery. (28.9 versus 18.4; p < 0.01). Importantly, patients had similar postoperative survival time between the two groups (p = 0.42; HR = 0.27).

Conclusion

P-RALPN is a safe and feasible surgery in the treatment of patients with complex renal tumors, which provides a new operative approach for clinicians to treat these patients.

Percutaneous Microcoil Localization of a Small, Totally Endophytic Renal Mass for Nephron-Sparing Surgery: A Case Report and Literature Review

Small, totally endophytic renal masses present a technical challenge for surgical extirpation due to poor identifiability during surgery. The method for the precise localization of totally endophytic tumours before nephron-sparing surgery could be optimized. An asymptomatic 70-year-old male presented with a right-sided, 16-mm, totally endophytic renal mass on computed tomography (CT). CT-guided percutaneous microcoil localization was carried out prior to laparoscopy to provide a direction for partial nephrectomy. During the 25 minutes of the localization procedure, the patient underwent five local CT scans, and his cumulative effective radiation dosage was 5.1 mSv. The span between localization and the start of the operation was 15 hours. The laparoscopic operation time was 105 minutes, and the ischaemia time was 25 minutes. The postoperative recovery was smooth, and no perioperative complications occurred. Pathology showed the mass to be renal clear cell carcinoma, WHO/ISUP grade 2, with a 2-mm, clear surgical margin. The patient remained free of recurrence on follow-up for eleven months. To our knowledge, this application of microcoil implantation prior to laparoscopic partial nephrectomy towards an intrarenal mass could be an early reported attempt for the localized method applied in renal surgery. The percutaneous microcoil localization of endophytic renal tumours is potentially safe and effective prior to laparoscopic partial nephrectomy.