The IRON Study: Investigation of Robot-assisted Versus Open Nephron-sparing Surgery

Incidence and predictors of ipsilateral local recurrence following partial nephrectomy

PURPOSE

Ipsilateral local recurrence (LR) after partial nephrectomy (PN) for renal cell carcinoma (RCC) may result from a metachronous tumor or PN bed recurrence. To date, literature has predominantly reported ipsilateral LRs collectively, although the pathophysiology and prognostic implications of these event may be distinct. We sought to assess variables associated with LR and evaluated associations of LR with metastasis and death from RCC.

MATERIALS AND METHODS

We identified adults undergoing PN for unilateral, sporadic, localized RCC from 2000 to 2019 using a prospectively maintained, single institution registry. LR was defined as new, enhancing tumor within/near the PN bed on MRI/CT. Cox proportional hazards models were used to create a preoperative risk score for LR and to examine the association of LR with metastasis and CSS following PN among patients with clear cell RCC.

RESULTS

In a cohort of 2,164 PNs, 106 true LRs were identified, for a 10-year incidence of 6.2%. A preoperative risk score for LR based on age, symptoms, solitary kidney, complex tumor necessitating open partial nephrectomy, and cT stage was created (c-index = 0.73). Postoperatively, positive margins, pT stage, and clear cell subtype were associated with LR. Notably, 21% (23/106) of patients with LR presented with synchronous metastases. Following LR, 5-year metastasis-free and cancer-specific survival were 64% and 71%, respectively. LR remained associated with metastasis (HR 6.25; P < 0.001) and death from RCC (HR 1.93; P = 0.03) on multivariable analysis.

CONCLUSIONS

We developed a preoperative risk score to identify patients at risk for LR following PN. LR was an independent risk factor for metastasis and death from RCC. Further study is warranted to determine whether treatment of LR improves oncologic outcomes.

Comparing robotic and open partial nephrectomy under the prism of surgical precision: a meta-analysis of the average blood loss rate as a novel variable

Exploration of surgical precision in robotic procedures is extensive, yet lacks a unified framework for comparability. This study examines tissue handling precision by comparing the per-minute blood loss rate between robotic and open partial nephrectomy. A literature search from August 2022 to June 2024 identified 43 relevant studies providing data on estimated blood loss and procedure duration. The expected values and standard errors of these variables were used to compute the per-minute blood loss rate (Q). Meta-analytical methods estimated pooled and subgroup-level mean differences, favoring robotic surgery (MDQ = - 1.043 ml/min, CI95% = [- 1.338; - 0.747]). Subgroup analyses by publication year, patient matching, referral center count, and ROBINS-I status consistently supported this advantage. Sensitivity analyses confirmed the above benefit in studies with increased accuracy in reported results (MDQ = - 0.957 ml/min, CI95% = [- 1.269; - 0.646]), low risk of bias involving matched comparisons (MDQ = - 0.563 ml/min, CI95% = [- 0.716; - 0.410]), large sample sizes and increased statistical power (MDQ = - 0.780 ml/min, CI95% = [- 1.134; - 0.425]), and multicenter analyses with patient matching (MDQ = - 0.481 ml/min, CI95% = [- 0.698; - 0.263]). The subsequent analysis of correlation between the original variables suggested a slight reduction in the robotic advantage when the latter were proportionally related. Multilevel meta-regression at both temporal and qualitative scales consistently indicated a comparative benefit of the robotic approach. Potentially, lower per-minute blood loss compared to open surgery suggests that robotic partial nephrectomy demonstrates enhanced precision in tissue handling.

Single-port vs multi-port robot-assisted partial nephrectomy: A single center propensity score-matched analysis

INTRODUCTION AND OBJECTIVES

The aim of the study is to compare key outcomes of Single-Port (SP) and Multi-Port (MP) robot-assisted partial nephrectomy (RAPN).

METHODS

A retrospective analysis was conducted on our prospectively collected database of patients who underwent SP-RAPN or MP-RAPN at our institution from January 2021 to August 2023. To adjust for potential baseline pre-operative confounders, a 1:1 propensity-score matching analysis (PSMa) was performed. The primary endpoint was to compare perioperative outcomes between the two groups. The secondary endpoint was to compare the achievement of the "Trifecta" outcome (defined as negative surgical margins, absence of high-grade complications and change in eGFR values (ΔeGFR) < 10% at 6 months follow-up) in the matched cohort.

RESULTS

After PSMa, 30 SP cases were matched 1:1 to 30 MP cases. In the matched cohort, there were no significant differences between SP and MP approaches in operative time, estimated blood loss, ischemia time, transfusions rate, intraoperative complications, postoperative complications, and positive surgical margin rates. Patients who underwent SP-RAPN had a shorter median length of stay [25 (IQR:24.0-34.5) vs 34 (IQR:30.2-48.0) hours, p < 0.003]. The Trifecta outcome was achieved in 16 (57%) of SP patients and 17 (63%) of MP patients (p = 0.8).

CONCLUSIONS

SP-RAPN can be safely implemented in a Center with an established MP-RAPN program. Despite being early in the SP-RAPN experience, key surgical outcomes are not compromised. While offering comparable perioperative and short-term functional outcomes, SP-RAPN can translate into faster recovery and shorter LOS, paving the way for outpatient robotic surgery.

Postoperative outcomes of transperitoneal versus retroperitoneal robotic partial nephrectomy: a propensity-score matched comparison focused on patient mobilization, return to bowel function, and pain

Literature meta-analyses comparing transperitoneal versus retroperitoneal approach to robotic partial nephrectomy (RPN) suggested some advantages favoring retroperitoneoscopy. Unfortunately, patient-centered data about mobilization, canalization, pain, and use of painkillers remained anecdotally reported. The present analysis aimed to compare transperitoneal versus retroperitoneal RPN focusing on such outcomes. Study data including baseline variables, perioperative, and postoperative outcomes of interest were retrieved from prospectively maintained institutional database (Jan 2018-May 2023) and compared between treatment groups (transperitoneal versus retroperitoneal). Propensity score matching was performed using the STATA command psmatch2 considering age, sex, body mass index, previous abdominal surgery, RENAL score, tumor size and location, and cT stage. The logit of propensity score was used for matching, with a 1:1 nearest neighbor algorithm, without replacement (caliper of 0.001). A total of 442 patients were included in the unmatched analysis: 330 underwent transperitoneal RPN 112 retroperitoneal RPN. After propensity score, 98 patients who underwent retroperitoneal RPN were matched with 98 patients who underwent transperitoneal RPN. Matched cohorts had comparable patients' demographics and tumor features. We found similarity between the two laparoscopic accesses in all outcomes but in blood loss, which favored retroperitoneoscopic RPN (median 150 (IQR 100-300) versus 100 (IQR 0-100) ml, p = 0.03). No differences were found in terms of time to mobilization with ambulation, return to complete bowel function, postoperative pain, but higher painkillers consumption was reported after transperitoneal RPN (p < 0.004). The present study compared the transperitoneal versus the retroperitoneal approach to RPN, confirming the similarity between the two approaches in all perioperative outcomes. Based on our findings, the choice of the surgical approach to RPN may remain something that the surgeon decides.

Surgical Phase Duration in Robot-Assisted Partial Nephrectomy: A Surgical Data Science Exploration for Clinical Relevance

(1) Background: Surgical phases form the basic building blocks for surgical skill assessment, feedback, and teaching. The phase duration itself and its correlation with clinical parameters at diagnosis have not yet been investigated. Novel commercial platforms provide phase indications but have not been assessed for accuracy yet. (2) Methods: We assessed 100 robot-assisted partial nephrectomy videos for phase durations based on previously defined proficiency metrics. We developed an annotation framework and subsequently compared our annotations to an existing commercial solution (Touch Surgery, Medtronic™). We subsequently explored clinical correlations between phase durations and parameters derived from diagnosis and treatment. (3) Results: An objective and uniform phase assessment requires precise definitions derived from an iterative revision process. A comparison to a commercial solution shows large differences in definitions across phases. BMI and the duration of renal tumor identification are positively correlated, as are tumor complexity and both tumor excision and renorrhaphy duration. (4) Conclusions: The surgical phase duration can be correlated with certain clinical outcomes. Further research should investigate whether the retrieved correlations are also clinically meaningful. This requires an increase in dataset sizes and facilitation through intelligent computer vision algorithms. Commercial platforms can facilitate this dataset expansion and help unlock the full potential, provided that the phase annotation details are disclosed.

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.

Can the Abdominal Aortic Atherosclerotic Plaque Index Predict Functional Outcomes after Robot-Assisted Partial Nephrectomy?

This study aims to evaluate the abdominal aortic atherosclerotic plaque index (API)'s predictive role in patients with pre-operatively or post-operatively developed chronic kidney disease (CKD) treated with robot-assisted partial nephrectomy (RAPN) for renal cell carcinoma (RCC). One hundred and eighty-three patients (134 with no pre- and post-operative CKD (no CKD) and 49 with persistent or post-operative CKD development (post-op CKD)) who underwent RAPN between January 2019 and January 2022 were deemed eligible for the analysis. The API was calculated using dedicated software by assessing the ratio between the CT scan atherosclerotic plaque volume and the abdominal aortic volume. The ROC regression model demonstrated the influence of API on CKD development, with an increasing effect according to its value (coefficient 0.13; 95% CI 0.04-0.23; p = 0.006). The Model 1 multivariable analysis of the predictors of post-op CKD found that the following are independently associated with post-op CKD: Charlson Comorbidity Index (OR 1.31; p = 0.01), last follow-up (FU) Δ%eGFR (OR 0.95; p < 0.01), and API ≥ 10 (OR 25.4; p = 0.01). Model 2 showed API ≥ 10 as the only factor associated with CKD development (OR 25.2; p = 0.04). The median follow-up was 22 months. Our results demonstrate API to be a strong predictor of post-operative CKD, allowing the surgeon to tailor the best treatment for each patient, especially in those who might be at higher risk of CKD.

Long-Term Oncological and Functional Outcomes after Laparoscopic Partial Nephrectomy with Hyperselective Embolization of Tumor Vessels in a Hybrid Operating Room

Laparoscopic partial nephrectomy (LPN) after hyperselective embolization of tumor vessels (HETV) in a hybrid operating room (HOR) that combines traditional surgical equipment with advanced imaging technology, is a non-clamping surgical approach to treat localized kidney tumors that has shown promising short-term results. The aim of this study was to evaluate the long-term oncological and functional outcomes of this procedure. All consecutive patients treated for a localized kidney tumor by LPN after HETV between May 2015 and October 2022 in a single academic institution were included in the study. Clinical, pathological and biological data were collected prospectively in the uroCCR database. We evaluated intraoperative data, postoperative complications, surgical margin and modification of renal function after surgery. We included 245 patients. The median tumor size was 3.2 (2.5-4.4) cm. The R.E.N.A.L. complexity was low, medium and high for 104 (43.5%), 109 (45.6%) and 26 (10.9%) patients, respectively. Median LPN time was 75 (65-100) min and median blood loss was 100 (50-300) mL. Surgical postoperative complications occurred in 56 (22.9%) patients with 17 (5.7%) major complications. The median Glomerular Function Rate variation at 6 months was -7.5 (-15--2) mL/min. Malignant tumors were present in 211 (86.1%) patients, and 12 (4.9%) patients had positive surgical margins. After a median follow-up of 27 (8-49) months, 20 (8.2%) patients had a tumor recurrence and 4 (1.6%) died from cancer. At 5 years, disease free survival, cancer specific survival and overall survival rates were 84%, 96.8% and 88.3%, respectively. Performing LPN after HETV in a HOR is a safe and efficient non-clamping approach to treat localized kidney tumors.