Hospital volume-outcome relationships for robot-assisted surgeries: a population-based analysis.

BACKGROUND: Associations between procedure volumes and outcomes can inform minimum volume standards and the regionalization of health services. Robot-assisted surgery continues to expand globally; however, data are limited regarding which hospitals should be using the technology. STUDY DESIGN: Using administrative health data for all residents of Ontario, Canada, this retrospective cohort study included adult patients who underwent a robot-assisted radical prostatectomy (RARP), total robotic hysterectomy (TRH), robot-assisted partial nephrectomy (RAPN), or robotic portal lobectomy using 4 arms (RPL-4) between January 2010 and September 2021. Associations between yearly hospital volumes and 90-day major complications were evaluated using multivariable logistic regression models adjusted for patient characteristics and clustering at the level of the hospital. RESULTS: A total of 10,879 patients were included, with 7567, 1776, 724, and 812 undergoing a RARP, TRH, RAPN, and RPL-4, respectively. Yearly hospital volume was not associated with 90-day complications for any procedure. Doubling of yearly volume was associated with a 17-min decrease in operative time for RARP (95% confidence interval [CI] - 23 to - 10), 8-min decrease for RAPN (95% CI - 14 to - 2), 24-min decrease for RPL-4 (95% CI - 29 to - 19), and no significant change for TRH (- 7 min; 95% CI - 17 to 3). CONCLUSION: The risk of 90-day major complications does not appear to be higher in low volume hospitals; however, they may not be as efficient with operating room utilization. Careful case selection may have contributed to the lack of an observed association between volumes and complications.

Hospital learning curves for robot-assisted surgeries: a population-based analysis.

BACKGROUND: Robot-assisted surgery has been rapidly adopted. It is important to define the learning curve to inform credentialling requirements, training programs, identify fast and slow learners, and protect patients. This study aimed to characterize the hospital learning curve for common robot-assisted procedures. STUDY DESIGN: This cohort study, using administrative health data for Ontario, Canada, included adult patients who underwent a robot-assisted radical prostatectomy (RARP), total robotic hysterectomy (TRH), robot-assisted partial nephrectomy (RAPN), or robotic portal lobectomy using four arms (RPL-4) between 2010 and 2021. The association between cumulative hospital volume of a robot-assisted procedure and major complications was evaluated using multivariable logistic models adjusted for patient characteristics and clustering at the hospital level. RESULTS: A total of 6814 patients were included, with 5230, 543, 465, and 576 patients in the RARP, TRH, RAPN, and RPL-4 cohorts, respectively. There was no association between cumulative hospital volume and major complications. Visual inspection of learning curves demonstrated a transient worsening of outcomes followed by subsequent improvements with experience. Operative time decreased for all procedures with increasing volume and reached plateaus after approximately 300 RARPs, 75 TRHs, and 150 RPL-4s. The odds of a prolonged length of stay decreased with increasing volume for patients undergoing a RARP (OR 0.87; 95% CI 0.82-0.92) or RPL-4 (OR 0.77; 95% CI 0.68-0.87). CONCLUSION: Hospitals may adopt robot-assisted surgery without significantly increasing the risk of major complications for patients early in the learning curve and with an expectation of increasing efficiency.

The evolving use of robotic surgery: a population-based analysis.

INTRODUCTION: Robotic surgery has integrated into the healthcare system despite limited evidence demonstrating its clinical benefit. Our objectives were (i) to describe secular trends and (ii) patient- and system-level determinants of the receipt of robotic as compared to open or laparoscopic surgery. METHODS: This population-based retrospective cohort study included adult patients who, between 2009 and 2018 in Ontario, Canada, underwent one of four commonly performed robotic procedures: radical prostatectomy, total hysterectomy, thoracic lobectomy, partial nephrectomy. Patients were categorized based on the surgical approach as robotic, open, or laparoscopic for each procedure. Multivariable regression models were used to estimate the temporal trend in robotic surgery use and associations of patient and system characteristics with the surgical approach. RESULTS: The cohort included 24,741 radical prostatectomy, 75,473 total hysterectomy, 18,252 thoracic lobectomy, and 4608 partial nephrectomy patients, of which 6.21% were robotic. After adjusting for patient and system characteristics, the rate of robotic surgery increased by 24% annually (RR 1.24, 95%CI 1.13-1.35): 13% (RR 1.13, 95%CI 1.11-1.16) for robotic radical prostatectomy, 9% (RR 1.09, 95%CI 1.05-1.13) for robotic total hysterectomy, 26% (RR 1.26, 95%CI 1.06-1.50) for thoracic lobectomy and 26% (RR 1.26, 95%CI 1.13-1.40) for partial nephrectomy. Lower comorbidity burden, earlier disease stage (among cancer cases), and early career surgeons with high case volume at a teaching hospital were consistently associated with the receipt of robotic surgery. CONCLUSION: The use of robotic surgery has increased. The study of the real-world clinical outcomes and associated costs is needed before further expanding use among additional providers and hospitals.

Adverse events following robotic surgery: population-based analysis.

BACKGROUND: Robotic surgery was integrated into some healthcare systems despite there being few well designed, real-world studies on safety or benefit. This study compared the safety of robotic with laparoscopic, thoracoscopic, and open approaches in common robotic procedures. METHODS: This was a population-based, retrospective study of all adults who underwent prostatectomy, hysterectomy, pulmonary lobectomy, or partial nephrectomy in Ontario, Canada, between 2008 and 2018. The primary outcome was 90-day total adverse events using propensity score overlap weights, and secondary outcomes were minor or major morbidity/adverse events. RESULTS: Data on 24 741 prostatectomy, 75 473 hysterectomy, 18 252 pulmonary lobectomy, and 6608 partial nephrectomy operations were included. Relative risks for total adverse events in robotic compared with open surgery were 0.80 (95 per cent c.i. 0.74 to 0.87) for radical prostatectomy, 0.44 (0.37 to 0.52) for hysterectomy, 0.53 (0.44 to 0.65) for pulmonary lobectomy, and 0.72 (0.54 to 0.97) for partial nephrectomy. Relative risks for total adverse events in robotic surgery compared with a laparoscopic/thoracoscopic approach were 0.94 (0.77 to 1.15), 1.00 (0.82 to 1.23), 1.01 (0.84 to 1.21), and 1.23 (0.82 to 1.84) respectively. CONCLUSION: The robotic approach is associated with fewer adverse events than an open approach but similar to a laparoscopic/thoracoscopic approach. The benefit of the robotic approach is related to the minimally-invasive approach rather than the platform itself.

Characterization of clinical human prostate cancer lesions using 3.0-T sodium MRI registered to Gleason-graded whole-mount histopathology.

BACKGROUND: Overtreatment of prostate cancer (PCa) is a healthcare issue. Development of noninvasive imaging tools for improved characterization of prostate lesions might reduce overtreatment. PURPOSE: To measure the distribution of tissue sodium concentration (TSC), proton T2 -weighted signal, and apparent diffusion coefficient (ADC) values in human PCa and to test the presence of a correlation between regional differences in imaging metrics and the Gleason grade of lesions determined from histopathology. STUDY TYPE: Cross-sectional. SUBJECTS: Ten men with biopsy-proven PCa. SEQUENCES/FIELD STRENGTH: Sodium, proton T2 -weighted, and diffusion-weighted MRI data were acquired using Broad-Band 3D-Fast-Gradient-Recalled, 3D Cube (Isotropic 3D-Fast-Turbo-Spin-Echo acquisition) and 2D Spin-Echo sequences, respectively, with a 3.0T MR scanner. ASSESSMENT: All imaging data were coregistered to Gleason-graded postprostatectomy histology, as the standard for prostate cancer lesion characterization. Regional TSC and T2 data were assessed using percent changes from healthy tissue of the same patient (denoted ΔTSC, ΔT2 ). STATISTICS: Differences in ΔTSC, ADC, and ΔT2 as a function of Gleason score were analyzed for each imaging contrast using a one-way analysis of variance or a nonparametric t-test. Correlations between imaging data measures and Gleason score were assessed using a Spearman's ranked correlation. RESULTS: Evaluation of the correlation of ΔTSC, ADC, and ΔT2 datasets with Gleason scoring revealed that only the correlation between ΔTSC and Gleason score was statistically significant (rs = 0.791, p < 0.01), whereas the correlations of ADC and ΔT2 with Gleason score were not (rs = -0.306, p = 0.079 and r s = -0.069, p = 0.699, respectively). In addition, all individual patients showed monotonically increasing ΔTSC with Gleason score. DATA CONCLUSION: The results of this preliminary study suggest that changes in TSC, assessed by sodium MRI, has utility as a noninvasive imaging assay to accurately characterize PCa lesions. Sodium MRI may provide useful complementary information on mpMRI, which may assist the decision-making of men choosing either active surveillance or treatment. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1409-1419.

Update on cryoablation for treatment of small renal mass: oncologic control, renal function preservation, and rate of complications.

Cryoablation has become a popular treatment option for the treatment of small renal masses (SRMs) in patients who are not ideal surgical candidates. This relatively new therapy continues to be studied in terms of its efficacy and safety. Intermediate- and long-term data published over the past year suggest comparable rates of oncological control for established extirpative options (partial and radical nephrectomy). Studies evaluating its safety profile show a decreased rate of major and minor complications, as compared with surgery. Cryoablation also offers excellent preservation of kidney function and is a viable treatment option in patients with preexisting renal compromise. The purpose of the present review is to summarize current literature on cryoablation therapy in the management of SRMs, with emphasis on studies published over the past year.

Active surveillance, radiofrequency ablation, or cryoablation for the nonsurgical management of a small renal mass: a cost-utility analysis.

BACKGROUND: Patients with a cortical small (≤4 cm) renal mass often are not candidates for or choose not to undergo surgery. The optimal management strategy for such patients is unclear. METHODS: A decision-analytic Markov model was developed from the perspective of a third party payer to compare the quality-adjusted life expectancy and lifetime costs for 67-year-old patients with a small renal mass undergoing premanagement decision biopsy, immediate percutaneous radiofrequency ablation or percutaneous cryoablation (without premanagement biopsy), or active surveillance with serial imaging and subsequent ablation if needed. RESULTS: The dominant strategy (most effective and least costly) was active surveillance with subsequent cryoablation if needed. On a quality-adjusted and discounted basis, immediate cryoablation resulted in a similar life expectancy (3 days fewer) but cost $3,010 more. This result was sensitive to the relative rate of progression to metastatic disease. Strategies that employed radiofrequency ablation had decreased quality-adjusted life expectancies (82-87 days fewer than the dominant strategy) and higher costs ($3,231-$6,398 more). CONCLUSIONS: Active surveillance with delayed percutaneous cryoablation, if needed, may be a safe and cost-effective alternative to immediate cryoablation. The uncertainty in the relative long-term rate of progression to metastatic disease in patients managed with active surveillance versus immediate cryoablation needs to be weighed against the higher cost of immediate cryoablation. A randomized trial is needed directly to evaluate the nonsurgical management of patients with a small renal mass, and could be limited to the most promising strategies identified in this analysis.

Succinate dehydrogenase kidney cancer: an aggressive example of the Warburg effect in cancer.

PURPOSE: Recently, a new renal cell cancer syndrome has been linked to germline mutation of multiple subunits (SDHB/C/D) of the Krebs cycle enzyme, succinate dehydrogenase. We report our experience with the diagnosis, evaluation and treatment of this novel form of hereditary kidney cancer. MATERIALS AND METHODS: Patients with suspected hereditary kidney cancer were enrolled on a National Cancer Institute institutional review board approved protocol to study inherited forms of kidney cancer. Individuals from families with germline SDHB, SDHC and SDHD mutations, and kidney cancer underwent comprehensive clinical and genetic evaluation. RESULTS: A total of 14 patients from 12 SDHB mutation families were evaluated. Patients presented with renal cell cancer at an early age (33 years, range 15 to 62), metastatic kidney cancer developed in 4 and some families had no manifestation other than kidney tumors. An additional family with 6 individuals found to have clear cell renal cell cancer that presented at a young average age (47 years, range 40 to 53) was identified with a germline SDHC mutation (R133X) Metastatic disease developed in 2 of these family members. A patient with a history of carotid body paragangliomas and an aggressive form of kidney cancer was evaluated from a family with a germline SDHD mutation. CONCLUSIONS: SDH mutation associated renal cell carcinoma can be an aggressive type of kidney cancer, especially in younger individuals. Although detection and management of early tumors is most often associated with a good outcome, based on our initial experience with these patients and our long-term experience with hereditary leiomyomatosis and renal cell carcinoma, we recommend careful surveillance of patients at risk for SDH mutation associated renal cell carcinoma and wide surgical excision of renal tumors.

Factors that impact the outcome of minimally invasive pyeloplasty: results of the Multi-institutional Laparoscopic and Robotic Pyeloplasty Collaborative Group.

PURPOSE: We compared laparoscopic and robotic pyeloplasty to identify factors associated with procedural efficacy. MATERIALS AND METHODS: We conducted a retrospective multicenter trial incorporating 865 cases from 15 centers. We collected perioperative data including anatomical and procedural factors. Failure was defined subjectively as pain that was unchanged or worse per medical records after surgery. Radiographic failure was defined as unchanged or worsening drainage on renal scans or worsening hydronephrosis on computerized tomography. Bivariate analyses were performed on all outcomes and multivariate analysis was used to assess factors associated with decreased freedom from secondary procedures. RESULTS: Of the cases 759 (274 laparoscopic pyeloplasties with a mean followup of 15 months and 465 robotic pyeloplasties with a mean followup of 11 months, p <0.001) had sufficient data. Laparoscopic pyeloplasty, previous endopyelotomy and intraoperative crossing vessels were associated with decreased freedom from secondary procedures on bivariate analysis, with a 2-year freedom from secondary procedures of 87% for laparoscopic pyeloplasty vs 95% for robotic pyeloplasty, 81% vs 93% for patients with vs without previous endopyelotomy and 88% vs 95% for patients with vs without intraoperative crossing vessels, respectively. However, on multivariate analysis only previous endopyelotomy (HR 4.35) and intraoperative crossing vessels (HR 2.73) significantly impacted freedom from secondary procedures. CONCLUSIONS: Laparoscopic and robotic pyeloplasty are highly effective in treating ureteropelvic junction obstruction. There was no difference in their abilities to render the patient free from secondary procedures on multivariate analysis. Previous endopyelotomy and intraoperative crossing vessels reduced freedom from secondary procedures.

Simple prostatectomy using the open and robotic approaches for lower urinary tract symptoms: A retrospective, case-control series.

INTRODUCTION: We aimed to assess the outcome of our series of simple prostatectomy at our institution using the open simple prostatectomy (OSP) and robotic-assisted simple prostatectomy (RASP) approaches. METHODS: We conducted a retrospective chart review of men who underwent OSP and RASP at Western University, in London, ON. Preoperative, intraoperative, and postoperative data were collected and analyzed. RESULTS: From 2012-2020, 29 men underwent a simple prostatectomy at our institution. Eight patients underwent an OSP and 21 patients underwent a RASP. The median age was 69 years. Preoperative median prostate volume was 153 cm³ (range 80-432). The surgical indications were failed medical treatment, urinary retention, hydronephrosis, cystolithiasis, and recurrent hematuria. The median operative time was 137.5 minutes in OSP and 185 minutes in RASP (p=0.04). Median estimated blood loss was 2300 ml (range 600-4000) and 100 ml (range 50-400) in the open and robotic procedures, respectively (p=0.4). The mean length of hospital stay was shorter in the RASP group, one day vs. three days (z=4.152, p&lt;0.005). Perioperative complication rates were significantly lower in the group undergoing RASP, with no complications recorded in this group (p=0.004). Both groups demonstrated excellent functional results, with most patients reporting complete urinary continence (p=0.8). CONCLUSIONS: We report very good perioperative outcomes, with a minimal risk profile and excellent functional results, leading to marked improvement in patients' symptoms at followup after both the OSP and RASP approaches. RASP was associated with a shorter length of hospital stay, decreased blood loss, and a lower complication rate.

Cumulative summation graphs are a useful tool for monitoring positive surgical margin rates in robot-assisted radical prostatectomy.

OBJECTIVE: • To explore the usefulness of cumulative summation (CUSUM) graphs for monitoring positive surgical margin (PSM) rates during a surgeon's transition from open to robot-assisted radical prostatectomy (RARP). PATIENTS AND METHODS: • Data were prospectively collected from patients undergoing RARP by a single surgeon. • Preoperatively all patients were either low or moderate risk under the D'Amico classification system. • A CUSUM graph was charted retrospectively to analyse the PSM rate in patients undergoing RARP for pathological stage T2 (pT2) disease. • Acceptable and unacceptable PSM rates were set at 10% and 15% respectively. RESULTS: • From a cohort of 226 patients, 158 patients with pT2 disease were selected. The mean (range) age of these patients was 59.2 (39-73) years, the median (range) Gleason score was 6 (4-9), the mean (range) PSA was 6.43 (0.52-17.5) ng/mL and the mean (range) prostate volume was 44 (18-120) cm(3). In all, 21 patients had PSMs (13%). • CUSUM graphs were produced and clearly demonstrated the change in PSM rate over time. CONCLUSION: • CUSUM graphs are a novel and useful visual representation of the learning curve for surgeons. • PSM rates in patients with pT2 disease are a good outcome to monitor using CUSUM graphs as they are binary and lack the confounding factors associated with other outcomes such as continence and erectile dysfunction. • We advocate the use of CUSUM graphs as a method of quality assurance with the introduction of a robotics programme.

Robot-assisted laparoscopic prostatectomy in patients with preexisting three-piece inflatable penile prosthesis.

INTRODUCTION: Robotic-assisted laparoscopic radical prostatectomy (RARP) is becoming the preferred surgical treatment option for management of organ-confined prostate cancer. Although not a contraindication, previous pelvic surgery can make RARP challenging. Presence of a three-piece inflatable penile prosthesis, with a perivesical pelvic reservoir, has the potential to induce steric hindrance making RARP difficult. AIM: The main purpose of this publication is to report our experience with RARP in patients with previously inserted three-piece inflatable penile prostheses. METHODS: Two patients with previously inserted AMS 700 penile prosthesis and with organ-confined, biopsy proven adenocarcinoma of the prostate underwent RARP. We describe intraoperative findings, surgical technique, oncologic and functional outcomes. RESULTS: Both patients underwent safe and successful RARP with out any complications. Surgical margins were not affected with pelvic reservoir-sparing technique. In both patients, the penile prosthesis remained functional postoperatively. CONCLUSIONS: RARP can be safely performed in patients with previously inserted three-piece inflatable penile prosthesis. Nontraumatic handling of the pelvic reservoir is mandatory to preserve prosthesis' integrity.

Thermal ablation of small renal masses: intermediate outcomes from a Canadian center.

INTRODUCTION: Cryoablation (CA) and radio frequency ablation (RFA) are nephron sparing procedures that destroy renal tissue in situ rather than by surgical removal. Both thermal ablative techniques are advocated in select patient population with a small renal mass and multiple comorbidities which may preclude major surgery. Unfortunately long term oncologic outcomes of these procedures are unknown. MATERIALS AND METHODS: We report oncologic outcomes following CA and RFA in patients with small renal masses, from a single center, during a 48 month follow up period. Thirty patients underwent thermal ablation of a small renal mass, 7 with RFA and 23 with CA. RESULTS: Median tumor size on preoperative CT was 2.6 cm ± 0.87 cm. Four patients experienced a loco-regional treatment failure and underwent subsequent radical nephrectomy. Two patients were diagnosed with metastatic renal cell cancer in the follow up period. Six patients died during the follow up period, five from unrelated cause and one from metastatic RCC (overall survival 80%, RCC-specific survival 96%). CONCLUSIONS: This study demonstrates low RCC recurrence rates and in combination with previously published reports supports the effectiveness of thermal ablation therapy as primary therapeutic option in a very specific patient population.

Metal fatigue causing cystoscope rupture during bladder neck incision.

The modern cystoscope is the result of the advancement in technology in numerous areas and is an invaluable tool that allows the urologist to perform a number of diagnostic and therapeutic procedures. Although various degrees of endoscope failure have been widely reported, instrument breakage that leads to a foreign body has not. While performing a bladder neck stricture incision for a 72-year-old male patient with a previous radical prostatectomy for prostate cancer and a resulting bladder neck stricture, we documented a major 17-French cystoscope malfunction and a resulting foreign body that was retrieved from the bladder using a 22-French scope and alligator forceps.

Potential Pitfalls in Pre-implantation Genetic Diagnosis in a Patient with Tuberous Sclerosis and Isolated Mosaicism for a TSC2 Variant in Renal Tissue.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that displays a wide spectrum of clinical manifestations, often affecting multiple organs including the kidneys, brain, lungs, and skin. A pathogenic mutation in either the TSC1 or TSC2 gene can be detected in almost 85% of the cases, with mosaicism accounting for about half of the remaining cases. We report a case of TSC diagnosed clinically, requesting genetic counselling regarding reproductive risks. No mutation was identified on initial testing of peripheral blood; however, mosaicism for a likely pathogenic frameshift variant in TSC2 was detected at a level of 15% in renal angiomyolipoma tissue. Despite widespread clinical manifestations of TCS, this variant was not detected in skin fibroblasts or saliva, raising the possibility this is an isolated somatic mutation in renal tissue with the underlying germline mutation not yet identified. This case highlights the difficulties when counselling patients with mosaicism regarding their reproductive risks and prenatal diagnostic options.

Case report - Primary renal echinococcal infection.

Renal echinococcal infection is an uncommonly encountered infection in North America but is endemic in many parts of the world. With increasing migration, it is conceivable that practicing Canadian physicians will see more patients presenting at various stages of infection. Herein, we describe an unusual presentation of primary renal echinococcal infection and describe current diagnostic, as well as medical and surgical management strategies.

Ureteral Stent Microbiota Is Associated with Patient Comorbidities but Not Antibiotic Exposure.

Ureteral stents are commonly used to prevent urinary obstruction but can become colonized by bacteria and encrusted, leading to clinical complications. Despite recent discovery and characterization of the healthy urinary microbiota, stent-associated bacteria and their impact on encrustation are largely underexplored. We profile the microbiota of patients with typical short-term stents, as well as over 30 atypical cases (all with paired mid-stream urine) from 241 patients. Indwelling time, age, and various patient comorbidities correlate with alterations to the stent microbiota composition, whereas antibiotic exposure, urinary tract infection (UTI), and stent placement method do not. The stent microbiota most likely originates from adhesion of resident urinary microbes but subsequently diverges to a distinct, reproducible population, thereby negating the urine as a biomarker for stent encrustation or microbiota. Urological practice should reconsider standalone prophylactic antibiotics in favor of tailored therapies based on patient comorbidities in efforts to minimize bacterial burden, encrustation, and complications of ureteral stents.

Small Renal Mass Surveillance: Histology-specific Growth Rates in a Biopsy-characterized Cohort.

BACKGROUND: Most reports of active surveillance (AS) of small renal masses (SRMs) lack biopsy confirmation, and therefore include benign tumors and different subtypes of renal cell carcinoma (RCC). OBJECTIVE: We compared the growth rates and progression of different histologic subtypes of RCC SRMs (SRMRCC) in the largest cohort of patients with biopsy-characterized SRMs on AS. DESIGN, SETTING, AND PARTICIPANTS: Data from patients in a multicenter Canadian trial and a Princess Margaret cohort were combined to include 136 biopsy-proven SRMRCC lesions managed by AS, with treatment deferred until progression or patient/surgeon decision. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Growth curves were estimated from serial tumor size measures. Tumor progression was defined by sustained size ≥4 cm or volume doubling within 1 yr. RESULTS AND LIMITATIONS: Median follow-up for patients who remained on AS was 5.8 yr (interquartile range 3.4-7.5 yr). Clear cell RCC SRMs (SRMccRCC) grew faster than papillary type 1 SRMs (0.25 and 0.02 cm/yr on average, respectively, p = 0.0003). Overall, 60 SRMRCC lesions progressed: 49 (82%) by rapid growth (volume doubling), seven (12%) increasing to ≥4 cm, and four (6.7%) by both criteria. Six patients developed metastases, and all were of clear cell RCC histology. Limitations include the use of different imaging modalities and a lack of central imaging review. CONCLUSIONS: Tumor growth varies between histologic subtypes of SRMRCC and among SRMccRCC, which likely reflects individual host and tumor biology. Without validated biomarkers that predict this variation, initial follow-up of histologically characterized SRMs can inform personalized treatment for patients on AS. PATIENT SUMMARY: Many small kidney cancers are suitable for surveillance and can be monitored over time for change. We demonstrate that different types of kidney cancers grow at different rates and are at different risks of progression. These results may guide better personalized treatment.

Use of cumulative summation (CUSUM) as a tool for early feedback and monitoring in robot-assisted radical prostatectomy outcomes and performance.

INTRODUCTION: Today's surgical practice has evolved, with increasing emphasis on quality assurance. Many forms of quality-control monitoring have been suggested, but they are often impractical or difficult to implement. Cumulative summation (CUSUM) is a simple method to provide visual feedback before significant quality issues arise. We present our initial use and practical application of CUSUM in a surgical practice. METHODS: A retrospective analysis was applied to a prospectively collected database of 577 sequential patients who have undergone robot-assisted radical prostatectomy from a single surgeon over a 10-year period. Outcome measures were analyzed with CUSUM, which included a composite complication score, continence rates, length of hospital stay, biochemical recurrence, and need for adjuvant radiation. If any outcomes were out of control, they would cross the CUSUM failure line. RESULTS: CUSUM chart-plotting for incontinence demonstrated an initial upward slope followed by trending to a new safety limit. Additionally, outcomes in complications and biochemical recurrence did not reach the established safety boundaries. Length of stay and radiation outcomes did initially cross the safety line, but were improved over time. CONCLUSIONS: The use of CUSUM in clinical practice can fulfill the need for quality assurance. CUSUM plotting in our practice reflected the initial learning curve, followed by ongoing maintenance and improvement in performance. These changes were consistent with the implementation of changes in surgical techniques. Although this tool was used retrospectively, this strengthens our argument to implement the tool prospectively and assess real-time refinement of surgeon skill. We have demonstrated that CUSUM can be appropriately used to assure quality control in a surgical practice.

Hydro-Jet Dissection of the Cavernous Nerves Preserves Erection Function in a Radical Prostatectomy Animal Model.

BACKGROUND: Postoperative erectile dysfunction (ED) remains a prevalent consequence of radical prostatectomy (RP) that significantly impacts patient quality of life. Water-jet technology is widely used for dissection in neurosurgical procedures but novel to urologic surgery. AIM: To establish the impact of hydro-jet dissection (HJD) of the cavernous nerves (CN) on postoperative erectile function in an animal model of RP-induced ED. METHODS: 32 male Sprague-Dawley rats were randomized to 4 groups: Sham surgery (n = 8), bilateral HJD of CN (n = 8), blunt CN injury (n = 8), or stretch CN injury (n = 8). After 4 weeks, erectile function was assessed by measuring intracavernous pressure (ICP), and penile tissues were harvested for immunohistologic studies. MAIN OUTCOME MEASURE: The peak ICP and the area under the curve were calculated for each group. Immunohistologic studies were performed for α-smooth muscle actin and neuronal nitric oxide synthase on cross-sections of penile tissue. RESULTS: Rats in the HJD group demonstrate a significantly higher mean peak ICP and area under the curve compared with both CN injury groups (P = .001). Postoperative erectile function in the HJD group returned to baseline function. Preservation of α-smooth muscle actin and neuronal nitric oxide synthase was observed in the HJD group compared with the other surgical trauma groups. CLINICAL IMPLICATIONS: Hydro-jet dissection used in an RP animal model maintains erectile function and offers a potential benefit that warrants further human studies. STRENGTHS & LIMITATIONS: This is a novel animal study comparing a new technology to established CN dissection techniques. This study uses an animal model, which may not completely translate to post-RP ED in humans. CONCLUSION: Hydro-jet dissection of the CN during RP in an animal model is associated with significantly better postoperative erectile function when compared with other CN injury. Clinical studies are needed to further investigate the putative benefit of HJD on erectile function in patients undergoing RP. Campbell JD, Alenezi H, DeYoung LX, et al. Hydrojet Dissection of the Cavernous Nerves Preserves Erection Function in a Radical Prostatectomy Animal Model. Sex Med 2019;7:104-110.