Society of Robotic Surgery review: recommendations regarding the risk of COVID-19 transmission during minimally invasive surgery.

OBJECTIVES: To determine the risk of COVID-19 transmission during minimally invasive surgical (MIS) procedures METHODS: Surgical society statements regarding the risk of COVID transmission during MIS procedures were reviewed. In addition, the available literature on COVID-19 and other viral transmission in CO2 pneumoperitoneum, as well as the presence of virus in the plume created by electrocautery during MIS was reviewed. The society recommendations were compared to the available literature on the topic to create our review and recommendations to mitigate COVID-19 transmission. RESULTS: The recommendations promulgated by various surgical societies evolved over time as more information became available on COVID-19 transmission. Review of the available literature on the presence of COVID-19 in CO2 pneumoperitoneum was inconclusive. There is no clear evidence of the presence of COVID-19 in plume created by electrocautery. Technologies to reduce CO2 pneumoperitoneum release into the operating room as well as filter viral particles are available and should reduce the exposure risk to operating room personnel. CONCLUSION: There is no clear evidence of COVID-19 virus in the CO2 used during MIS procedures or in the plume created by electrocautery. Until the presence or absence of COVID-19 viral particles has been clearly established, measures to mitigate CO2 and surgical cautery plume release into the operating room should be performed. Further study on the presence of COVID-19 in MIS pneumoperitoneum and cautery plume is needed.

Suture techniques during laparoscopic and robot-assisted partial nephrectomy: a systematic review and quantitative synthesis of peri-operative outcomes.

OBJECTIVE: To summarize the available evidence on renorrhaphy techniques and to assess their impact on peri-operative outcomes after minimally invasive partial nephrectomy (MIPN). MATERIALS AND METHODS: A systematic review of the literature was performed in January 2018 without time restrictions, using MEDLINE, Cochrane and Web of Science databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement recommendations. Studies providing sufficient details on renorrhaphy techniques during laparoscopic or robot-assisted partial nephrectomy and comparative studies focused on peri-operative outcomes were included in qualitative and quantitative analyses, respectively. RESULTS: Overall, 67 and 19 studies were included in the qualitative and quantitative analyses, respectively. The overall quality of evidence was low. Specific tumour features (i.e. size, hilar location, anatomical complexity, nearness to renal sinus and/or urinary collecting system), surgeon's experience, robot-assisted technology, as well as the aim of reducing warm ischaemia time and the amount of devascularized renal parenchyma preserved represented the key factors driving the evolution of the renorrhaphy techniques during MIPN over the past decade. Quantitative synthesis showed that running suture was associated with shorter operating and ischaemia time, and lower postoperative complication and transfusion rates than interrupted suture. Barbed suture had lower operating and ischaemia time and less blood loss than non-barbed suture. The single-layer suture technique was associated with shorter operating and ischaemia time than the double-layer technique. No comparisons were possible concerning renal functional outcomes because of non-homogeneous data reporting. CONCLUSIONS: Renorrhaphy techniques significantly evolved over the years, improving outcomes. Running suture, particularly using barbed wires, shortened the operating and ischaemia times. A further advantage could derive from avoiding a double-layer suture.

NCCN Guidelines Insights: Kidney Cancer, Version 2.2020.

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for the clinical management of patients with clear cell and non-clear cell renal cell carcinoma, and are intended to assist with clinical decision-making. These NCCN Guidelines Insights summarize the NCCN Kidney Cancer Panel discussions for the 2020 update to the guidelines regarding initial management and first-line systemic therapy options for patients with advanced clear cell renal cell carcinoma.

Urinary aquaporin 1 and perilipin 2: Can these novel markers accurately characterize small renal masses and help guide patient management?

OBJECTIVE: To evaluate the role of urine aquaporin 1 and perilipin 2 as biomarkers adjunct to renal mass biopsy in guiding the management of patients with small renal masses. METHODS: Preoperative aquaporin 1 and perilipin 2 levels in 57 patients with small renal masses undergoing partial nephrectomy were analyzed and compared with postoperative tumor histology. An algorithm was created utilizing aquaporin 1 and perilipin 2 in conjunction with renal mass biopsy. Cut-off values were implemented to maximize biomarker sensitivity and specificity. Renal mass biopsy utilization and intervention were then compared with rates in traditional renal mass biopsy algorithms. RESULTS: All clear cell and papillary renal cell carcinomas were correctly identified and assigned to the treatment path. All benign lesions were correctly sorted to a confirmatory renal mass biopsy path. Two chromophobe masses did not have elevated aquaporin 1 and perilipin 2, and would require renal mass biopsy. Compared with protocols that call for all small renal masses to be biopsied, confirmatory renal mass biopsy could have been safely avoided in 74% of patients with elevated aquaporin 1 and perilipin 2. Compared with protocols that do not utilize renal mass biopsy, surgical intervention would have been avoided in 23% of patients with benign masses. CONCLUSIONS: Aquaporin 1 and perilipin 2 possess high sensitivity and specificity for detecting clear cell and papillary renal cell carcinoma. Use of these markers might compliment renal mass biopsy in the characterization of small renal masses.

Kidney Cancer, Version 2.2017, NCCN Clinical Practice Guidelines in Oncology.

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for the clinical management of patients with clear cell and non-clear cell renal carcinoma. These guidelines are developed by a multidisciplinary panel of leading experts from NCCN Member Institutions consisting of medical oncologists, hematologists and hematologic oncologists, radiation oncologists, urologists, and pathologists. The NCCN Guidelines are in continuous evolution and are updated annually or sometimes more often, if new high-quality clinical data become available in the interim.

Multicentre outcomes of robot-assisted partial nephrectomy after major open abdominal surgery.

OBJECTIVE: To evaluate the outcomes of robot-assisted partial nephrectomy RAPN after major prior abdominal surgery (PAS) using a large multicentre database. PATIENTS AND METHODS: We identified 1 686 RAPN from five academic centres between 2006 and 2014. In all, 216 patients had previously undergone major PAS, defined as having an open upper midline/ipsilateral incision. Perioperative outcomes were compared with those 1 470 patients who had had no major PAS. The chi-squared test and Mann-Whitney U-test were used for categorical and continuous variables, respectively. RESULTS: There was no statistically significant difference in Charlson comorbidity index, tumour size, R.E.N.A.L. nephrometry score or preoperative estimated glomerular filtration rate (eGFR) between the groups. Age and body mass index were higher in patients with PAS. The PAS group had a higher estimated blood loss (EBL) but this did not lead to a higher transfusion rate. A retroperitoneal approach was used more often in patients with major PAS (11.2 vs 5.4%), although this group did not have a higher percentage of posterior tumours (38.8 vs 43.3%, P = 0.286). Operative time, warm ischaemia time, length of stay, positive surgical margin, percentage change in eGFR, and perioperative complications were not significantly different between the groups. CONCLUSIONS: RAPN in patients with major PAS is safe and feasible, with increased EBL but no increased rate of transfusion. Patients with major PAS had almost twice the likelihood of having a retroperitoneal approach.

Urinary fistula after robot-assisted partial nephrectomy: a multicentre analysis of 1 791 patients.

OBJECTIVE: To evaluate the incidence of and risk factors for a urine leak in a large multicentre, prospective database of robot-assisted partial nephrectomy (RPN). PATIENTS AND METHODS: A database of 1 791 RPN from five USA centres was reviewed for urine leak as a complication of RPN. Patient and tumour characteristics were compared between patients with and those without postoperative urine leaks. Fisher's exact test was used for qualitative variables and Wilcoxon sum-rank tests were used for quantitative variables. A review of the literature on PN and urine leak was conducted. RESULTS: Urine leak was noted in 14/1 791 (0.78%) patients who underwent RPN. The mean (sd) nephrometry score of the entire cohort was 7.2 (1.9), and 8.0 (1.9) in patients who developed urine leak. The median (range) postoperative day of presentation was 13 (3-32) days. Patients with urine leak presented in delayed fashion with fever (two of the 14 patients, 14%), gastrointestinal complaints (four patients, 29%), and pain (five patients, 36%). Eight of the 14 patients (57%) required admission, while eight (57%) and nine (64%) had a drain or stent placed, respectively. Drains and stents were removed after a median (range) of 8 (4-13) days and 21 (8-83) days, respectively. Variables associated with urine leak included tumour size (P = 0.021), hilar location (P = 0.025), operative time (P = 0.006), warm ischaemia time (P = 0.005), and pelvicalyceal repair (P = 0.018). Upon literature review, the historical incidence of urine leak ranged from 1.0% to 17.4% for open PN and 1.6-16.5% for laparoscopic PN. CONCLUSION: The incidence of urine leak after RPN is very low and may be predicted by some preoperative factors, affording better patient counselling of risks. The low urinary leak rate may be attributed to the enhanced visualisation and suturing technique that accompanies the robotic approach.

Tumor diameter accurately predicts perioperative outcomes in T1 renal cancer treated with robot-assisted partial nephrectomy.

PURPOSE: To compare diameter as a continuous variable with categorical R.E.N.A.L. nephrometry score (RNS) in predicting surgical outcomes of robotic partial nephrectomy (RPN). METHODS: We retrospectively reviewed consecutive patients receiving RPN at our institution between July 2007 and June 2014 (n = 286). Three separate multivariate analyses were performed to assess the relationship between RNS components (R = radius, E = endophyticity, N = nearness to collecting system, L = location relative to polar lines), total RNS, and diameter as a continuous variable with operating time, warm ischemia time (WIT), and estimated blood loss (EBL). Each linear regression model's quality of fit to the data was assessed with coefficients of determination (R 2). RESULTS: Continuous tumor diameter and total RNS were each significantly correlated to operative time, EBL, and WIT (p < 0.001). Categorical R related to operative time (R = 2 vs. R = 1, p = 0.001; R = 3 vs. R = 1, p = 0.001) and WIT (R = 2 vs. R = 1, p = 0.003; R = 3 vs. R = 1, p = 0.016), but not to EBL. For each of these outcomes, diameter outperformed both R and total RNS, as assessed by R 2. Age, body mass index, Charlson Comorbidity Index, and anterior versus posterior location did not correlate with surgical outcomes. CONCLUSIONS: In this series of RPN from a high-volume center, surgical outcomes more closely related to tumor diameter than RNS. While RNS provides surgeons a standardized tool for preoperative planning of renal masses, tumor size may be employed as a more familiar measurement when counseling patients on potential outcomes.

Trifecta and optimal perioperative outcomes of robotic and laparoscopic partial nephrectomy in surgical treatment of small renal masses: a multi-institutional study.

OBJECTIVE: To compare the perioperative outcomes of robotic partial nephrectomy (RPN) with laparoscopic PN (LPN) performed for small renal masses (SRMs), in a large multi-institutional series and to define a new composite outcome measure, termed 'optimal outcome' for the RPN group. PATIENTS AND METHODS: Retrospective review of 2392 consecutive cases of RPN and LPN performed in five high-volume centres from 2004 to mid-2013. We limited our study to SRMs and cases performed by surgeons with significant expertise with the technique. The Trifecta was defined as negative surgical margin, zero perioperative complications and a warm ischaemia time of ≤25 min. The 'optimal outcome' was defined as achievement of Trifecta with addition of 90% estimated glomerular filtration rate preservation and no chronic kidney disease stage upgrading. Univariable and multivariable analysis were used to identify factors predicting Trifecta and 'optimal outcome' achievement. RESULTS: In all, 1185 RPN and 646 LPN met our inclusion criteria. Patients in the RPN group were older and had a higher median Charlson comorbidity index and higher R.E.N.A.L. nephrometry score. The RPN group had lower warm ischaemia time (18 vs 26 min), overall complication rate (16.2% vs 25.9%), and positive surgical margin rate (3.2% vs. 9.7%). There was a significantly higher Trifecta rate for RPN (70% vs 33%) and the rate of achievement of 'optimal outcome' for the RPN group was 38.5%. CONCLUSIONS: In this large multi-institutional series RPN was superior to LPN for perioperative surgical outcomes measured by Trifecta. Patients in the RPN group had better outcomes for all three components of Trifecta compared with their LPN counterparts. Our more strict definition for 'optimal outcome' might be a better tool for assessing perioperative and functional outcomes after minimally invasive PN. This tool needs to be externally validated.

Testicular Cancer, Version 2.2015.

Germ cell tumors (GCTs) account for 95% of testicular cancers. Testicular GCTs constitute the most common solid tumor in men between the ages of 20 and 34 years, and the incidence of testicular GCTs has been increasing in the past 2 decades. Testicular GCTs are classified into 2 broad groups--pure seminoma and nonseminoma--which are treated differently. Pure seminomas, unlike nonseminomas, are more likely to be localized to the testis at presentation. Nonseminoma is the more clinically aggressive tumor associated with elevated serum concentrations of alphafetoprotein (AFP). The diagnosis of a seminoma is restricted to pure seminoma histology and a normal serum concentration of AFP. When both seminoma and elements of a nonseminoma are present, management follows that for a nonseminoma. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Testicular Cancer outline the diagnosis, workup, risk assessment, treatment, and follow-up schedules for patients with both pure seminoma and nonseminoma.

Kidney cancer, version 3.2015.

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for the clinical management of patients with clear cell and non-clear cell renal carcinoma. These NCCN Guidelines Insights highlight the recent updates/changes in these guidelines, and updates include axitinib as first-line treatment option for patients with clear cell renal carcinoma, new data to support pazopanib as subsequent therapy for patients with clear cell carcinoma after first-line treatment with another tyrosine kinase inhibitor, and guidelines for follow-up of patients with renal cell carcinoma.

Hemorrhagic Cystitis Requiring Bladder Irrigation is Associated with Poor Mortality in Hospitalized Stem Cell Transplant Patients.

PURPOSE: To evaluate the overall prognosis of post-stem cell transplant inpatients who required continuous bladder irrigation (CBI) for hematuria. MATERIALS AND METHODS: We performed a retrospective analysis of adult stem cell transplant recipients who received CBI for de novo hemorrhagic cystitis as inpatients on the bone marrow transplant service at Washington University from 2011-2013. Patients who had a history of genitourinary malignancy and/or recent surgical urologic intervention were excluded. Multiple variables were examined for association with death. RESULTS: Thirty-three patients met our inclusion criteria, with a mean age of 48 years (23-65). Common malignancies included acute myelogenous leukemia (17/33, 57%), acute lymphocytic leukemia (3/33, 10%), and peripheral T cell lymphoma (3/33, 10%). Median time from stem cell transplant to need for CBI was 2.5 months (0 days-6.6 years). All patients had previously undergone chemotherapy (33/33, 100%) and 14 had undergone prior radiation therapy (14/33, 42%). Twenty-eight patients had an infectious disease (28/33, 85%), most commonly BK viremia (19/33, 58%), cytomegalovirus viremia (17/33, 51%), and bacterial urinary tract infection (8/33, 24%). Twenty-two patients expired during the same admission as CBI treatment (22/33 or 67% of total patients, 22/28 or 79% of deaths), with a 30-day mortality of 52% and a 90-day mortality of 73% from the start of CBI. CONCLUSIONS: Hemorrhagic cystitis requiring CBI is a symptom of severe systemic disease in stem cell transplant patients. The need for CBI administration may be a marker for mortality risk from a variety of systemic insults, rather than directly attributable to the hematuria.

Evaluation of renal mass biopsy risk stratification algorithm for robotic partial nephrectomy--could a biopsy have guided management?

PURPOSE: We evaluated a published biopsy directed small renal mass management algorithm using a large cohort of patients who underwent robotic partial nephrectomy for tumors 4 cm or smaller. MATERIALS AND METHODS: A simplified algorithm of biopsy directed small renal mass management previously reported using risk stratified biopsies was applied to 1,175 robotic partial nephrectomy cases from 5 academic centers. A theoretical assumption was made of perfect biopsies that were feasible for all patients and had 100% concordance to final pathology. Pathology risk groups were benign, favorable, unfavorable and intermediate. The algorithm assigned favorable or intermediate tumors smaller than 2 cm to active surveillance and unfavorable or intermediate 2 to 4 cm tumors to treatment. Higher surgical risk patients were defined as ASA® 3 or greater and age 70 years or older. RESULTS: Patients were assigned to the pathology risk groups of benign (23%), favorable (13%), intermediate (51%) and unfavorable (12%). Patients were also assigned to the management groups of benign pathology (275, 23%), active surveillance (336, 29%) and treatment (564, 48%). Most of the 611 (52%) patients in the benign or active surveillance groups were low surgical risk and had safe treatment (2.6% high grade complications). A biopsy may not have been feasible or accurate in some tumors that were anterior (378, 32%), hilar (93, 7.9%) or less than 2 cm (379, 32%). Of 129 (11%) high surgical risk patients the biopsy algorithm assigned 70 (54%) to benign or active surveillance groups. CONCLUSIONS: The theoretical application of a biopsy driven, risk stratified small renal mass management algorithm to a large robotic partial nephrectomy database suggests that about half of the patients might have avoided surgery. Despite the obvious limitations of a theoretical assumption of all patients receiving a perfect biopsy, the data support the emerging role of renal mass biopsies to guide management, particularly in high surgical risk patients.

Port site metastasis after surgery for renal cell carcinoma: harbinger of future metastasis.

PURPOSE: Port site metastasis is a rare occurrence after minimally invasive treatment for renal cell carcinoma. However, its prognostic implications are unclear because reports in the literature are heterogeneous in detail and followup. We clarify the significance of port site metastasis in cancer specific survival and broaden our understanding of this phenomenon. MATERIALS AND METHODS: A MEDLINE® search for published studies of renal cell carcinoma port site metastasis was performed. Contributing factors to port site metastasis, stage, Fuhrman grade, pathology, port site metastasis treatment method, followup protocol and long-term outcomes were collected. The corresponding authors of each publication were contacted to fill in details and provide long-term outcomes. We added 1 case from our recent experience. RESULTS: A total of 16 cases from 12 authors (including ourselves) were found. Of the 12 authors 8 were available for correspondence and 9 cases were updated. Eventual outcomes were available for 11 of the 16 cases and survival curves showed poor prognosis with a 31.8% overall 1-year survival rate. Of the 16 cases 12 were radical nephrectomy and 4 were partial nephrectomy, and 13 involved multiple metastases in addition to the port site metastasis. Nine of the cases had no identifiable technical reason for port site metastasis formation such as specimen morcellation, absence of entrapment or tumor rupture. These tumors were uniformly aggressive, Fuhrman grade 3 or higher. CONCLUSIONS: Port site metastasis after minimally invasive surgery for renal cell carcinoma is a rare occurrence with a poor prognosis. In most cases port site metastasis is not an isolated metastasis but instead is a harbinger of progressive disease. While technical factors can have a role in port site metastasis formation, it appears that biological factors like high tumor grade also contribute.

Institutional Review Board approval and innovation in urology: current practice and safety issues.

OBJECTIVE: To retrospectively review recent publications describing novel procedures/techniques, and describe the Institutional Review Board (IRB)/ethics approval process and potential ethical dilemmas in their reporting. MATERIALS AND METHODS: We searched PubMed for papers about innovative or novel procedures/techniques between 2011 and August 2012. A query of titles/abstracts in the Journal of Urology, Journal of Endourology, European Urology, BJU International, and Urology identified relevant papers. These results were reviewed for human studies that described an innovative technique, procedure, approach, initial series, and/or used new technology. RESULTS: In all, 91 papers met criteria for inclusion; 25 from the Journal of Endourology, 14 from the Journal of Urology, nine from European Urology, 15 from the BJU International and 28 from Urology. IRB/ethics approval was given for an experimental procedure or database in 24% and 22%, respectively. IRB/ethics approval was not mentioned in 52.7% of studies. CONCLUSIONS: Published IRB/ethics approvals for innovative techniques are heterogeneous including database, retrospective, and prospective approvals. Given the concept that innovations are likely not in the legal or ethical standard of care, strong consideration should be given to obtaining IRB/ethics approval before the actual procedure, instead of approval to merely report database outcomes.

A multicentre matched-pair analysis comparing robot-assisted versus open partial nephrectomy.

OBJECTIVE: To compare the perioperative, pathological and functional outcomes in two contemporary, large series of patients in different institutions and who underwent open partial nephrectomy (OPN) or robot-assisted PN (RAPN) for suspected renal tumours. PATIENTS AND METHODS: This was a retrospective, multicentre, international, matched-pair analysis comparing patients who underwent RAPN or OPN for suspected renal cell carcinoma. Data on patients who underwent OPN were extracted by an Italian observational registry collecting data from 19 different centres. Data on patients who received RAPN were extracted from a multicentre, international database collecting cases treated in four high-volume referral centres of robotic surgery. The matching was in a 1:1 ratio for the surgical approach and included 200 patients in each arm. RESULTS: The mean warm ischaemia time was shorter in the OPN group than in the RAPN group, at a mean (SD) of 15.4 (5.9) vs 19.2 (7.3) min (P < 0.001). Conversely, the median (interquartile range) estimated blood loss was 150 (100-300) mL in the OPN group and 100 (50-150) mL in the RAPN group (P < 0.001). There were no differences in operating time (P = 0.18) and the intraoperative complication rate (P = 0.31) between the approaches. Postoperative complications were recorded in 43 (21.5%) patients who underwent OPN and in 28 (14%) who received RAPN (P = 0.02). Moreover, major complications (grade 3-4) were reported in nine (4.5%) patients after OPN and in nine (4.5%) after RAPN. Positive margins were detected in nine (5.5%) patients after OPN and in nine (5.7%) after RAPN (P = 0.98). The mean (SD) 3-month estimated glomerular filtration rate declined by 16.6 (18.1) mL/min from the preoperative value in the OPN group and by 16.4 (22.9) mL/min in the RAPN group (P = 0.28). CONCLUSION: RAPN can achieve equivalent perioperative, early oncological and functional outcomes as OPN. Moreover, RAPN is a less invasive approach, offering a lower risk of bleeding and postoperative complications than OPN.

Kidney cancer, version 2.2014.

These NCCN Guidelines Insights highlight treatment recommendations and updates specific to the management of patients with advanced non-clear cell carcinoma included in the 2014 version of the NCCN Clinical Practice Guidelines in Oncology for Kidney Cancer.

Mechanisms of cardiac and renal dysfunction in patients dying of sepsis.

RATIONALE: The mechanistic basis for cardiac and renal dysfunction in sepsis is unknown. In particular, the degree and type of cell death is undefined. OBJECTIVES: To evaluate the degree of sepsis-induced cardiomyocyte and renal tubular cell injury and death. METHODS: Light and electron microscopy and immunohistochemical staining for markers of cellular injury and stress, including connexin-43 and kidney-injury-molecule-1 (Kim-1), were used in this study. MEASUREMENTS AND MAIN RESULTS: Rapid postmortem cardiac and renal harvest was performed in 44 septic patients. Control hearts were obtained from 12 transplant and 13 brain-dead patients. Control kidneys were obtained from 20 trauma patients and eight patients with cancer. Immunohistochemistry demonstrated low levels of apoptotic cardiomyocytes (<1-2 cells per thousand) in septic and control subjects and revealed redistribution of connexin-43 to lateral membranes in sepsis (P < 0.020). Electron microscopy showed hydropic mitochondria only in septic specimens, whereas mitochondrial membrane injury and autophagolysosomes were present equally in control and septic specimens. Control kidneys appeared relatively normal by light microscopy; 3 of 20 specimens showed focal injury in approximately 1% of renal cortical tubules. Conversely, focal acute tubular injury was present in 78% of septic kidneys, occurring in 10.3 ± 9.5% and 32.3 ± 17.8% of corticomedullary-junction tubules by conventional light microscopy and Kim-1 immunostains, respectively (P < 0.01). Electron microscopy revealed increased tubular injury in sepsis, including hydropic mitochondria and increased autophagosomes. CONCLUSIONS: Cell death is rare in sepsis-induced cardiac dysfunction, but cardiomyocyte injury occurs. Renal tubular injury is common in sepsis but presents focally; most renal tubular cells appear normal. The degree of cell injury and death does not account for severity of sepsis-induced organ dysfunction.

Off-clamp robotic partial nephrectomy is a safe and effective approach for patients with T1b or greater renal tumors.

Robotic partial nephrectomy (RPN) is a gold standard treatment for focal kidney tumors. Off-clamp RPN avoids prolonged ischemia times. We sought to evaluate the safety and efficacy of off-clamp RPN in patients with renal tumors > 4 centimeters (cm). From 2007 to 2021, we examined patients who underwent RPN for cT1b-T2N0M0 renal tumors. Preoperative, intraoperative, and postoperative outcomes were examined for patients who underwent on or off-clamp RPN. Patients with cT1b tumors (4-7 cm) who underwent either approach were retrospectively propensity-matched based on renal function and tumor size. Of 225 patients, on-clamp RPN was employed in 147 patients, while 78 patients underwent an off-clamp approach. Preoperative estimated glomerular filtration rate (eGFR) was significantly lower in the off-clamp group (p = 0.026). Mean nephrometry scores and mean tumor sizes were similar between cohorts. Average estimated blood loss (EBL) and operative times were similar. Major complication risk was 4.4% lower in the off-clamp group. Blood transfusion rate was 5.6% lower in the off-clamp group. Patients in the off-clamp cohort experienced a < 2% higher risk of positive margins. Postoperative eGFR was more favorable for off-clamp RPN following surgery at 1 year. The propensity-matched analysis demonstrated similar intraoperative outcomes. Blood transfusion rate was significantly lower at 1.5% for patients who underwent off-clamp RPN (p = 0.03). Risk of a major complication was 6.1% lower in the off-clamp RPN cohort, while postoperative eGFR and positive margin rates were similar between off and on-clamp groups. A non-inferior approach for patients with cT1b-T2N0M0 and moderately complex localized renal masses is off-clamp RPN.

Positive surgical margins in robot-assisted partial nephrectomy: a multi-institutional analysis of oncologic outcomes (leave no tumor behind).

PURPOSE: Expanding indications for robot-assisted partial nephrectomy raise major oncologic concerns for positive surgical margins. Previous reports showed no correlation between positive surgical margins and oncologic outcomes. We report a multi-institutional experience with the oncologic outcomes of positive surgical margins on robot-assisted partial nephrectomy. MATERIALS AND METHODS: Pathological and clinical followup data were reviewed from an institutional review board approved, prospectively maintained joint database from 5 institutions. Tumors with malignant pathology were isolated and statistically analyzed for demographics and oncologic followup. The log rank test was used to compare recurrence-free and metastasis-free survival between patients with positive and negative surgical margins. The proportional hazards method was used to assess the influence of multiple factors, including positive surgical margins, on recurrence and metastasis. RESULTS: A total of 943 robot-assisted partial nephrectomies for malignant tumors were successfully completed. Of the patients 21 (2.2%) had positive surgical margins on final pathological assessment, resulting in 2 groups, including the 21 with positive surgical margins and 922 with negative surgical margins. Positive surgical margin cases had higher recurrence and metastasis rates (p<0.001). As projected by the Kaplan-Meier method in the population as a whole at followup out to 63.6 months, 5-year recurrence-free and metastasis-free survival was 94.8% and 97.5%, respectively. There was a statistically significant difference in recurrence-free and metastasis-free survival between patients with positive and negative surgical margins (log rank test<0.001), which favored negative surgical margins. Positive surgical margins showed an 18.4-fold higher HR for recurrence when adjusted for multiple tumors, tumor size, tumor growth pattern and pathological stage. CONCLUSIONS: Positive surgical margins on final pathological evaluation increase the HR of recurrence and metastasis. In addition to pathological and molecular tumor characteristics, this should be considered to plan appropriate management.