Preoperative proteinuria is associated with increased rates of acute kidney injury after partial nephrectomy

ABSTRACT Purpose We investigated the association between preoperative proteinuria and early postoperative renal function after robotic partial nephrectomy (RPN). Patients and Methods We retrospectively reviewed 1121 consecutive RPN cases at a single academic center from 2006 to 2016. Patients without pre-existing CKD (eGFR≥60 mL/min/1.73m2) who had a urinalysis within 1-month prior to RPN were included. The cohort was categorized by the presence or absence of preoperative proteinuria (trace or greater (≥1+) urine dipstick), and groups were compared in terms of clinical and functional outcomes. The incidence of acute kidney injury (AKI) was assessed using RIFLE criteria. Univariate and multivariable models were used to identify factors associated with postoperative AKI. Results Of 947 patients, 97 (10.5%) had preoperative proteinuria. Characteristics associated with preoperative proteinuria included non-white race (p<0.01), preoperative diabetes (p<0.01) and hypertension (HTN) (p<0.01), higher ASA (p<0.01), higher BMI (p<0.01), and higher Charlson score (p<0.01). The incidence of AKI was higher in patients with preoperative proteinuria (10.3% vs. 4.6%, p=0.01). The median eGFR preservation measured within one month after surgery was lower (83.6% vs. 91%, p=0.04) in those with proteinuria; however, there were no significant differences by 3 months after surgery or last follow-up visit. Independent predictors of AKI were high BMI (p<0.01), longer ischemia time (p<0.01), and preoperative proteinuria (p=0.04). Conclusion Preoperative proteinuria by urine dipstick is an independent predictor of postoperative AKI after RPN. This test may be used to identify patients, especially those without overt CKD, who are at increased risk for developing AKI after RPN.

Preoperative proteinuria is associated with increased rates of acute kidney injury after partial nephrectomy.

PURPOSE: We investigated the association between preoperative proteinuria and early postoperative renal function after robotic partial nephrectomy (RPN). PATIENTS AND METHODS: We retrospectively reviewed 1121 consecutive RPN cases at a single academic center from 2006 to 2016. Patients without pre-existing CKD (eGFR≥60 mL/min/1.73m2) who had a urinalysis within 1-month prior to RPN were included. The cohort was categorized by the presence or absence of preoperative proteinuria (trace or greater (≥1+) urine dipstick), and groups were compared in terms of clinical and functional outcomes. The incidence of acute kidney injury (AKI) was assessed using RIFLE criteria. Univariate and multivariable models were used to identify factors associated with postoperative AKI. RESULTS: Of 947 patients, 97 (10.5%) had preoperative proteinuria. Characteristics associated with preoperative proteinuria included non-white race (p<0.01), preoperative diabetes (p<0.01) and hypertension (HTN) (p<0.01), higher ASA (p<0.01), higher BMI (p<0.01), and higher Charlson score (p<0.01). The incidence of AKI was higher in patients with preoperative proteinuria (10.3% vs. 4.6%, p=0.01). The median eGFR preservation measured within one month after surgery was lower (83.6% vs. 91%, p=0.04) in those with proteinuria; however, there were no significant differences by 3 months after surgery or last follow-up visit. Independent predictors of AKI were high BMI (p<0.01), longer ischemia time (p<0.01), and preoperative proteinuria (p=0.04). CONCLUSION: Preoperative proteinuria by urine dipstick is an independent predictor of postoperative AKI after RPN. This test may be used to identify patients, especially those without overt CKD, who are at increased risk for developing AKI after RPN.

Predictors of positive surgical margins in patients undergoing partial nephrectomy: A large single-center experience.

OBJECTIVE: To identify preoperative factors that predict positive surgical margins in partial nephrectomy. MATERIAL AND METHODS: Using our institutional partial nephrectomy database, we investigated the patients who underwent partial nephrectomy for malignant tumors between January 2011 and December 2015. Patient, tumor, surgeon characteristics were compared by surgical margin status. Multivariable logistic regression was used to identify independent predictors of positive surgical margins. RESULTS: A total of 1025 cases were available for analysis, of which 65 and 960 had positive and negative surgical margins, respectively. On univariate analysis, positive margins were associated with older age (64.3 vs. 59.6, p<0.01), history of prior ipsilateral kidney surgery (13.8% vs. 5.6%, p<0.01), lower preoperative eGFR (74.7 mL/min/1.73 m2 vs. 81.2 mL/min/1.73 m2, p=0.01), high tumor complexity (31.8% vs. 19.0%, p=0.03), hilar tumor location (23.1% vs. 12.5%, p=0.01), and lower surgeon volume (p<0.01). Robotic versus open approach was not associated with the risk of positive margins (p=0.79). On multivariable analysis, lower preoperative eGFR, p=0.01), hilar tumor location (p=0.01), and lower surgeon volume (p<0.01) were found to be independent predictors of positive margins. CONCLUSION: In our large institutional series of partial nephrectomy cases, patient, tumor, and surgeon factors influence the risk of positive margins. Of these, surgeon volume is the single most important predictor of surgical margin status, indicating that optimal oncological outcomes are best achieved by high-volume surgeons.

Comparative Efficacy of Laparoscopic Versus Robotic Adrenalectomy for Adrenal Malignancy.

OBJECTIVE: To evaluate whether the technical advantages of robotic-assisted surgery over standard laparoscopy, which are well established for complex renal surgery, lead to variable surgical outcomes between laparoscopic adrenalectomy (LA) and robotic adrenalectomy (RA). METHODS: Using the National Cancer Database, we identified patients who underwent LA or RA for nonmetastatic primary adrenal malignancy from 2010 to 2013. Primary outcomes were need for open conversion, surgical margin status, and performance of regional lymphadenectomy. Secondary outcomes were length of stay, readmission, and perioperative mortality. Baseline characteristics and outcomes were compared between approaches using the chi-square, Fisher's exact, and Mann-Whitney U tests. RESULTS: Two hundred thirty-eight (82%) LA and 51 (18%) RA cases were identified. The LA and RA groups did not show any significant differences in terms of patient age, gender, race, Charlson score, tumor laterality, size (median 4.2-9.0 cm), histology, grade, hospital type, and case volume. The rate of open conversion was 5.9% for RA versus 17.2% for LA (P = .04). There were no significant differences in rates of positive margins, lymphadenectomy, inpatient stay, readmission, or mortality. CONCLUSION: RA significantly decreases need for open conversion compared to LA. Although RA improves technical feasibility, the oncological adequacy of minimally invasive resection remains uncertain.

Variability in Partial Nephrectomy Outcomes: Does Your Surgeon Matter?

BACKGROUND: Understanding physician-level discrepancies is increasingly a target of US healthcare reform for the delivery of quality-focused patient care. OBJECTIVE: To estimate the relative contributions of patient and surgeon characteristics to the variability in key outcomes after partial nephrectomy (PN). DESIGN, SETTING, AND PARTICIPANTS: Retrospective review of 1461 patients undergoing PN performed by 19 surgeons between 2011 and 2016 at a tertiary care referral center. INTERVENTION: PN for a renal mass. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS: Hierarchical linear and logistic regression models were built to determine the percentage variability contributed by fixed patient and surgeon factors on peri- and postoperative outcomes. Residual between- and within-surgeon variability was calculated while adjusting for fixed factors. RESULTS AND LIMITATIONS: On null hierarchical models, there was significant between-surgeon variability in operative time, estimated blood loss (EBL), ischemia time, excisional volume loss, length of stay, positive margins, Clavien complications, and 30-d readmission rate (all p<0.001), but not chronic kidney disease upstaging (p=0.47) or percentage preservation of glomerular filtration rate (p=0.49). Patient factors explained 82% of the variability in excisional volume loss and 0-32% of the variability in the remainder of outcomes. Quantifiable surgeon factors explained modest amounts (10-40%) of variability in intraoperative outcomes, and noteworthy amounts of variability (90-100%) in margin rates and patient morbidity outcomes. Immeasurable surgeon factors explained the residual variability in operative time (27%), EBL (6%), and ischemia time (31%). CONCLUSIONS: There is significant between-surgeon variability in outcomes after PN, even after adjusting for patient characteristics. While renal functional outcomes are consistent across surgeons, measured and unmeasured surgeon factors account for 18-100% of variability of the remaining peri- and postoperative variables. With the increasing utilization of value-based medicine, this has important implications for the goal of optimizing patient care. PATIENT SUMMARY: We reviewed our institutional database on partial nephrectomy performed for renal cancer. We found significant variability between surgeons for key outcomes after the intervention, even after adjusting for patient characteristics.

Robotic cold ischemia achieves comparable functional outcomes to open cold ischemia during partial nephrectomy for complex kidney tumors.

OBJECTIVES: To compare the perioperative and functional outcomes after open and robotic partial nephrectomy performed with cold ischemia. METHODS: A retrospective chart review was completed of consecutive patients who underwent partial nephrectomy with renal hypothermia between January 2011 and September 2016. The study cohort included both open (Open Cold Ischemia, OCI; n=170) and robotic (Robotic Cold Ischemia, RCI; n=31) patients with complex renal masses (R.E.N.A.L. score >7) who did not meet exclusion criteria. A modified intracorporeal technique 1 was utilized for the introduction of ice slush at the time of hilar clamping in the RCI group. Statistical testing was performed to compare key perioperative and functional outcomes after ensuring equilibration of both groups by clinicodemographic criteria. RESULTS: Both groups were statistically equivalent with respect to baseline characteristics. Median GFR preservation postoperatively was 86.7% for the open group and 86.6% in the robotic group (p=0.49). Cold ischemia time (CIT) in the open group was 35 minutes compared to 28 minutes (p = 0.03) in the robotic group. LOS was significantly shorter by 2 days (p < 0.01) in the robotic group. Positive margins was noted to be 17 (10%) in the open group and 2 (6.5%) patients in the robotic group (p=0.48). CONCLUSIONS: We demonstrate an effective and simplified method of intracorporeal ice cooling during robotic partial nephrectomy. Our data suggests that results with this approach compare favorably to open cold ischemia technique. Intracorporeal ice cooling can be considered when performing complex partial nephrectomies with ischemia times expected to exceed 25 minutes.

Single-Port Robot-Assisted Perineal Prostatectomy and Pelvic Lymphadenectomy: Step-by-Step Technique in a Cadaveric Model.

The envelope is constantly being pushed to minimize the invasiveness of prostate cancer surgery without compromising oncologic or functional outcomes. Transperitoneal robot-assisted radical prostatectomy has certainly accomplished these goals. However, it is our intent to push the envelope even further, that is, to minimize the invasiveness of already minimally invasive surgery. To accomplish this lofty goal, we borrowed the transperineal approach from open surgery and fused it with the latest robotic technology to innovate an extraperitoneal robotic prostatectomy technique that is less invasive than the traditional robotic technique.

Trifecta Outcomes in Multifocal Tumors: A Comparison Between Robotic and Open Partial Nephrectomy.

OBJECTIVES: To report a comparative analysis of outcomes in patients who underwent multiple excisions for unilateral synchronous multifocal renal tumors using both open and robotic approaches. METHODS: We retrospectively reviewed 110 patients who underwent robotic and open partial nephrectomy and had multiple tumor excisions in an ipsilateral kidney. "Trifecta" was defined as negative surgical margins, no urologic complications, and a glomerular filtration rate (GFR) preservation of ≥90% at last follow-up. Inverse probability of treatment weighting (IPTW) was applied to equilibrate treatment groups, minimize selection bias, and optimize inference on the basis of each patient's clinicodemographic characteristics. RESULTS: Sixty-eight robotic and 42 open patient approaches had sufficient data for IPTW. After weighting, there were no statistical differences in baseline characteristics between the two groups. On adjusted analyses, robotic partial nephrectomy achieved equivalent rates of trifecta to open surgery (16.3% vs 16.5%, p = 0.99), which persisted on subgroup analyses of patients with two (20.1% vs 23.7%, p = 0.82) or more than two tumors (6.8% vs 7.4%, p = 0.95). There were no differences between robotic and open cohorts for negative margin rates, absence of complications, or GFR ≥90%. The robotic cohort had a shorter mean length of stay (3.4 vs 4.9 days, p < 0.001). CONCLUSIONS: Surgical resection remains the mainstay for patients with unilateral, synchronous, and multifocal renal tumors. Our analysis found that both open and robotic approaches to partial nephrectomy are equally likely to achieve the "trifecta" outcome in an equilibrated high-risk group of patients. The robotic approach for these complex patients may be safe and feasible for a carefully selected group of patients.

Significance of the nonneoplastic renal parenchymal findings in robotic partial nephrectomy series.

AIM: To describe the pathological characteristics of the peritumoral non-neoplastic renal parenchyma (NNRP) and to investigate their impact on long-term renal function after partial nephrectomy. MATERIALS AND METHODS: In our institutional robotic partial nephrectomy database, we identified 394 cases with pathological assessment of the NNRP and long-term postoperative renal functional follow-up. The NNRP was classified as normal (healthy renal parenchyma) or abnormal, based on the presence of arteriosclerosis, glomerulosclerosis, interstitial fibrosis, interstitial inflammation, and/or tubulopapillary hyperplasia. The primary outcome was a ≥ 20% decline in estimated glomerular filtration rate (eGFR) at 6 and 12 months after surgery. Multivariable analysis was used to assess the association between NNRP and eGFR decline, with adjustment for demographic, clinical, and tumor factors. RESULTS: Overall, 250 (63.5%) pathological specimens had abnormal NNRP features. The most prevalent isolated benign pathological feature was glomerulosclerosis (18.0%), followed by arteriosclerosis (16.8%), interstitial inflammation (12.4%), interstitial fibrosis (1.2%), and tubulopapillary hyperplasia (0.4%). The abnormal NNRP group was associated with older age (p = .01), preoperative diabetes mellitus (p = .01), and preoperative hypertension (p = .01). The preoperative eGFR was significantly lower in the abnormal NNRP group (p = .01). NNRP abnormalities were not significantly associated with eGFR decline at either 6 or 12 months. The only independent predictor of eGFR decline was warm ischemia time (p = .01), and this association was only observed at 12 months. CONCLUSION: NNRP features are associated with preoperative comorbidities and lower baseline eGFR; however, they are not independent predictors of long-term renal functional preservation after partial nephrectomy.

Perinephric and Sinus Fat Invasion in Stage pT3a Tumors Managed by Partial Nephrectomy.

INTRODUCTION: We evaluated the influence of perinephric fat invasion (PFI) compared with sinus fat invasion (SFI) on disease-free survival (DFS) and cancer-specific survival (CSS) after partial nephrectomy (PN) for stage pT3a renal cell carcinoma (RCC). MATERIALS AND METHODS: Data were recorded from the consecutive records of patients who had undergone underwent PN for cT1-T2 RCC from 2007 to 2016. Of these patients, 143 had stage pT3a with SFI or PFI found on final pathologic examination. The demographic, perioperative, and pathologic variables were reviewed. DFS and CSS analyses were performed. The factors predicting disease progression in this population were assessed. RESULTS: After a median follow-up period of 28 months (range 15-41 months), 19 patients (13.3%) had developed recurrence, including 5 local and 14 distant metastases, with 11 cancer-specific deaths (7.7%). No differences were found in DFS (5 years, 60.9% vs. 55.3%; log-rank P = .7) or CSS (5 years, 81% vs. 74.2%; log-rank P = .8) between the SFI and PFI groups. For the pT3a fat invasion population, the 2- and 5-year DFS and CSS rates were 83.6% and 58.6% and 93.6% and 78%, respectively. SFI (P = .5) and positive surgical margins (P = .1) did not predict for progression. On multivariate Cox regression, increased tumor size (hazard ratio, 1.5; 95% confidence interval, 1.1-1.9; P < .01) and higher tumor grade (hazard ratio, 3.6; 95% confidence interval, 1.1-4.6; P = .04) were independent predictors of disease progression in the pT3a fat invasion population. CONCLUSION: In our series of patients with pT3a RCC after PN, SFI compared with PFI was not associated with an increased risk of progression or cancer-specific death.

Hilar Parenchymal Oversew: a novel technique for robotic partial nephrectomy hilar tumor renorrhaphy.

INTRODUCTION: A renorrhaphy technique which is effective for hemostasis but does not place undue tension on the branch vessels of the renal sinus remains one of the challenging steps after hilar tumor resection during robotic partial nephrectomy (RPN). The published V-hilar suture (VHS) technique is one option for reconstruction after an RPN involving the hilum. The objective of this video is to show a novel renorrhaphy technique, Hilar Parenchymal Oversew that has been effective for such cases. MATERIALS AND METHODS: We present two cases of RPN for renal hilar tumors. The first case depicts use of the VHS renorrhaphy technique for a tumor that abuts the renal hilum along 20% of its diameter. The second case demonstrates tumor resection and reconstruction for a tumor that has >50% involvement of the hilum along its diameter. After tumor resection, individual sinus vessels can be selectively oversewn with 2-0 Vicryl suture on SH needle. The remaining exposed parenchyma is controlled using the Hilar Parenchymal Oversew technique with a #0 Vicryl on CT-1 needle. RESULTS: For the Hilar Parenchymal Oversew surgery operative time was 225 min, estimated blood loss was 140 ml, warm ischemia time was 19 minutes, and there were no intraoperative complications. Pathology was consistent with clear cell renal cancer with negative margins. CONCLUSION: Robotic partial nephrectomy with the Hilar Parenchymal Oversew technique is a good alternative to VHS renorrhaphy in the management of renal hilar tumors "bulging" into the renal sinus with >50% of the tumor diameter abutting the hilum.

Robotic Total Pelvic Exenteration With Intracorporeal Sigmoid Conduit and Colostomy: Step-by-Step Technique.

OBJECTIVE: To describe our technique for robotic total pelvic exenteration with intracorporeal sigmoid conduit and colostomy using the da Vinci Si robot. METHODS: Three 8-mm robotic ports and two 12-mm laparoscopic ports are placed in a "W" configuration, approximately 2-3 cm more cephalad than for radical prostatectomy (Fig. 1). The robot is docked between the legs with the patient in steep Trendelenburg. The ureters are dissected out from the iliac vessels to the rectovesical pouch, where they are clipped and transected. The sigmoid colon is stapled across at the rectosigmoid junction and reflected into the abdomen. A posterior plane is developed below the rectum (Fig. 2A), if space allows, or through the rectum. The endopelvic fascia is exposed and incised bilaterally. After sequentially controlling the bladder and prostatic pedicles (Fig. 2B) using the Harmonic scalpel, the urethra is transected at the prostatic apex, and the anterior rectal wall is incised (Fig. 2C). Any remaining attachments are divided, the rectal remnant is excised, and the specimen is bagged and extracted (Fig. 2D). Adjacent segments of left and sigmoid colon are harvested for the conduit and colostomy, avoiding a bowel anastomosis. The ureters are anastomosed to the conduit, maintaining separation between the gastrointestinal and the urinary systems. The conduit and left end colostomy are matured (Fig. 3). The technique is performed entirely intracorporeally with specimen extraction through the anus, avoiding a large open incision. RESULTS: We present the case of a high-functioning (Eastern Cooperative Oncology Group performance status 1) 73-year-old man with metastatic castrate-resistant prostate cancer following failed primary brachytherapy. Despite a good systemic response to chemotherapy and complete androgen blockade, his prostate-specific antigen level continued to rise (to 33 ng/mL) because of an enlarging prostatic pelvic mass. He suffered from progressive local symptoms, including intractable pelvic pain, obstructive uropathy, and impending rectal obstruction. The indication for pelvic exenteration was local palliation. Total robotic time was 5.4 hours. The perioperative course was complicated by disseminated intravascular coagulation secondary to metastatic prostate cancer, which resulted in a transient ischemic attack. The disseminated intravascular coagulation resolved with blood product transfusion, and the patient recovered well without permanent disability. In-patient length of stay was 8 days. Complete local palliation was achieved until the patient's death from prostate cancer 5 months later. CONCLUSION: We demonstrate our step-by-step technique for robotic total pelvic exenteration with intracorporeal sigmoid conduit.

Robotic Radical Left Nephrectomy With Inferior Vena Cava Level III Thrombectomy.

INTRODUCTION AND OBJECTIVE: We present our robotic approach and technique to manage a large left renal tumor with inferior vena cava (IVC) Level III thrombus. The superior mesenteric artery crossing the left renal vein requires robotic docking from the left, for dissection of the left kidney followed by repositioning and re-docking the robot from the right side for dissection of the right renal vein, distal and proximal IVC, and the remaining left renal vein insertion into the IVC. METHODS: We present a 53-year-old man with a 10.9-cm left renal mass with IVC level III tumor thrombus. A robotic left radical nephrectomy with lymph node dissection was completed using 4 ports in a midline configuration. The dissection of the left renal vein was taken medially until the superior mesenteric artery. The patient was then repositioned in the right side flank position and the robot was re-docked using the previously placed midline ports. The right renal vein, distal and proximal IVC were then controlled using modified Rummel tourniquets. RESULTS: Operative time was 530 minutes which included patient positioning, robot re-docking. The patient did not require a blood transfusion. Hospital stay was 4 days. Final pathology showed pT3bNoM1 renal cell carcinoma, clear cell type grade 4 with necrosis, and focal rhabdoid features measuring 11 cm. The tumor invaded the renal sinus and the renal vein and was metastatic to the ipsilateral adrenal gland. Margins were negative. CONCLUSION: Herein we present a successful outcome of a left-sided robotic radical nephrectomy with IVC level III tumor thrombectomy.

Imaging strategy and outcome following partial nephrectomy.

OBJECTIVES: The aim of this study was to analyze the outcomes of surveillance after partial nephrectomy (PN) in a single institution and the relevance of imaging studies in detecting recurrence. MATERIAL AND METHODS: Retrospective study of 830 patients who underwent PN for localized renal cell carcinoma between 2007 and 2015 at a single institution. We studied the characteristics of recurrence according to pathological and clinical features and elaborated risk groups. The type and the total number of imaging studies performed during surveillance or until recurrence were evaluated. Outcomes of surveillance were analyzed. RESULTS: There were 48 patients (5.8%) diagnosed with recurrence during median 36 [21-52] months follow-up, including local recurrence in 18 patients (37.5%) and metastasis in 30 patients (62.5%). Totally, 17/18 patients (94.4%) with local recurrence and 26/30 patients (86.6%) with metastasis were diagnosed within the first 36 months after PN. When studying the recurrence rate, and time-to-recurrence, 2 risk groups emerged. Patients with pathological characteristics (tumors with pT1b or higher or high-grade tumor or positive surgical margin status) or patients with anatomical characteristics (high or moderate R.E.N.A.L. score) or both had high recurrence rate. Chest x-ray and abdominal ultrasound detected 7.7% and 3.4% of all recurrences, respectively, whereas computed tomography scan and magnetic resonance imaging scan detected the rest. Of the 48 patients diagnosed with recurrence, 44 (91.6%) were suitable for secondary active treatment (systemic, surgery, and radiotherapy) including 26 (54.2%) suitable for metastasectomy. The rate of relapse after secondary treatment was 43.5% (16.6% for the local recurrence group and 60.7% for metastasis group). CONCLUSION: Local recurrence emerges earlier than distant metastasis. Patients with any adverse pathological or anatomical features should be considered as high-risk group and followed closely in the first 36 months after PN with cross-sectional studies. Secondary active treatment is suitable for most patients, while surgical treatment fits fewer patients. Local recurrence is associated with increased rates of metastatic progression.

Robotic radical perineal cystectomy and extended pelvic lymphadenectomy: initial investigation using a purpose-built single-port robotic system.

OBJECTIVES: To assess the feasibility of radical perineal cystoprostatectomy using the latest generation purpose-built single-port robotic surgical system. MATERIALS AND METHODS: In two male cadavers the da Vinci® SP1098 Surgical System (Intuitive Surgical, Sunnyvale, CA, USA) was used to perform radical perineal cystoprostatectomy and bilateral extended pelvic lymph node dissection (ePLND). New features in this model include enhanced high-definition three-dimensional optics, improved instrument manoeuvrability, and a real-time instrument tracking and guidance system. The surgery was accomplished through a 3-cm perineal incision via a novel robotic single-port system, which accommodates three double-jointed articulating robotic instruments, an articulating camera, and an accessory laparoscopic instrument. The primary outcomes were technical feasibility, intraoperative complications, and total robotic operative time. RESULTS: The cases were completed successfully without conversion. There were no accidental punctures or lacerations. The robotic operative times were 197 and 202 min. CONCLUSIONS: In this preclinical model, robotic radical perineal cystoprostatectomy and ePLND was feasible using the SP1098 robotic platform. Further investigation is needed to assess the feasibility of urinary diversion using this novel approach and new technology.

Predictors of surgical quality for retroperitoneal sarcoma: Volume matters.

BACKGROUND AND OBJECTIVES: The volume-outcome relationship is well recognized. We sought to investigate this relationship in retroperitoneal sarcoma (RPS) surgery. METHODS: Non-metastatic RPS cases from 2004 to 2014 in the National Cancer Database were analyzed. Hospitals in the top 10th percentile for volume were defined as high-volume. Outcomes were selected a priori based on their known prognostic significance, including surgery use, R0/R1 resection, and R0 resection. Volume-outcome associations were assessed by univariate and multivariable analyses. RESULTS: Of 3141 RPS cases identified, 70.0% were managed surgically. Of these, 93.0% were R0/R1 resections, and 67.6% were R0 resections. Surgical management, R0/R1 resection, and R0 resection were each associated with improved overall survival (P < 0.001). Hospital volume was an independent predictor of surgical management, R0 resection, and R0/R1 resection. Patients treated at high-volume centers had 1.9-fold higher odds of undergoing surgical management (P < 0.001), 2.5-fold higher odds of receiving a R0/R1 resection (P = 0.026), and 1.8-fold higher odds of an R0 resection (P < 0.001). Academic setting predicted use of surgical management (P < 0.001) and R0/R1 resection (P = 0.015) but not R0 resection (P = 0.882). CONCLUSIONS: High-volume hospitals are significantly associated with surgery use and improved surgical outcomes. Consideration should be given to further centralization of RPS care.

Cytoreductive nephrectomy in the modern era: Predictors of use, morbidity, and survival.

INTRODUCTION: To determine tumour, patient, and provider factors associated with cytoreductive nephrectomy (CN) use and to identify those factors that predicted short-term and long-term surgical outcomes. METHODS: We performed a retrospective review (1998-2011) of the National Cancer Database, a U.S. population-based oncology outcomes database. The review included 36 549 patients with metastatic renal cell carcinoma (mRCC). We assessed predictors of CN use, length of stay (LOS), 30-day readmission, and 30-day mortality using multivariable logistic regression. The Cox proportional hazards model assessed predictors of overall survival (OS). RESULTS: Overall, 10 809 (29.6%) patients received CN, increasing from 15.2% to 36.1% over time. Private insurance (odds ratio [OR] 1.26; 95% confidence interval [CI] 1.16-1.37) and academic facilities (OR 1.83; 95% CI 1.68-1.99) were associated with receiving CN (p<0.0001). Charlson score ≥2 and older age group were less likely to undergo surgery (p<0.0001). Median LOS was five days (inter-quartile range [IQR] 3-7), while 30-day readmission and 30-day mortality were 5.3% and 3.3%, respectively. Undergoing CN (hazard ratio [HR] 0.48; 95% CI 0.44-0.52; p<0.0001) and treatment at academic centres (HR 0.88; 95% CI 0.81-0.95; p=0.001) were independently associated with improved OS. Limitation includes retrospective design with possible selection bias. CONCLUSIONS: Increased CN use continues in the modern era, with relatively low surgical morbidity. Further study is required to determine if the finding of lower all-cause mortality in patients treated at academic centres is due to improved care or unmeasured confounders.

Optimum outcome achievement in partial nephrectomy for T1 renal masses: a contemporary analysis of open and robot-assisted cases.

OBJECTIVES: To compare optimum outcome achievement in open partial nephrectomy (OPN) with that in robot-assisted partial nephrectomy (RAPN). PATIENTS AND METHODS: Using our institutional partial nephrectomy (PN) database, we reviewed 605 cases performed for unifocal clinical T1 renal masses in non-solitary kidneys between 2011 and 2015. Tetrafecta, which was defined as negative surgical margins, freedom from peri-operative complications, ≥80% renal function preservation, and no chronic kidney disease upstaging, was chosen as the composite optimum outcome. Factors associated with tetrafecta achievement were assessed using multivariable logistic regression, with adjustment for age, gender, race, Charlson comorbidity score, body mass index, chronic kidney disease, tumour size, tumour complexity and approach. RESULTS: The overall tetrafecta achievement rate was 38%. Negative margins, freedom from complications, and optimum functional preservation were achieved in 97.1%, 73.6% and 54.2% of cases, respectively. For T1a masses, the tetrafecta achievement rate was similar between approaches (P = 0.97), but for T1b masses, the robot-assisted approach achieved significantly higher tetrafecta rates (43.0% vs 21.3%; P < 0.01). On multivariable analysis, the robot-assisted approach had 2.6-fold higher odds of tetrafecta achievement than the open approach, primarily because of lower peri-operative morbidity, specifically related to wound complications. Positive surgical margin rates and renal function preservation were similar in the two approaches. CONCLUSIONS: Optimum outcomes are readily achieved regardless of PN approach. The robot-assisted approach may facilitate optimum outcome achievement for 4-7-cm masses by minimizing wound complications.

Excisional Precision Matters: Understanding the Influence of Excisional Volume Loss on Renal Function After Partial Nephrectomy.

Renal function after partial nephrectomy (PN) may depend on modifiable factors including ischemia time, excision of healthy parenchyma (excisional volume loss, EVL), and reconstructive methods. We retrospectively reviewed our institutional robotic PN database to identify the predictors of glomerular filtration rate (GFR) preservation (GFR-P) at 3-12 mo postoperatively, during which GFR decline plateaus. Baseline clinical, sociodemographic, and radiologic characteristics were captured. Univariate and multivariate (MV) linear regression analyses were performed and marginal effects were employed to examine the relative effect of EVL on renal function. A total of 647 patients who underwent robotic PN had GFR data at a median follow-up of 6 mo. On MV models, EVL was significantly correlated with GFR-P following log transformation (p=0.001). Each doubling of EVL caused a 1.5% decrease in GFR-P. Ischemia time and tumor complexity were not significantly associated with GFR-P. In summary, GFR-P after PN appears to be significantly associated with the excised volume of benign parenchyma. PATIENT SUMMARY: At a high-volume tertiary care center, we investigated the impact of surgical factors on kidney function after kidney cancer surgery. We found that the surgical precision with which the tumor is excised significantly impacts kidney function at 3-12 mo after surgery.

The Synergistic Influence of Ischemic Time and Surgical Precision on Acute Kidney Injury After Robotic Partial Nephrectomy.

OBJECTIVE: To examine the dynamic and potentially synergistic influence of warm ischemia time (WIT) and excisional volume loss (EVL) on predicted rates of postpartial acute kidney injury (AKI) across a range of tumor complexities, and to investigate whether these modifiable variables sensitize the kidney to each other's damaging influence. MATERIALS AND METHODS: We retrospectively reviewed 1245 patients between 2006 and 2016 with bilateral kidneys and enhancing renal masses in our single-institution robotic partial nephrectomy (PN) database. EVL was calculated as the difference between specimen and tumor volume based on pathologic measurements. Multivariate logistic regressions, followed by marginal effects, were run to examine the interaction of ischemia type, EVL, and radius, exophytic/endophytic properties, nearness of deepest tumor portion to collecting system or sinus, anterior/posterior and location relative to polar line score on rates of AKI. RESULTS: We found a significant interaction effect of WIT and log EVL on predicted AKI (P < .001). Each doubling of EVL caused a 4.03% and 8.46% increased probability of AKI for WIT of <25 and >25 minutes, respectively. At an EVL of >5.5 cm3, prolonged WIT had statistically greater odds of causing AKI. These predicted effects on AKI were amplified for increasing radius, exophytic/endophytic properties, nearness of deepest tumor portion to collecting system or sinus, anterior/posterior and location relative to polar line scores (P < .001). CONCLUSION: Although the adverse functional effects of WIT and parenchymal volume loss during PN have previously been described in isolation, our findings suggest that their influence on AKI is synergistic, especially in complex tumors. As such, additional attention should be given to limiting warm ischemia and maximizing surgical precision to avoid a "double hit" on postoperative renal function.