Long-term oncological outcomes after robotic partial nephrectomy for renal cell carcinoma: a prospective multicentre study

Outcomes and Techniques of Robotic-Assisted Partial Nephrectomy (RAPN) for Renal Hilar Masses: A Comprehensive Systematic Review

Background: Robot-assisted partial nephrectomy (RAPN) is increasingly being employed in the management of renal cell carcinoma (RCC) and it is expanding in the field of complex renal tumors. The aim of this systematic review was to consolidate and assess the results of RAPN when dealing with entirely central hilar masses and to examine the various methods used to address the surgical difficulties associated with them. Methods: A thorough literature search in September 2023 across various databases focused on RAPN for renal hilar masses, adhering to PRISMA guidelines. The primary goal was to evaluate RAPN's surgical and functional outcomes, with a secondary aim of examining different surgical techniques. Out of 1250 records, 13 full-text manuscripts were reviewed. Results: Evidence is growing in favor of RAPN for renal hilar masses. Despite a predominance of retrospective studies and a lack of long-term data, RAPN shows positive surgical outcomes and preserves renal function without compromising cancer treatment effectiveness. Innovative suturing and clamping methods are emerging in surgical management. Conclusions: RAPN is a promising technique for managing renal hilar masses in RCC, offering effective surgical outcomes and renal function preservation. The study highlights the need for more long-term data and prospective studies to further validate these findings.

Predictive factors for pentafecta achievement in robot-assisted partial nephrectomy for intermediate highly complex RENAL tumors (RENAL score ≥ 7)

OBJECTIVES

To investigate the predictive factors for pentafecta achievement of robot-assisted partial nephrectomy (RAPN) for intermediate highly complex renal tumors (RENAL score ≥ 7).

METHODS

We retrospectively analyzed the data of 247 patients with renal tumors with a RENAL score ≥ 7 who underwent RAPN. Baseline characteristics and perioperative outcomes were compared between the pentafecta achieved group and the unachieved group. A multivariable logistic regression model was used to identify the predictive factors for pentafecta achievement for cT1 renal tumors with a RENAL score ≥ 7.

RESULTS

Of the 247 patients, 75 (30.3%) patients were in the achieved group and 172 (69.7%) patients were in the unachieved group. The median warm ischemia time and total operation time were 18 min versus 23 min (p < 0.001) and 179 min versus 201 min (p < 0.001) in the achieved and unachieved groups, respectively. In the unachieved group, six patients (3.4%) had major perioperative complications (Clavien-Dindo classification system ≥3). The median preservation rates of estimated GFR at the 1-year postoperative period were 96.5% versus 83.0% (p < 0.001) in the achieved and unachieved groups. Multivariable logistic regression models revealed that age and tumor size were independent predictive factors for pentafecta achievement for cT1 renal tumors with a RENAL score ≥ 7. There were no significant differences in cancer-free survival between the two groups (p = 0.456).

CONCLUSION

Age and tumor size were independent predictive factors for pentafecta achievement, although there was no difference in oncological outcomes between the pentafecta achieved group and the unachieved group in RAPN for cT1 renal tumors with a RENAL score ≥ 7.

Does tumor rupture during robot-assisted partial nephrectomy have an impact on mid-term tumor recurrences?

BACKGROUND

Intraoperative kidney tumor rupture (TR) can occur during robot-assisted partial nephrectomy (RAPN) in daily clinical practice, but there are no solid guidelines on the management and implications of it. The purpose of the study was to investigate the impact of TR on tumor recurrences, what a surgeon should do if this adverse event occurs, and how to avoid it.

PATIENTS AND METHODS

We retrospectively analyzed the first 100 patients who underwent RAPN at University Medical Centre Ljubljana, between 2018 and 2021. Patients were stratified into 2 groups (TR and no-TR) and were compared according to patient, tumor, pathologic, perioperative and postoperative characteristics and tumor recurrences, using the Mann-Whitney U test and chi-squared test.

RESULTS

Of the 100 patients, 14 had TR (14%); this occurred in tumors with higher RENAL nephrometry scores (P = 0.028) and mostly with papillary renal cell carcinomas (P = 0.043). Median warm ischemia time was longer for the TR group (22 vs. 15 min, P = 0.026). In terms of studied outcomes, there were no cases of local or distant recurrence after a median observation time of 39 months (interquartile range, 31-47 months) in both groups. We observed positive surgical margins on the final oncologic report in one case in the no-TR group.

CONCLUSIONS

Tumor rupture during RAPN seems to be of no mid-term oncologic importance. According to presented results, we would recommend surgeons to proceed with tumor resection if this event occurs and abstain from conversion to radical nephrectomy or open partial nephrectomy. However, more similar cases should be studied to make more solid conclusions.

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.

Late complications and 5 years outcomes of robotic partial nephrectomy in France: prospective assessment in the French Kidney Cancer Research Network (UroCCR 10)

PURPOSE

To describe the practice of robotic-assisted partial nephrectomy (RAPN) in France and prospectively assess the late complications and long-term outcomes.

METHODS

Prospective, multicenter (n = 16), observational study including all patients diagnosed with a renal tumor who underwent RAPN. Preoperative, intraoperative, postoperative, and follow-up data were collected and stored in the French research network for kidney cancer database (UroCCR). Patients were included over a period of 12 months, then followed for 5 years.

RESULTS

In total, 466 patients were included, representing 472 RAPN. The mean tumor size was 3.4 ± 1.7 cm, most of moderate complexity (median PADUA and RENAL scores of 8 [7-10] and 7 [5-9]). Indication for nephron-sparing surgery was relative in 7.1% of cases and imperative in 11.8%. Intraoperative complications occurred in 6.8% of patients and 4.2% of RAPN had to be converted to open surgery. Severe postoperative complications were experienced in 2.3% of patients and late complications in 48 patients (10.3%), mostly within the first 3 months and mainly comprising vascular, infectious, or parietal complications. At 5 years, 29 patients (6.2%) had chronic kidney disease upstaging, 21 (4.5%) were diagnosed with local recurrence, eight (1.7%) with contralateral recurrence, 25 (5.4%) with metastatic progression, and 10 (2.1%) died of the disease.

CONCLUSION

Our results reflect the contemporary practice of French expert centers and is, to our knowledge, the first to provide prospective data on late complications associated with RAPN. We have shown that RAPN provides good functional and oncologic outcomes while limiting short- and long-term morbidity.

TRIAL REGISTRATION

NCT03292549.

Cost-effectiveness of robotic-assisted surgery vs open surgery in the context of partial nephrectomy for small kidney tumors

To evaluate the cost-effectiveness of robotic-assisted surgery compared to open surgery in the context of partial nephrectomy for small kidney tumor management. This is a retrospective study using data from 395 patients operated on by either robot-assisted surgery (RAPN) or by open partial nephrectomy (OPN); one hospital performed RAPN exclusively and the second hospital, OPN exclusively. Cost-effectiveness analysis was conducted from the perspective of the National Health Insurance System (NHIS) by considering the costs of the initial hospital stay and the cost of complications. Clinical outcome was defined by the avoidance of major complications during the 12 months postoperatively. Major complications were absent in 82% of patients in the OPN group and 93% of patients in the RAPN group, with 11% in favor of robotic assistance (p < 0.001). The average cost per patient, including the costs of complications, were, respectively, 9637 € and 8305 € for the OPN and RAPN groups. Robotic assistance was associated with a 1332 € lower cost (p < 0.001). The incremental cost-effectiveness ratio (ICER) is estimated at - 12,039 €. From the perspective of the public payer, robotic assistance was associated with a lower rate of postoperative complications and a lower average cost per patient. Robotic-assisted surgery was an efficient alternative to open surgery in partial nephrectomy. Trial registration number: NCT05089006 (October 22, 2021).

Robot-assisted partial nephrectomy: Can retroperitoneal approach suit for renal tumors of all locations?-A large retrospective cohort study

BACKGROUND

This study aimed to explore the appropriate location of renal tumors for retroperitoneal approach.

MATERIALS AND METHODS

We retrospectively analyzed 1040 patients with renal tumor who were treated at our institution from Janurary 2015 to June 2020 and had underwent retroperitoneal robotic assisted-laparoscopic partial nephrectomy (rRAPN). Clinical features and postoperative outcomes were evaluated.

RESULTS

Patients with incomplete data were excluded, and we included 896 patients in total. The median tumor size was 3.0 (range: 0.8-10.0) cm. The median RENAL Nephrometry Score was 7 (range: 4-11), and the median PADUA Nephrometry Score was 8 (range: 6-14). The median surgical time was 120 min, and the median warm ischemia time was 18 min. The median estimated blood loss was 50 ml. The follow-up time was 20.2 (range: 12-69) months. The mean change of eGFR 1 year after operation was 14.6% ± 19.0% compared with preoperative estimated glomerular filtration rate (eGFR). When compared the tumor at different locations, as superior or inferior pole, anterior of posterior face of kidney, there were no significant differences of intra- and post-operative outcomes such as surgical time, warm ischemia time, estimated blood loss, removal time of drainage tube and catheter, postoperative feeding time and hospital stay, and changes of eGFR one year after surgery. We also compared tumors at special locations as endophytic or exophytic, anterior of posterior hilus of kidney, there were no significant differences in surgical time, warm ischemia time, estimated blood loss and changes of eGFR. There was no significant difference in intraoperative features and postoperative outcomes when tumor larger than 4 cm was located at different positions of kidney. Though the surgical time was longer when BMI ≥ 28 (132.6 min vs. 122.5 min, p = 0.004), no significant differences were observed in warm ischemia time, estimated blood loss, changes in eGFR. Twenty-seven patients (3.0%) had tumor progression, including 8 (0.9%) recurrence, 19 (2.1%) metastasis, and 9 (1.0%) death.

CONCLUSION

Retroperitoneal approach for RAPN has confirmed acceptable intra- and postoperative outcomes and suits for renal tumors of all different locations. Large tumor size and obesity are not contraindications for rRAPN.

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.

Robot-assisted partial nephrectomy with minimum follow-up of 5 years: A multi-center prospective study in Japan

OBJECTIVES

Robot-assisted partial nephrectomy is widely performed for small renal masses, achieving excellent perioperative and intermediate oncological outcomes. However, long-term oncological, functional, and quality of life outcomes after robot-assisted partial nephrectomy remain unclear. In this study, we aimed to evaluate quality of life at 1 year and oncological and functional outcomes of robot-assisted partial nephrectomy after a minimum follow-up of 5 years.

METHODS

Personal, perioperative, postoperative, functional, oncological, and quality of life data were evaluated. The EQ-5D-5L tool, which incorporates health profiles and a EuroQol Visual Analog Scale, was used to assess quality of life preoperatively and 365 days postoperatively. Regarding oncological and functional outcomes, overall survival, recurrence-free survival, and changes in estimated glomerular filtration rate were calculated.

RESULTS

There were few changes in levels between the two time points for all EQ-5D dimensions. The mean change in EQ-5D-5L was 0.020 (95% confidence interval 0.006-0.033, P = 0.006), and in EuroQol Visual Analog Scale score 4.60 (95% confidence interval 2.17-7.02, P = 0.0003). Overall and recurrence-free survival 5 years after robot-assisted partial nephrectomy were 97.9% and 92.8%, respectively. After an early postoperative decrease, the estimated glomerular filtration rate remained stable over time.

CONCLUSIONS

Robot-assisted partial nephrectomy in patients with a T1 renal tumor is safe, feasible, and effective from the perspective of quality of life and survival, even after 5 years. When making treatment decisions, perioperative and quality of life outcomes should be considered together with long-term oncological outcomes.

Robot-assisted partial nephrectomy for high-complexity tumors (PADUA score ≥10): Perioperative, long-term functional and oncologic outcomes

OBJECTIVES

To evaluate the safety and efficacy, and long-term functional and oncologic outcomes of robot-assisted partial nephrectomy in high-complexity tumors.

METHODS

Data of 155 patients with a high-complexity tumor (PADUA score ≥10) were reviewed. Trifecta achievement, intra-, perioperative, functional, and oncologic outcomes were analyzed and compared between patients with increasing complexity.

RESULTS

Of the 155 patients, 65 (41.9%) patients had a PADUA score of 10, 55 (35.5%) had a PADUA score of 11, and 35 (22.6%) had a PADUA score of 12-13, respectively. The median (interquartile range) operative time, warm ischemia time and estimated blood loss were 150 min (112-186 min), 26 min (23-32 min) and 250 mL (100-500 mL), respectively. Postoperatively, complications occurred in 25 (16.1%) patients, and positive surgical margins in 15 (10.5%) patients. Trifecta was achieved in 67 (43.2%) patients. At a median follow-up period of 58 months, the median estimated glomerular filtration rate preservation was 87% (78-110), and 12 (7.7%) patients developed new-onset chronic kidney disease. Recurrence-free survival and overall survival rates were 93.6% and 96.7%, respectively. Positive surgical margins were statistically different between the groups of PADUA score 10, 11 and 12-13 (P = 0.017), whereas functional and oncologic outcomes were similar. In multivariate logistic regression analysis, increasing tumor size (odds ratio 1.48, 95% confidence interval 1.21-1.87; P < 0.001) and the American Society of Anesthesiologists score 2/3 (odds ratio 0.48, 95% confidence interval 0.24-0.96; P = 0.041) were independent predictors of trifecta failure.

CONCLUSIONS

Robot-assisted partial nephrectomy is a safe and effective treatment for high-complexity tumors providing excellent long-term functional and oncologic outcomes.

Utilization of a three-dimensional printed kidney model for favorable TRIFECTA achievement in early experience of robot-assisted partial nephrectomy

Background

This retrospective study aimed to investigate whether a three-dimensional (3D) model would improve the achievement of TRIFECTA, which was defined as the absence of perioperative complications and positive surgical margins and a warm ischemia time of <25 minutes, during robot-assisted partial nephrectomy (RAPN).

Methods

Prior to RAPN, a 3D-square type kidney model was prepared and used for all RAPN procedures in patients with T1a renal cell carcinoma (RCC) treated at a single center between March 2016 and April 2019. All RAPN procedures were performed by a single surgeon.

Results

The study included 50 patients, of whom 22, 24, and 4 had low-, intermediate-, and high-risk R.E.N.A.L Nephrometry scores, respectively. The TRIFECTA achievement rate was 86.0%, and transfusion or conversion to radical nephrectomy was not required in any of the patients. Only one Clavien-Dindo grade 3 complication was reported—a pseudoaneurysm that required embolism. The TRIFECTA achievement rate was independent of the R.E.N.A.L Nephrometry scores and the surgeon’s experience level (25 cases each of early and advanced experience).

Conclusions

The 3D model contributed to the achievement of TRIFECTA during RAPN performed by a less-experienced surgeon. These findings should be further evaluated in studies involving a larger number of cases and surgeons.

Robot-assisted partial nephrectomy: 7-year outcomes

BACKGROUND

The role of robot-assisted partial nephrectomy (RAPN) in the management of renal masses has exponentially grown over the past 10 years. Nevertheless, data on long term outcomes of the procedure remains limited. Herein we report oncological and functional outcomes of patients who underwent RAPN for a malignant mass with a median follow-up of 7 years, the longest follow-up to date.

METHODS

A retrospective analysis of an international multicenter database was performed. All consecutive patients undergoing surgery between 2009 and 2013 with a minimum of 3-year follow-up and complete data on renal function were included. Demographics, surgical and perioperative outcomes were analyzed. Overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS) were evaluated using Kaplan-Meier analysis.

RESULTS

Overall, our study cohort was composed of eighty-five patients with a median follow-up of 88 months. Median clinical tumor size was 3 cm, with mostly (74.1%) clinical stage T1a, and median RENAL score 6. Final histopathologic analysis revealed clear cell RCC in 76.5% of cases. PSM was present in seven patients (8.2%). Eleven overall deaths (12.9%) occurred in the cohort during the follow-up period. Two of these (2.33%) were attributed to metastatic RCC. The OS, CSS, and DFS rates were 91.7%, 97.7%, and 91.7% at 84 months, respectively. Regarding the renal functional outcomes, seventeen patients (20.1%) presented a CKD upstaging in our cohort.

CONCLUSIONS

Our findings show excellent 7-year oncologic and functional outcomes of the procedure, which duplicate those achieved in historical series of open and laparoscopic surgery.

Long-term oncologic outcomes of positive surgical margins following robot-assisted partial nephrectomy

Background

Previous reports on positive surgical margin (PSM) after robot-assisted partial nephrectomy (RAPN) have reached inconsistent conclusions as to the impact of a PSM on oncologic outcomes. We sought to determine the effect of PSM on long-term cancer recurrence and survival outcomes.

Methods

We queried our renal oncology database for patients having undergone RAPN and compared recurrence-free survival (RFS) and overall survival (OS) between patients with PSM and negative surgical margin (NSM). Kaplan-Meier analysis was also performed for RFS and OS for PSM versus NSM.

Results

Of the 432 patients who underwent RAPN we identified 29 (6.7%) patients with PSM and 403 (93.3%) patients with NSM. Median follow-up for the overall cohort was 45.1 months. Three of the 29 patients with PSM and fourteen of the 403 patients with NSM had disease recurrence (P=0.09). RFS at 24, 48, and 72 months was 95.8%, 90%, and 85.5% for patients with NSM and 96.6%, 86.6%, and 80.4% for patients with PSM, respectively (log-rank P value =0.382). OS at 24, 48, and 72 months was 98%, 93.1%, and 89.7% for patients with NSM and 96.3%, 91.2%, and 85.2% for patients with PSM, respectively (log-rank P value =0.584).

Conclusions

While PSM are relatively uncommon, their presence still serves as a potential risk factor for worse oncologic outcomes. In instances of PSM, immediate secondary intervention is most likely unnecessary and more attentive long-term clinical follow-up, especially in patients with high-risk features, may be more advisable.

Local Recurrence Following Resection of Intermediate-High Risk Nonmetastatic Renal Cell Carcinoma: An Anatomical Classification and Analysis of the ASSURE (ECOG-ACRIN E2805) Adjuvant Trial

PURPOSE

We describe what is to our knowledge a novel classification system for local recurrence after surgery of renal cell carcinoma. We assessed its prognostic implications using prospective, randomized controlled data.

MATERIALS AND METHODS

We queried the ASSURE (Sunitinib Malate or Sorafenib Tosylate in Treating Patients With Kidney Cancer That Was Removed By Surgery) (ECOG-ACRIN [Eastern Cooperative Oncology Group-American College of Radiology Imaging Network] E2805) trial data for patients with fully resected, intermediate-high risk, nonmetastatic renal cell carcinoma with local recurrence. We used certain definitions, including type I-single recurrence in a remnant kidney or ipsilateral renal fossa, type II-single recurrence in the ipsilateral vasculature, the ipsilateral adrenal gland or a lymph node, type III-single recurrence in other intra-abdominal soft tissues or organs and type IV-any combination of types I-III or multiple recurrences of a single type. Multivariable logistic regression and the log rank test were performed to identify clinicopathological predictors and compare survival, respectively.

RESULTS

Of the 1,943 patients 300 (15.4%) had local recurrence, which was type I, II, III and IV in 66 (22.0%), 97 (32.3%), 87 (29.0%) and 50 (16.7%), respectively. Surgical modality (minimally invasive vs open) and type of surgery (partial vs radical) did not predict any local recurrence. Five-year cancer specific survival and overall survival were worse in patients with type IV recurrence (each p <0.001). There was no difference in survival among patients with types I to III recurrence.

CONCLUSIONS

In patients with intermediate-high risk nonmetastatic renal cell carcinoma local recurrence appears to be a function of biology more than of surgical modality or surgery type. The prognosis for solitary intra-abdominal local recurrences appear similar regardless of location (types I-III). Local recurrences involving multiple sites and/or subdivisions are associated with worse survival (type IV).

Low Rate of Cancer Events After Partial Nephrectomy for Renal Cell Carcinoma: Clinicopathologic Analysis of 1994 Cases with Emphasis on Definition of "Recurrence"

BACKGROUND

Systematic pathology reviews in patients who experienced a clinical "recurrence" after partial nephrectomy for renal cell carcinoma (RCC) are anecdotal; therefore, definitions of "recurrence" varies considerably. We aimed to better define local recurrence by re-evaluation of surgical specimens of patients who experienced "recurrences" after partial nephrectomy at our institution.

MATERIALS AND METHODS

Retrospective analysis of our institutional partial nephrectomy data set was performed. Patients who were clinically diagnosed with a local recurrence during the oncological follow-up after primary intervention for RCC were considered (January 2007 to December 2017, institutional review board number 5065, 15-1593). Re-evaluation of specimens coming from either primary treatment or management of the diagnosed recurrent disease was performed by 2 dedicated urologic pathologists. According to the findings of the pathology review, patients were assigned to 3 groups of disease event: (1) local recurrence of RCC; (2) new occurrence of RCC; and (3) micrometastatic RCC. Patient demographic characteristics, tumor pathological characteristics, oncological outcomes, disease treatment, and follow-up were reported for each patient. Cancer-specific survival was compared using the Kaplan-Meier method.

RESULTS

Of 1994 cases recorded in the institutional database, data on 30 patients who were clinically diagnosed with a local recurrence were extracted. After pathology review, 9 patients were found who truly developed a local recurrence (group 1). Positive surgical margin status was poorly related to the likelihood of a true local recurrence as defined herein. Twelve patients were assessed with a new occurrence of RCC (group 2). Nine were diagnosed with micrometastatic RCC (group 3). With comparable follow-up lengths among the groups (39 [interquartile range (IQR), 32-45] versus 51.5 [IQR, 35-90.5] versus 42 [IQR, 13-65], group 1 versus 2 versus 3, respectively; P = .4), patients classified in group 1 and 3 had comparable cancer-specific survival (P = .5). Conversely, patients in group 2 were less likely to die of disease compared with group 1 and 3 patients (P = .02).

CONCLUSION

Careful pathologic classification of RCC disease events after partial nephrectomy has important prognostic implications and allows more precise study of the clinical significance of margin status.

Simplified robot-assisted partial nephrectomy: step-by-step technique and perioperative outcomes

Controversies have been raised and still exist regarding several technical aspects of robot-assisted partial nephrectomy (RAPN). While the "perfect RAPN" has still to be determined, we aimed to report a simplified technique of RAPN in a step-by-step fashion and the perioperative outcomes of a single-center series. A simplified technique of RAPN was developed, refined and standardized over the past 7 years in an academic department of urology to make it as safe and as reproducible as possible, the main goal being to make it an "easy to learn" technique for fellows. This technique is presented in 12 key steps. The patients' characteristics and perioperative outcomes were prospectively collected and are reported herein. Since the first case performed in our department in 2010, 406 patients have undergone RAPN with a standardized and stable simplified technique after the first 30 cases, involving several key steps including systematic use of the transperitoneal approach, minimal visceral mobilization of the colon, systematic psoas exposure and ureter identification, minimal dissection of the perinephric fat, arterial clamping with early unclamping, no use of hemostatic agents or drain. The majority of RAPN were performed by surgeons with either low experience (i.e., < 20 procedures; 46.3%) or intermediate experience (i.e., 20-50 procedures; 17.2%). The mean warm ischemia time was 15.3 min. Conversions to an open approach and to radical nephrectomy were required in 14 (3.5%) and 21 (5.2%) cases, respectively. From 132 patients who experienced post-operative complications (32.5%), 47 experienced a major complication (11.6%). The positive surgical margin rate was 5.6%. The simplified technique of RAPN was feasible and reproducible with satisfactory perioperative outcomes. Most of the key steps have been assessed through single-center and multicenter clinical studies.