Comparison of perioperative outcomes following transperitoneal versus retroperitoneal robot-assisted partial nephrectomy: a propensity-matched analysis of VCQI database.

OBJECTIVE: To compare perioperative outcomes following retroperitoneal robot-assisted partial nephrectomy (RPRAPN) and transperitoneal robot-assisted partial nephrectomy (TPRAPN). METHODS: With this Vattikuti Collective Quality Initiative (VCQI) database, study propensity scores were calculated according to the surgical access (TPRAPN and RPRAPN) for the following independent variables, i.e., age, sex, side of the surgery, RENAL nephrometry scores (RNS), estimated glomerular filtration rate (eGFR) and serum creatinine. The study's primary outcome was the comparison of trifecta between the two groups. RESULTS: In this study, 309 patients who underwent RPRAPN were matched with 309 patients who underwent TPRAPN. The two groups matched well for age, sex, tumor side, polar location of the tumor, RNS, preoperative creatinine and eGFR. Operative time and warm ischemia time were significantly shorter with RPRAPN. Intraoperative blood loss and need for blood transfusion were lower with RPRAPN. There was a significantly higher number of intraoperative complications with RPRAPN. However, there was no difference in the two groups for postoperative complications. Trifecta outcomes were better with RPRAPN (70.2% vs. 53%, p < 0.0001) compared to TPRAPN. We noted no significant change in overall results when controlled for tumor location (anteriorly or posteriorly). The surgical approach, tumor size and RNS were identified as independent predictors of trifecta on multivariate analysis. CONCLUSION: RPRAPN is associated with superior perioperative outcomes in well-selected patients compared to TPRAPN. However, the data for the retroperitoneal approach were contributed by a few centers with greater experience with this technique, thus limiting the generalizability of the results of this study.

Perioperative outcomes following robot-assisted partial nephrectomy in elderly patients.

OBJECTIVE: To compare perioperative outcomes following robot-assisted partial nephrectomy (RAPN) in patients with age ≥ 70 years to age < 70 years. METHODS: Using Vattikuti Collective quality initiative (VCQI) database for RAPN we compared perioperative outcomes following RAPN between the two age groups. Primary outcome of the study was to compare trifecta outcomes between the two groups. Propensity matching using nearest neighbourhood method was performed with trifecta as primary outcome for sex, body mass index (BMI), solitary kidney, tumor size and Renal nephrometery score (RNS). RESULTS: Group A (age ≥ 70 years) included 461 patients whereas group B included 1932 patients. Before matching the two groups were statistically different for RNS and solitary kidney rates. After propensity matching, the two groups were comparable for baselines characteristics such as BMI, tumor size, clinical symptoms, tumor side, face of tumor, solitary kidney and tumor complexity. Among the perioperative outcome parameters there was no difference between two groups for operative time, blood loss, intraoperative transfusion, intraoperative complications, need for radical nephrectomy, positive margins and trifecta rates. Warm ischemia time was significantly longer in the younger age group (18.1 min vs. 16.3 min, p = 0.003). Perioperative complications were significantly higher in the older age group (11.8% vs. 7.7%, p = 0.041). However, there was no difference between the two groups for major complications. CONCLUSION: RAPN in well-selected elderly patients is associated with comparable trifecta outcomes with acceptable perioperative morbidity.

Perioperative outcomes following robot-assisted partial nephrectomy for complex renal masses: A Vattikuti Collective Quality Initiative database study.

Introduction: Outcomes of robot-assisted partial nephrectomy (RAPN) depend on tumor complexity, surgeon experience and patient profile among other variables. We aimed to study the perioperative outcomes of RAPN for patients with complex renal masses using the Vattikuti Collective Quality Initiative (VCQI) database that allowed evaluation of multinational data. Methods: From the VCQI, we extracted data for all the patients who underwent RAPN with preoperative aspects and dimensions used for an anatomical (PADUA) score of ≥10. Multivariate logistic regression was conducted to ascertain predictors of trifecta (absence of complications, negative surgical margins, and warm ischemia times [WIT] <25 min or zero ischemia) outcomes. Results: Of 3,801 patients, 514 with PADUA scores ≥10 were included. The median operative time, WIT, and blood loss were 173 (range 45-546) min, 21 (range 0-55) min, and 150 (range 50-3500) ml, respectively. Intraoperative complications and blood transfusions were reported in 2.1% and 6%, respectively. In 8.8% of the patients, postoperative complications were noted, and surgical margins were positive in 10.3% of the patients. Trifecta could be achieved in 60.7% of patients. Clinical tumor size, duration of surgery, WIT, and complication rates were significantly higher in the group with a high (12 or 13) PADUA score while the trifecta was significantly lower in this group (48.4%). On multivariate analysis, surgical approach (retroperitoneal vs. transperitoneal) and high PADUA score (12/13) were identified as predictors of the trifecta outcomes. Conclusion: RAPN may be a reasonable surgical option for patients with complex renal masses with acceptable perioperative outcomes.

Robotic partial nephrectomy vs minimally invasive radical nephrectomy for clinical T2a renal mass: a propensity score-matched comparison from the ROSULA (Robotic Surgery for Large Renal Mass) Collaborative Group.

OBJECTIVE: To compare outcomes of minimally invasive radical nephrectomy (MIS-RN) and robot-assisted partial nephrectomy (RAPN) in clinical T2a renal mass (cT2aRM). PATIENTS AND METHODS: Retrospective, multicentre, propensity score-matched (PSM) comparison of RAPN and MIS-RN for cT2aRM (T2aN0M0). Cohorts were PSM for age, sex, body mass index, American Society of Anesthesiologists (ASA) class, clinical tumour size, and R.E.N.A.L. score using a 2:1 ratio for RN:PN. The primary outcome was disease-free survival (DFS). Secondary outcomes included overall survival (OS), complication rates, and de novo estimated glomerular filtration rate (eGFR) <45 mL/min/1.73 m2 . Multivariable (MVA) and Kaplan-Meier survival analyses (KMSA) were conducted. RESULTS: In all, 648 patients (216 RAPN/432 MIS-RN) were matched. There were no significant differences in intraoperative complications (P = 0.478), Clavien-Dindo Grade ≥III complications (P = 0.063), and re-admissions (P = 0.238). The MVA revealed high ASA class (hazard ratio [HR] 2.7, P = 0.044) and sarcomatoid (HR 5.3, P = 0.001), but not surgery type (P = 0.601) to be associated with all-cause mortality. Increasing R.E.N.A.L. score (HR 1.31, P = 0.037), high tumour grade (HR 2.5, P = 0.043), and sarcomatoid (HR 2.8, P = 0.02) were associated with recurrence, but not surgery (P = 0.555). Increasing age (HR 1.1, P < 0.001) and RN (HR 3.9, P < 0.001) were predictors of de novo eGFR of <45 mL/min/1.73 m2 . Comparing RAPN and MIS-RN, KMSA revealed no significant differences for 5-year OS (76.3% vs 88.0%, P = 0.221) and 5-year DFS (78.6% vs 85.3%, P = 0.630) for pT2 RCC, and no differences for 3-year OS (P = 0.351) and 3-year DFS (P = 0.117) for pT3a upstaged RCC. The 5-year freedom from de novo eGFR of <45 mL/min/1.73 m2 was 91.6% for RAPN vs 68.9% for MIS-RN (P < 0.001). CONCLUSIONS: RAPN had similar oncological outcomes and morbidity profile as MIS-RN, while conferring functional benefit. RAPN may be considered as a first-line option for cT2aRM.

'Trifecta' outcomes of robot-assisted partial nephrectomy in solitary kidney: a Vattikuti Collective Quality Initiative (VCQI) database analysis.

OBJECTIVES: To analyse the outcomes of robot-assisted partial nephrectomy (RAPN) in patients with a solitary kidney in a large multi-institutional database. PATIENTS AND METHODS: In all, 2755 patients in the Vattikuti Collective Quality Initiative database underwent RAPN by 22 surgeons at 14 centres in nine countries. Of these patients, 74 underwent RAPN with a solitary kidney between 2007 and 2016. We retrospectively analysed the functional and oncological outcomes of these 74 patients. A 'trifecta' of outcomes was assessed, with trifecta defined as a warm ischaemia time (WIT) of <20 min, negative surgical margins, and no complications intraoperatively or within 3 months of RAPN. RESULTS: All 74 patients underwent RAPN successfully with one conversion to radical nephrectomy. The median (interquartile range [IQR]) operative time was 180 (142-230) min. Early unclamping was used in 11 (14.9%) patients and zero ischaemia was used in 12 (16.2%). Trifecta outcomes were achieved in 38 of 66 patients (57.6%). The median (IQR) WIT was 15.5 (8.75-20.0) min for the entire cohort. The overall complication rate was 24.1% and the rate of Clavien-Dindo grade ≤II complications was 16.3%. Positive surgical margins were present in four cases (5.4%). The median (IQR) follow-up was 10.5 (2.12-24.0) months. The median drop in estimated glomerular filtration rate at 3 months was 7.0 mL/min/1.72 m2 (11.01%). CONCLUSION: Our findings suggest that RAPN is a safe and effective treatment option for select renal tumours in solitary kidneys in terms of a trifecta of negative surgical margins, WIT of <20 min, and low operative and perioperative morbidity.

Correction to: Robot-assisted laparoscopic pyeloplasty: a single-centre experience.

In the original version of this article, Oussama Elhage's name was spelled incorrectly. It is correct as displayed above.

Robot-assisted laparoscopic pyeloplasty: a single-centre experience.

BACKGROUND: Ureteropelvic junction obstruction (UPJO) is characterised by an obstruction compromising the passage of urine from the renal pelvis into the ureter, and can be corrected by Robot-Assisted Laparoscopic Pyeloplasty (RALP). We aimed to evaluate the surgical outcomes of RALP, and examine the rates of true pain resolution following the procedure. METHODS: We retrospectively explored the records of all patients who underwent RALP between April 2005 and January 2017. Measures of success were defined as the prevention of deterioration in split renal function and resolution of obstruction, and the resolution or improvement in subjective pain levels. RESULTS: 83 patients were included in this series. Mean patient age was 40.8 years. 38 patients had a left sided RALP, whilst 45 underwent RALP on the right. Crossing vessels were identified in 53.0% of patients. Mean operative time was 148.0 min. 68 patients had pain as their presenting feature. Following RALP, the pain resolved in 69.2% (n = 47), improved in 26.5% (n = 18), and remained the same in 4.4% (n = 3). 11.8% (n = 8) of patients required referral to other specialities for pain management. Success from a radiological perspective of cleared obstruction and arrest of deteriorating renal function was 97.6%. CONCLUSIONS: Our individual outcomes demonstrate a high success rate regarding resolution of obstruction and preventing deterioration in renal function. We also report that a number of patients, who despite meeting the radiological criteria to undergo RALP, had alternate underlying causes for their pain symptoms. For this reason, we propose that the primary measure of success for RALP should be based on renal function and radiological outcomes, rather than the outcomes relating to pain. Both surgeons and patients should be aware that whilst RALP is a highly successful procedure, persistence of pain may be due to overlapping clinical conditions which can be managed by a multidisciplinary approach.

PADUA and R.E.N.A.L. nephrometry scores correlate with perioperative outcomes of robot-assisted partial nephrectomy: analysis of the Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database.

OBJECTIVES: To evaluate and compare the correlations between Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) and R.E.N.A.L. [Radius (tumour size as maximal diameter), Exophytic/endophytic properties of the tumour, Nearness of tumour deepest portion to the collecting system or sinus, Anterior (a)/posterior (p) descriptor and the Location relative to the polar line] nephrometry scores and perioperative outcomes and postoperative complications in a multicentre, international series of patients undergoing robot-assisted partial nephrectomy (RAPN) for masses suspicious for renal cell carcinoma (RCC). PATIENTS AND METHODS: We retrospectively evaluated the clinical records of patients who underwent RAPN between 2010 and 2013 for clinical N0M0 renal tumours in four international centres that completed all the data required for the Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database. All patients underwent preoperative computed tomography or magnetic resonance imaging to define the clinical stage and anatomical characteristics of the tumours. PADUA and R.E.N.A.L. scores were retrospectively assessed in each centre. Univariate and multivariate analyses were used to evaluate the correlations between age, gender, Charlson comorbidity index, clinical tumour size, PADUA and R.E.N.A.L. complexity group categories and warm ischaemia time (WIT) of >20 min, urinary calyceal system closure, and grade of postoperative complications. RESULTS: Overall, 277 patients were evaluated. The median (interquartile range) tumour size was 33.0 (22.0-43.0) mm. The median PADUA and R.E.N.A.L. scores were eight and seven, respectively; 112 (40.4%), 86 (31.0%) and 79 (28.5%) patients were classified in the low-, intermediate- or high-complexity group according to PADUA score, while 118 (42.5%), 139 (50.1%) and 20 (7.2%) were classified in the low-, intermediate- or high-complexity group according to R.E.N.A.L. score, respectively. Both nephrometry tools significantly correlated with perioperative outcomes at univariate and multivariate analyses. CONCLUSION: A precise stratification of patients before PN is recommended to consider both the potential threats and benefits of nephron-sparing surgery. In our present analysis, both PADUA and R.E.N.A.L. were significantly associated with predicting prolonged WIT and high-grade postoperative complications after RAPN.

The European Association of Urology Robotic Urology Section (ERUS) survey of robot-assisted radical prostatectomy (RARP).

OBJECTIVE: To evaluate surgeons adherence to current clinical practice, with the available evidence, for robot-assisted radical prostatectomy (RARP) and offer a baseline assessment to measure the impact of the Pasadena recommendations. Recently, the European Association of Urology Robotic Urology Section (ERUS) supported the Pasadena Consensus Conference on best practices in RARP. SUBJECTS AND METHODS: This survey was performed in January 2012. A specific questionnaire was sent, by e-mail, to 145 robotic surgeons who were included in the mailing-list of ERUS members and working in different urological institutions. Participating surgeons were invited to answer a multiple-choice questionnaire including 24-items evaluating the main RARP surgical steps. RESULTS: In all, 116 (79.4%) invited surgeons answered the questionnaire and accepted to participate to the ERUS survey. In all, 47 (40.5%) surgeons performed >100 RARPs; 41 (35.3%) between 50 and 100, and 28 (24.1%) <50 yearly. The transperitoneal, antegrade technique was the preferred approach. Minimising bladder neck dissection and the use of athermal dissection of the neurovascular bundles (NVBs) were also popular. There was more heterogeneity in the use of energy for seminal vesicle dissection, the preservation of the tips of the seminal vesicle and the choice between intra- and interfascial planes during the antero-lateral dissection of the NVBs. There was also large variability in the posterior and/or anterior reconstruction steps. CONCLUSIONS: The present study is the first international survey evaluating surgeon preferences during RARP. Considering that the results were collected before the publication of the Pasadena recommendations, the data might be considered an important baseline evaluation to test the dissemination and effects of the Pasadena recommendations in subsequent years.

Development and Validation of a Nomogram Predicting Intraoperative Adverse Events During Robot-assisted Partial Nephrectomy.

BACKGROUND: Ability to predict the risk of intraoperative adverse events (IOAEs) for patients undergoing partial nephrectomy (PN) can be of great clinical significance. OBJECTIVE: To develop and internally validate a preoperative nomogram predicting IOAEs for robot-assisted PN (RAPN). DESIGN, SETTING, AND PARTICIPANTS: In this observational study, data for demographic, preoperative, and postoperative variables for patients who underwent RAPN were extracted from the Vattikuti Collective Quality Initiative (VCQI) database. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: IOAEs were defined as the occurrence of intraoperative surgical complications, blood transfusion, or conversion to open surgery/radical nephrectomy. Backward stepwise logistic regression analysis was used to identify predictors of IOAEs. The nomogram was validated using bootstrapping, the area under the receiver operating characteristic curve (AUC), and the goodness of fit. Decision curve analysis (DCA) was used to determine the clinical utility of the model. RESULTS AND LIMITATIONS: Among the 2114 patients in the study cohort, IOAEs were noted in 158 (7.5%). Multivariable analysis identified five variables as independent predictors of IOAEs: RENAL nephrometry score (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.02-1.25); clinical tumor size (OR 1.01, 95% CI 1.001-1.024); PN indication as absolute versus elective (OR 3.9, 95% CI 2.6-5.7) and relative versus elective (OR 4.2, 95% CI 2.2-8); Charlson comorbidity index (OR 1.17, 95% CI 1.05-1.30); and multifocal tumors (OR 8.8, 95% CI 5.4-14.1). A nomogram was developed using these five variables. The model was internally valid on bootstrapping and goodness of fit. The AUC estimated was 0.76 (95% CI 0.72-0.80). DCA revealed that the model was clinically useful at threshold probabilities >5%. Limitations include the lack of external validation and selection bias. CONCLUSIONS: We developed and internally validated a nomogram predicting IOAEs during RAPN. PATIENT SUMMARY: We developed a preoperative model than can predict complications that might occur during robotic surgery for partial removal of a kidney. Tests showed that our model is fairly accurate and it could be useful in identifying patients with kidney cancer for whom this type of surgery is suitable.

Off-clamp Versus On-clamp Robot-assisted Partial Nephrectomy: A Propensity-matched Analysis.

BACKGROUND: Partial nephrectomy is the preferred treatment option for the management of small renal masses. On-clamp partial nephrectomy is associated with a risk of ischemia and a greater loss of postoperative renal function, while the off-clamp procedure decreases the duration of renal ischemia, leading to better renal function preservation. However, the efficacy of the off- versus on-clamp partial nephrectomy for renal function preservation remains debatable. OBJECTIVE: To compare perioperative and functional outcomes following off- and on-clamp robot-assisted partial nephrectomy (RAPN). DESIGN, SETTING, AND PARTICIPANTS: This study used the prospective multinational collaborative Vattikuti Collective Quality Initiative (VCQI) database for RAPN. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary objective of this study was the comparison of perioperative and functional outcomes between patients who underwent off- and on-clamp RAPN. Propensity scores were calculated for age, sex, body mass index (BMI), renal nephrometry score (RNS) and preoperative estimated glomerular filtration rate (eGFR). RESULTS AND LIMITATIONS: Of the 2114 patients, 210 had undergone off-clamp RAPN and others on-clamp procedure. Propensity matching was possible for 205 patients in a 1:1 ratio. After matching, the two groups were comparable for age, sex, BMI, tumor size, multifocality, tumor side, face of tumor, RNS, polar location of the tumor, surgical access, and preoperative hemoglobin, creatinine, and eGFR. There was no difference between the two groups for intraoperative (4.8% vs 5.3%, p = 0.823) and postoperative (11.2% vs 8.3%, p = 0.318) complications. Need for blood transfusion (2.9% vs 0, p = 0.030) and conversion to radical nephrectomy (10.2% vs 1%, p < 0.001) were significantly higher in the off-clamp group. At the last follow-up, there was no difference between the two groups for creatinine and eGFR. The mean fall in eGFR at the last follow-up compared with that at baseline was equivalent between the two groups (-16.0 vs -17.3 ml/min, p = 0.985). CONCLUSIONS: Off-clamp RAPN does not result in better renal functional preservation. Alternatively, it may be associated with increased rates of conversion to radical nephrectomy and need for blood transfusion. PATIENT SUMMARY: With this multicentric study, we noted that performing robotic partial nephrectomy without clamping the blood supply to the kidney is not associated with better preservation of renal function. However, off-clamp partial nephrectomy is associated with increased rates of conversion to radical nephrectomy and blood transfusion.

Robot-assisted partial nephrectomy in morbidly obese patients: a VCQI database study.

To compare perioperative outcomes following robot-assisted partial nephrectomy (RAPN) in patients with morbid obesity (body mass index (BMI > 40 kg/m2)) and non-obese patients. Using the Vattikuti Collective quality initiative (VCQI) database for RAPN, data for morbidly obese and non-obese patients was obtained. Propensity scores were calculated for two treatment groups (morbidly obese vs. non-obese) for the following variables i.e. age, sex, tumor size, RNS, surgical access (retroperitoneal/transperitoneal) and estimated glomerular filtration rate (eGFR) to ensure comparability. The primary outcome for the study was comparison of trifecta between the two groups. In this study, 158 morbidly obese patients were matched with 158 non-obese patients undergoing RAPN. Two groups matched well for age, sex, tumor size, eGFR and RNS. There was no difference between two groups for ischemia time, blood loss, blood transfusion, conversion to radical nephrectomy, length of stay, intraoperative and postoperative complications. Operative time was longer in morbidly obese patients (median 210 min vs. 120 min, p = 0.000). On pathological analysis, malignant tumors were more likely in the morbidly obese group (83.1% vs.73.4%, p = 0.018). Trifecta outcomes were comparable between the two groups (60.1% vs. 63.3%, p = 0.563). The Median duration of follow-up was 12 months (1-96 months). The morbidly obese group had significantly higher day one creatinine (1.25 ± 0.7 vs. 1.07 ± 0.37, p = 0.001) and significantly lower day one eGFR (62.1 ± 19 vs. 69.2 ± 21, p = 0.018). However, there was no difference between the two groups for the last follow-up creatinine and eGFR. RAPN in morbidly obese patients is associated with equivalent perioperative outcomes compared to non-obese patients.

Cadaveric analysis of periprostatic nerve distribution: an anatomical basis for high anterior release during radical prostatectomy?

PURPOSE: An accurate, complete understanding of the prostate neuroanatomy is required to optimize nerve sparing techniques during radical prostatectomy. However, the precise topography and function of the periprostatic nerves remain contentious and there is uncertainty about which nerve sparing technique is most optimal. We accurately quantified the distribution, precise localization and cross-sectional area of periprostatic neural tissue using cadaveric specimens. MATERIALS AND METHODS: We analyzed 13 cadaveric hemipelves using hematoxylin and eosin stained sections from the base, mid zone and apex of each prostate. Each section was digitized and divided into 6 sectors numbered clockwise. Analysis was performed using National Institutes of Health ImageJ software to calculate the total periprostatic neural cross-sectional area per sector. RESULTS: Calculating the total neural cross-sectional area highlighted a decrease from prostate base to mid zone to apex of 24.7, 19.7 and 13.7 mm(2), respectively. Most neural tissue was located in the posterolateral region. However, the proportion surrounding the anterior part of the prostate increased toward the apex with a median of 6.0% and 7.6% at the base and mid zone regions, respectively, increasing to 11.2% at the apex. CONCLUSIONS: Simple numerical nerve quantification may be insufficient to accurately describe the periprostatic neural distribution. Calculating nerve bundle cross-sectional area confirmed that most neural tissue is in the posterolateral region, although the proportion located anterior increases from base to apex. Thus, higher release of the periprostatic fascia may be indicated toward the apex.

High-intensity focused ultrasound for localized prostate cancer: initial experience with a 2-year follow-up.

OBJECTIVE: To report on the short-term functional and oncological results, from one institution, of high-intensity focused ultrasound (HIFU) for treating localized prostate cancer. PATIENTS AND METHODS: Over a 3-year period, 43 patients with localized prostate cancer were scheduled for HIFU in the primary (31) and salvage (12) settings using a second-generation Ablatherm device (EDAP, Lyon, France). Oncological failure was defined by several criteria, including biochemical failure (assessed using both the Phoenix definition of the nadir + 2 ng/mL) and the current Food and Drug Administration (FDA) trial endpoint of a prostate-specific antigen (PSA) level of > or = 0.5 ng/mL, or starting salvage therapy, or the presence of cancer on biopsy after treatment. RESULTS: Three patients had their procedures abandoned due to technical limitations/rectal wall thickness. The mean PSA levels in the primary and salvage groups were 9.2 and 5.1 ng/mL, respectively. The mean HIFU treatment time in the primary and salvage groups was 71.1 and 63.3 min, respectively. Using the Phoenix definition of biochemical failure, HIFU treatment failed in 13 patients in the primary group (46%) and five in the salvage group. Using the FDA trial endpoint, HIFU failed in 21 patients in the primary group (75%) and eight in the salvage group. One man died from metastatic prostate cancer 18 months after salvage HIFU. There were two urethral strictures in the primary (7%) and one in the salvage treatment group. There were two prostato-rectal fistulae in the salvage HIFU group. CONCLUSIONS: HIFU is proposed to be a minimally invasive low-morbidity ablative treatment for localized prostate cancer, and with good efficacy. The present limited series is unable to support these claims. There were significant rates of complications and oncological failure in both the primary and salvage setting. As a result we have suspended our programme pending further evidence of its safety and efficacy.

Outcomes after robot-assisted laparoscopic radical prostatectomy.

Robot-assisted laparoscopic radical prostatectomy (RALRP) using the da Vinci surgical system is now in widespread use in many countries where economic conditions allow the installation of this expensive technology. Controversy has surrounded the procedure since it was first performed in 2000, with many critics highlighting the lack of evidence to support its use. However, despite the lack of level I evidence, many large studies of patients have confirmed that the procedure is feasible and safe, with low morbidity. Available longer-term oncological data seem to show that outcomes from the robotic approach at least match those of traditional open radical prostatectomy. Functional outcomes also seem satisfactory, although randomized controlled trials are lacking. This paper reviews the current status of RALRP with respect to perioperative data and complications and oncologic and functional outcomes.

Retroperitoneal Robotic Partial Nephrectomy: Systematic Review and Cumulative Analysis of Comparative Outcomes.

OBJECTIVES: To compare the outcomes of retroperitoneal vs transperitoneal approach for robot-assisted partial nephrectomy (RAPN). MATERIALS AND METHODS: A systematic review of the literature was performed through January 2018 using PubMed, Scopus, and Ovid databases. Article selection proceeded according to the search strategy based on PRISMA criteria. Only studies comparing retroperitoneal to transperitoneal approach for RAPN were deemed eligible for inclusion. RESULTS: Seven retrospective case-control studies were identified and included in the analysis, with a total number of 1379 patients (866 for transperitoneal group; 513 for retroperitoneal group). In the retroperitoneal group, tumors were slightly larger [weighted mean difference (WMD): 0.29 cm; 95% confidence interval (CI): 0.04-0.54; p = 0.02], and more frequently located posterior/lateral (odds ratio: 0.61; 95% CI: 0.41-0.90; p = 0.01). In two of the studies only posterior tumors had been included. Both operating time (WMD 20.17 min; 95% CI 6.46-33.88; p = 0.004) and estimated blood loss (WMD 54.57 mL; 95% CI 6.73-102.4; p = 0.03) were significantly lower in the retroperitoneal group. In addition, length of stay was significantly shorter in the retroperitoneal group (WMD 0.46 days; CI 95% 0.15-0.76; p = 0.003). No differences were found regarding overall (p = 0.67) and major (p = 0.82) postoperative complications, warm ischemia time (p = 0.96), and positive surgical margins (p = 0.95). CONCLUSIONS: Retroperitoneal RAPN can offer in select patients similar outcomes to those of the most common transperitoneal RAPN. Furthermore, it may be particularly advantageous for posterior upper pole and perihilar tumors and associated with reduction in operative time and hospital stay. Robotic surgeons should be ideally familiar with both approaches to adapt their surgical strategy to confront renal neoplasms from a position of technical advantage and ultimately optimize outcomes.

Ex vivo study of prostate cancer localization using rolling mechanical imaging towards minimally invasive surgery.

Rolling mechanical imaging (RMI) is a novel technique towards the detection and quantification of malignant tissue in locations that are inaccessible to palpation during robotic minimally invasive surgery (MIS); the approach is shown to achieve results of higher precision than is possible using the human hand. Using a passive robotic manipulator, a lightweight and force sensitive wheeled probe is driven across the surface of tissue samples to collect continuous measurements of wheel-tissue dynamics. A color-coded map is then generated to visualize the stiffness distribution within the internal tissue structure. Having developed the RMI device in-house, we aim to compare the accuracy of this technique to commonly used methods of localizing prostate cancer in current practice: digital rectal exam (DRE), magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS) biopsy. Final histology is the gold standard used for comparison. A total of 126 sites from 21 robotic-assisted radical prostatectomy specimens were examined. Analysis was performed for sensitivity, specificity, accuracy, and predictive value across all patient risk profiles (defined by PSA, Gleason score and pathological score). Of all techniques, pre-operative biopsy had the highest sensitivity (76.2%) and accuracy (64.3%) in the localization of tumor in the final specimen. However, RMI had a higher sensitivity (44.4%) and accuracy (57.9%) than both DRE (38.1% and 52.4%, respectively) and MRI (33.3% and 57.9%, respectively). These findings suggest a role for RMI towards MIS, where haptic feedback is lacking. While our approach has focused on urological tumors, RMI has potential applicability to other extirpative oncological procedures and to diagnostics (e.g., breast cancer screening).

Rolling mechanical imaging for tissue abnormality localization during minimally invasive surgery.

We describe a novel approach for the localization of tissue abnormalities during minimally invasive surgery using a force-sensitive wheeled probe. The concept is to fuse the kinaesthetic information from the wheel-tissue rolling interaction into a pseudocolor rolling mechanical image (RMI) to visualize the spatial variation of stiffness within the internal tissue structure. Since tissue abnormalities are often firmer than the surrounding organ or parenchyma, a surgeon then can localize abnormalities by analyzing the image. Initially, a testing facility for validating the concept in an ex vivo setting was developed and used to investigate rolling "wheel-tissue" interaction. A silicone soft-tissue phantom with embedded hard nodules was constructed to allow for experimental comparison between an RMI and a known soft-tissue structure. Tests have also been performed on excised porcine organs to show the efficacy of the method when applied to biological soft tissues. Results indicate that the RMI technique is particularly suited to identifying the stiffness distribution within a tissue sample, as the continuous force measurement along a given rolling trajectory provides repeatable information regarding relative variations in the normal tissue response. When compared to multiple discrete uniaxial indentations, the continuous measurement approach of RMI is shown to be more sensitive and facilitates coverage of a large area in a short period of time. Furthermore, if parametric classification of tissue properties based on a uniaxial tissue indentation model is desirable, the rolling indentation probe can be easily employed as a uniaxial indenter.