Predictors of Same-Day Discharge after Single-Port Transvesical Enucleation of the Prostate (STEP).

OBJECTIVES: To determine the rate of outpatient cases and identify predictors for same-day discharge (SDD) after single-port transvesical enucleation of the prostate (STEP). METHODS: Retrospective analysis of all consecutive STEP cases performed at a single center by three surgeons from February 2019 to October 2023. The cohort was categorized into SDD cases (<8 hours until discharge) and inpatient cases. Group comparisons were made and logistic regression was used to identify predictors of SDD. RESULTS: A total of 152 STEP cases were performed successfully without additional ports or conversions. Fifty-two patients were pre-planned admissions, leaving 100 planned outpatient cases, of which 86% were discharged on the same day (median length of stay of 4.7 hours). Comparing the groups, inpatient cases were older, had higher Charlson Comorbidity Index (CCI) scores, higher estimated blood loss (EBL) during surgery, and more intraoperative complications than SDD patients. Univariate logistic regression identified age and CCI as the predictors associated with SDD after STEP. Notably, there were no major postoperative complications or readmissions in either group. CONCLUSIONS: In our four-year experience with STEP, lower age and CCI score were significant predictors of SDD. The comprehensive evaluation criteria for discharge foster a safe recovery at home, coupled with a 0% rate of major postoperative complications and readmissions. These findings underscore the safety and efficacy of STEP, guiding patient counseling and surgeon expectations.

Perioperative Complications of Single-Port and Multiport Robotic Radical Prostatectomy: A Single Institutional Comparison Analysis.

Background: Following its introduction in 2018, the Single-Port (SP) robotic platform has been increasingly utilized for various approaches of robotic radical prostatectomy (RARP). Despite the demonstrable benefits in enhancing postoperative outcomes, there has been limited evidence on its perioperative morbidity, especially when compared to the gold-standard multiport (MP). This study sought to compare the perioperative morbidity between SP and MP-RARP. Methods: A retrospective review was performed on 911 patients who underwent RARP between January 2015 and May 2023. At our institution, SP-RARP has been performed since October 2018 with Extraperitoneal and Transvesical (TV) techniques. To reduce the risk of selection bias, only MP-RARP cases performed before October 2018 were included. Baseline clinicodemographic and perioperative parameters were collected. Perioperative complications were classified in accordance to the Clavien-Dindo system with postoperative complications and readmission reported within 90 days of surgery. Statistical analysis was performed with R Packages for Statistical Computing with descriptive statistics as presented. Results: Of the 484 SP and 322 MP-RARP cases included in our analysis, one intraoperative complication was reported, which pertained to a small enterotomy during TV SP-RARP. Postoperative complications were identified in 14.5% and 14.6% of SP and MP-RARP cases (p = 0.989), respectively. Major complication represents 4.1% of the SP and 3.4% of MP cohorts. The 90-day rates of hospital readmission following SP and MP-RARP were 5.6% and 4.9%, respectively (p = 0.717). Limitations of this study included the retrospective single surgeon, single institution nature of our series that also included the early learning curve experience associated with the novel SP platform. Conclusion: This comparative study provided evidence highlighting the low rates of perioperative complication and readmission following SP-RARP that were comparable to the Transperitoneal MP approach. The low morbidity associated with SP-RARP supports its wider application as an addition to the contemporary minimally invasive surgical armamentariums for prostate cancer.

Single-port Transvesical Robot-Assisted Simple Prostatectomy: Surgical Technique and Clinical Outcomes.

BACKGROUND: Surgical management of large prostatic adenomas can be performed via open, endoscopic, or robotic approaches. A low-profile single-port (SP) robot was built to work in confined areas (ie, the bladder) and regionalize surgery. OBJECTIVE: To describe the novel SP transvesical (TV) robot-assisted simple prostatectomy (RASP) and report clinical outcomes. DESIGN, SETTING, AND PARTICIPANTS: SP TV RASP cases were performed in an academic hospital by two surgeons from 2019 to 2023. A total of 117 cases were performed, and data from patients with at least 12 mo of follow-up were analyzed. The inclusion criterion was severe obstructive urinary symptoms or catheter-dependent urinary retention due to large prostates with volume >80 ml. SURGICAL PROCEDURE: The procedure consisted of two main steps through a single 3-cm suprapubic incision: first, enucleation of the adenoma, and second, a 360° bladder mucosal flap reconstruction. No drains or continuous bladder irrigation was used routinely. MEASUREMENTS: Intraoperative parameters, pre- and postoperative uroflowmetry, and 1-yr clinical outcomes were assessed. We used descriptive statistics to analyze the data. RESULTS AND LIMITATIONS: All procedures were completed successfully without additional ports or conversions. The median console time and estimated blood loss were 107 min and 100 ml, respectively. Transfusion rate was 0%. Intraoperative complications included two suspected air emboli attributed to high insufflation pressures. There were no major postoperative complications. In total, 95.8% were discharged within the first 24 h, with a median length of stay and pain score of 5 h and 3/10, respectively. There was persistent improvement in the median International Prostate Symptom Score and flow rate after 1 yr. The median Sexual Score Inventory for Men score was 20 at 12 mo. Our study is limited by its retrospective nature and cohort size. CONCLUSIONS: SP TV RASP is a feasible alternative for the management of severe benign prostatic hyperplasia that promotes fast recovery and demonstrates 1-yr improvement in urinary function. PATIENT SUMMARY: Single-port transvesical robot-assisted simple prostatectomy is a minimally invasive alternative for the treatment of large benign prostatic growth. A single robotic arm goes through a small incision in the skin and bladder to extract the obstructive prostatic tissue. Afterward, reconstruction of the area is done to decrease bleeding and improve postoperative symptoms. We found that patients recover quickly and have excellent clinical results with a low risk of complications.

Saline-assisted fascial exposure (SAFE) technique to improve nerve-sparing in robot-assisted laparoscopic radical prostatectomy.

OBJECTIVE: To provide a summary of our initial experience and assess the impact of the Saline-Assisted Fascial Exposure (SAFE) technique on erectile function (EF), urinary continence, and oncological outcomes after Robot-Assisted Laparoscopic Radical Prostatectomy (RALP). PATIENTS AND METHODS: From January 2021 to July 2022, we included patients with a baseline Sexual Health Inventory for Men (SHIM) score of ≥17 and a high probability of extracapsular extension (ECE), ranging from 21% to 73%, as per the Martini et al. nomogram. A propensity score matching was carried out at a ratio of 1:2 between patients who underwent RALP + SAFE (33) and RALP alone (66). The descriptive statistical analysis is presented. The SAFE technique was performed using two approaches, transrectal guided by micro-ultrasound or transperitoneal. Its principle entails a low-pressure injection of saline solution in the periprostatic fascia to achieve an atraumatic dissection of the neural hammock. Potency was defined as a SHIM score of ≥17 and continence as no pads per day. RESULTS: At follow-up intervals of 6, 13, 26, and 52 weeks, the SHIM score differed significantly between the two groups, favouring the RALP + SAFE (P = 0.01, P < 0.001, P < 0.001, and P = 0.01, respectively). These results remained significant when the mean SHIM score was assessed. As shown by the cumulative incidence curve, EF rates were higher in the RALP + SAFE compared to the RALP alone group (log-rank P < 0.001). The baseline SHIM and use of the SAFE technique were independent predictors of EF recovery. CONCLUSIONS: The use of the SAFE technique led to better SHIM scores at 6, 13, 26, and 52 weeks after RALP in patients at high risk of ECE who underwent a partial NS procedure.

Defining the Role of Large Language Models in Urologic Care and Research.

Large language models such as ChatGPT are poised to transform health care. We envision them being used in the future in urology, albeit with appropriate supervision, to educate patients, guide clinicians and scientists, and automate complex tasks.

Predictors of Early Continence After Single-port Transvesical Robot-assisted Radical Prostatectomy.

OBJECTIVE: To identify the factors associated with a short time of return to continence. METHODS: We analyzed the first 110 SP TV RARP consecutive cases performed by one surgeon from 2020 to 2022. Continence was defined as zero to one safety pad. Two statistical analyses were done. First, patients were divided: group A (n = 62) included individuals who achieved continence within the initial week postcatheter removal; group B (n = 48) rest of the patients. Descriptive statistics were compared, followed by logistic regression for independent variables. Second, time to continence was analyzed as a continuous variable employing linear regression. The primary outcomes were the independent variables significantly associated with a short time to continence. RESULTS: All cases were completed successfully, without additional ports or conversions. Median urinary catheter duration and time to continence were 3 and 3.5days, respectively. Patients achieving continence within 1week significantly presented with fewer preoperative urinary tract symptoms, lower prostate-specific antigen levels, and had smaller specimen weights postoperatively. Multivariable logistic regression established low specimen weight as the sole significant factor (P = .04). Furthermore, linear regression demonstrated that alterations in independent variables accounted for 12.7% of the variance in time to continence (P = .62). CONCLUSION: The regionalization of surgery to the bladder employing a retropubic space-sparing extraperitoneal approach during SP TV RARP contributes to a fast return to continence. According to our model, the factors that significantly predict a shorter time to continence include lower preoperative International Prostate Symptom Score, prostate-specific antigen, and postoperative specimen weight.

AI-powered real-time annotations during urologic surgery: The future of training and quality metrics.

INTRODUCTION AND OBJECTIVE: Real-time artificial intelligence (AI) annotation of the surgical field has the potential to automatically extract information from surgical videos, helping to create a robust surgical atlas. This content can be used for surgical education and qualitative initiatives. We demonstrate the first use of AI in urologic robotic surgery to capture live surgical video and annotate key surgical steps and safety milestones in real-time. SUMMARY BACKGROUND DATA: While AI models possess the capability to generate automated annotations based on a collection of video images, the real-time implementation of such technology in urological robotic surgery to aid surgeon and training staff it is still pending to be studied. METHODS: We conducted an educational symposium, which broadcasted 2 live procedures, a robotic-assisted radical prostatectomy (RARP) and a robotic-assisted partial nephrectomy (RAPN). A surgical AI platform system (Theator, Palo Alto, CA) generated real-time annotations and identified operative safety milestones. This was achieved through trained algorithms, conventional video recognition, and novel Video Transfer Network technology which captures clips in full context, enabling automatic recognition and surgical mapping in real-time. RESULTS: Real-time AI annotations for procedure #1, RARP, are found in Table 1. The safety milestone annotations included the apical safety maneuver and deliberate views of structures such as the external iliac vessels and the obturator nerve. Real-time AI annotations for procedure #2, RAPN, are found in Table 1. Safety milestones included deliberate views of structures such as the gonadal vessels and the ureter. AI annotated surgical events included intraoperative ultrasound, temporary clip application and removal, hemostatic powder application, and notable hemorrhage. CONCLUSIONS: For the first time, surgical intelligence successfully showcased real-time AI annotations of 2 separate urologic robotic procedures during a live telecast. These annotations may provide the technological framework for send automatic notifications to clinical or operational stakeholders. This technology is a first step in real-time intraoperative decision support, leveraging big data to improve the quality of surgical care, potentially improve surgical outcomes, and support training and education.

Robot-assisted simple prostatectomy for prostates greater than 100 g.

PURPOSE: Efforts are ongoing to treat severe benign prostatic hyperplasia as traditional endoscopic treatment options are often difficult to perform and associated with significant complications. This manuscript highlights our initial experience of robot-assisted simple prostatectomy [RASP] with minimum a year follow-up. We also compared our outcomes with published literature. METHODS: After an Institution Review Board approval, we gathered data of 50 cases of RASP between Jan 2014 and May 2021. Patients with prostate volume > 100 cc [calculated from magnetic resonance imaging (MRI)] and prostate biopsy confirmed benign prostate were candidates for RASP. Patients underwent RASP via transperitoneal route either by suprapubic or trans-vesical approach. Preoperative demographics, peri-operative parameters and post-operative parameters such as hospital stay, catheter removal, urinary continence and uroflow were recorded in standard database and presented as descriptive statistics. RESULTS: Patients presented with a baseline median International Prostate Symptom Score (IPSS) of 23 (inter-quartile range (IQR) 21,25) and a median PSA of 7.7 ng/ml (IQR 6.4,8.7). Median preoperative prostate volume was 167 ml (IQR, 136,198 ml). Median console time was 118 min, and median estimated blood loss was 148 ml (IQR 130, 167 ml). None of our cohort needed intraoperative transfusion, conversion to open surgery or developed any complications. Median time to Foley removal was 10 days (IQR 8,12). Significant drop in the IPSS score and improvement in Qmax was noted over the period of follow-up. CONCLUSION: RASP is associated with considerable improvements in urinary symptoms. However, comparative studies with endoscopic treatment options of large prostatic adenomas are warranted and ideally include cost analysis of different procedures.

Side-specific, Microultrasound-based Nomogram for the Prediction of Extracapsular Extension in Prostate Cancer.

Background: Prediction of extracapsular extension (ECE) is essential to achieve a balance between oncologic resection and neural tissue preservation. Microultrasound (MUS) is an attractive alternative to multiparametric magnetic resonance imaging (mpMRI) in the staging scenario. Objective: To create a side-specific nomogram integrating clinicopathologic parameters and MUS findings to predict ipsilateral ECE and guide nerve sparing. Design setting and participants: Prospective data were collected from consecutive patients who underwent robotic-assisted radical prostatectomy from June 2021 to May 2022 and had preoperative MUS and mpMRI. A total of 391 patients and 612 lobes were included in the analysis. Outcome measurements and statistical analysis: ECE on surgical pathology was the primary outcome. Multivariate regression analyses were carried out to identify predictors for ECE. The resultant multivariable model's performance was visualized using the receiver-operating characteristic curve. A nomogram was developed based on the coefficients of the logit function for the MUS-based model. A decision curve analysis (DCA) was performed to assess clinical utility. Results and limitations: The areas under the receiver-operating characteristic curve (AUCs) of the MUS-based model were 81.4% and 80.9% (95% confidence interval [CI] 75.6, 84.6) after internal validation. The AUC of the mpMRI-model was also 80.9% (95% CI 77.2, 85.7). The DCA demonstrated the net clinical benefit of the MUS-based nomogram and its superiority compared with MUS and MRI alone for detecting ECE. Limitations of our study included its sample size and moderate inter-reader agreement. Conclusions: We developed a side-specific nomogram to predict ECE based on clinicopathologic variables and MUS findings. Its performance was comparable with that of a mpMRI-based model. External validation and prospective trials are required to corroborate our results. Patient summary: The integration of clinical parameters and microultrasound can predict extracapsular extension with similar results to models based on magnetic resonance imaging findings. This can be useful for tailoring the preservation of nerves during surgery.

Technical Tips in Managing Large Median Lobes During Robot-assisted Radical Prostatectomy.

Prostate cancer surgeons are commonly faced by a technically challenging situation dealing with prostate cancer having large median lobes. Patients with large median lobes often have larger prostates, which makes it difficult to visualize anatomical planes during robot-assisted radical prostatectomy (RARP). Herein, we described our experience in dealing with large median lobes during RARP. We have focused on technical tips to avoid complications and facilitate a smooth procedure in patients with large median lobes during RARP. A total of 2671 patients who underwent RARP were divided into two groups based on the presence or absence of a protruded median lobe (PML): group A (2411 patients without a PML) and group B (260 patients with a PML). All patients underwent preoperative magnetic resonance imaging and final intraoperative confirmation for the presence of a PML. Pre-, intra-, and postoperative parameters were compared in two groups using the Student t test and two-proportion t test as appropriate. Patients in group B have statistically significantly higher median prostate-specific antigen (PSA; 7.7 vs 5.8 ng/dl), PSA density (0.17 vs 0.09), and International Prostate Symptom Score (19.5 vs 7.2); longer median console time (114 vs 134 min) and surgery time (145 vs 170 min); and higher blood loss (150 vs 175 ml) than those in group A. There were no statistically significant differences in pathological stages (T2, T3; 87%, 13% vs 88%, 12%) and rates of positive surgical margins (7% vs 8.5%) between groups A and B. Single-center and retrospective design was the major limitation of our study. We conclude that understanding the key steps to facilitate bladder neck dissection is vital to avoid serious intraoperative events and to maximize outcomes. Patient summary: In this report, we looked at our robotic radical prostatectomy cohort with large median lobes. We found that surgery in these patients requires more time and blood loss, but similar cancer control. We conclude that following the key steps are important to avoid complications.

The Mount Sinai Prebiopsy Risk Calculator for Predicting any Prostate Cancer and Clinically Significant Prostate Cancer: Development of a Risk Predictive Tool and Validation with Advanced Neural Networking, Prostate Magnetic Resonance Imaging Outcome Database, and European Randomized Study of Screening for Prostate Cancer Risk Calculator.

Background: The European Association of Urology guidelines recommend the use of imaging, biomarkers, and risk calculators in men at risk of prostate cancer. Risk predictive calculators that combine multiparametric magnetic resonance imaging with prebiopsy variables aid as an individualized decision-making tool for patients at risk of prostate cancer, and advanced neural networking increases reliability of these tools. Objective: To develop a comprehensive risk predictive online web-based tool using magnetic resonance imaging (MRI) and clinical data, to predict the risk of any prostate cancer (PCa) and clinically significant PCa (csPCa) applicable to biopsy-naïve men, men with a prior negative biopsy, men with prior positive low-grade cancer, and men with negative MRI. Design setting and participants: Institutional review board-approved prospective data of 1902 men undergoing biopsy from October 2013 to September 2021 at Mount Sinai were collected. Outcome measurements and statistical analysis: Univariable and multivariable analyses were used to evaluate clinical variables such as age, race, digital rectal examination, family history, prostate-specific antigen (PSA), biopsy status, Prostate Imaging Reporting and Data System score, and prostate volume, which emerged as predictors for any PCa and csPCa. Binary logistic regression was performed to study the probability. Validation was performed with advanced neural networking (ANN), multi-institutional European cohort (Prostate MRI Outcome Database [PROMOD]), and European Randomized Study of Screening for Prostate Cancer Risk Calculator (ERSPC RC) 3/4. Results and limitations: Overall, 2363 biopsies had complete clinical information, with 57.98% any cancer and 31.40% csPCa. The prediction model was significantly associated with both any PCa and csPCa having an area under the curve (AUC) of 81.9% including clinical data. The AUC for external validation was calculated in PROMOD, ERSPC RC, and ANN for any PCa (0.82 vs 0.70 vs 0.90) and csPCa (0.82 vs 0.78 vs 0.92), respectively. This study is limited by its retrospective design and overestimation of csPCa in the PROMOD cohort. Conclusions: The Mount Sinai Prebiopsy Risk Calculator combines PSA, imaging and clinical data to predict the risk of any PCa and csPCa for all patient settings. With accurate validation results in a large European cohort, ERSPC RC, and ANN, it exhibits its efficiency and applicability in a more generalized population. This calculator is available online in the form of a free web-based tool that can aid clinicians in better patients counseling and treatment decision-making. Patient summary: We developed the Mount Sinai Prebiopsy Risk Calculator (MSP-RC) to assess the likelihood of any prostate cancer and clinically significant disease based on a combination of clinical and imaging characteristics. MSP-RC is applicable to all patient settings and accessible online.

MicroRNAs as Potential Liquid Biopsy Biomarker for Patients with Castration-Resistant Prostate Cancer.

Purpose: To identify micro-RNAs (miRNAs) expression profiles in peripheral blood plasma that could play a role as potential biomarkers in patients who progressed to castration-resistant prostate cancer (CRPC). Liquid biopsy analysis of miRNAs is a fast-developing field with a considerable likelihood to predict tumor progression and metastasis by targeting genes involved in oncogenesis. Patients and Methods: Differential expression analysis of miRNAs profile in CRPC patients was performed by creating small RNA libraries of circulating miRNAs using HiSeq2500 Illumina platform. A secondary analysis of aligned reads with miRNA identification and quantification was performed using miARmaSeq. Using the Bowtie algorithm, the selected variants were compared to reference nucleotide sequence GRCh38 and miRbase. Novel miRNA sequences were structurally analyzed using mirDeep2®. Results: A total of 16 patients with CRPC were included for analysis. Identified circulating miRNAs were hsa-miR-885-3p, hsa-miR-4467, hsa-miR-4686, hsa-miR-146a-3p, hsa-miR-6514-5p. Genes identified as regulated by these miRNAs were GPR56, BDNF, CTNND1, C17orf62, and DTNA. Conclusion: We explored the miRNA expression profile in patients with CRPC, identifying five miRNAs implicated in the regulation of genes involved in prostate cancer (PCa) oncogenesis and progression. We also found miRNA 855-3p in peripheral blood for the first time, which has a critical role in tumor growth mechanisms and higher expression profile than in healthy individuals.

Nomogram Predicting Adverse Pathology Outcome on Radical Prostatectomy in Low-Risk Prostate Cancer Men.

OBJECTIVE: To develop and validate a prediction model to predict the risk of adverse pathology outcome on final pathology in low-risk prostate cancer (PCa) men. MATERIALS AND METHODS: This study was a monocentric retrospective analysis of 426 men who underwent radical prostatectomy (RP) for low-risk PCa. The validation cohort included 103 men from another hospital. Adverse pathology outcome was defined either by upgrading on RP Gleason Score (GS) (from GS 3+3 to GS ≥ 3+4 with Gleason pattern 4 ≥ 10%) or a non-organ confined disease (pathologic stage ≥ pT3a). Multivariable logistic regression analysis was performed to build nomogram for predicting adverse pathology outcome. Nomogram validation was performed by calculating the area under receiver operating characteristic curves (AUC) and comparing nomogram-predicted probabilities with actual rates of adverse pathology outcome in the external cohort. The Kaplan-Meier method was used to estimate and compare the biochemical recurrence-free survival rates between the two groups. RESULTS: Of 426 men in the development cohort, 45.7% showed adverse pathology outcome on RP. Age, body mass index, prostate specific antigen density, history of prior negative biopsy, magnetic resonance imaging prostate imaging reporting and data system score 4-5 and percentage of positive biopsies were significant predictors in multivariate analysis. A nomogram was constructed with an area under curve of 87%. There was agreement between predicted and actual rates of adverse pathology outcome in the validation cohort. The 5-year biochemical recurrence-free survival rates in patients with and without adverse pathology outcome was 70% and 98%, respectively. CONCLUSION: This novel nomogram would help identify low-risk PCa men at risk of adverse pathology outcome and can be relevant for treatment decision-making.

Current strategies to improve erectile function in patients undergoing radical prostatectomy - preoperative scenario.

Radical prostatectomy (RP) is a common procedure for localized and locally advanced prostate cancer (PCa). Despite advances in the technique with the introduction of robotic surgery, erectile dysfunction (ED) remains a major drawback. Therefore, a personalized evaluation that considers the patient's expectations and cultural background, baseline erectile function (EF), health status, and tumoral extension is important to optimize outcomes. Since EF has a tremendous impact on the quality of life of the patient and the intimate partner, it is timely to review multidisciplinary approaches to be implemented in the preoperative setting. Here we propose various strategies divided into two main categories, namely, comprehensive preoperative planning and prehabilitation (Figure 1.).

Current strategies to improve erectile function in patients undergoing radical prostatectomy - postoperative scenario.

In order to optimize functional outcomes following radical prostatectomy (RP), early rehabilitation programs should be stablished in the clinical practice. A multidisciplinary approach to assess the patient's mental, physical and social well-being are as important as the implementation of pharmacological and mechanical interventions. In current article of the seminar, we focus on strategies to improve erectile function (EF) after surgery. These strategies have been grouped into 4 main categories: pharmacologic and mechanical interventions, psychosocial interventions, hormonal assessment and a final section dedicated to strategies under research.

Current strategies to improve erectile function in patients undergoing radical prostatectomy-intraoperative scenario.

Results after radical prostatectomy (RP) are generally judged by complete removal of the cancer, return of urinary control, and the ability to have intercourse. Given the complexity of the anatomy of the prostate and its relationship to the surrounding nerves, muscles, and fascia, RP is considered a challenging and technically demanding surgery. Here we propose multiple intraoperative strategies to optimize oncological and functional outcomes.

Technical advances in nerve-sparing and continence preservation.

PURPOSE OF REVIEW: Urinary incontinence and erectile dysfunction are common after radical prostatectomy. These side effects greatly impact patients' quality of life. Therefore, surgical techniques and technology tools are constantly being developed to optimize trifecta outcomes. Here we focus on advances in nerve-sparing (NS) and continence preservation. RECENT FINDINGS: New surgical techniques dedicated to preservation rather than reconstruction have been developed to improve urinary continence (UC) and NS. On the other hand, intraoperative assessment of prostatic and periprostatic structures has shown promising outcomes toward NS whereas avoiding omission of extracapsular extension (ECE). Likewise, neural regeneration strategies are under research to improve return of erectile function and UC. SUMMARY: Superb outcomes after Robot-Assisted Radical Prostatectomy require a proper balance between NS and risk of ECE. Detailed anatomic knowledge together with an accurate surgical planning are cornerstone for tailoring the approach in each case.

The Small Metal-Binding Protein SmbP Simplifies the Recombinant Expression and Purification of the Antimicrobial Peptide LL-37.

(1) Background: The cathelicidin peptide LL-37 is a prominent molecule with many biological activities, including antimicrobial. Due to its importance, here, we describe the production of LL-37 tagged with SmbP, a relatively new carrier protein that improves the production of recombinant proteins and peptides in Escherichia coli. We present an alternative method for the rapid expression, purification, and antimicrobial evaluation of LL-37, that involves only one purification step. (2) Methods: A DNA construct of SmbP_LL-37 was transformed into E. coli BL21(DE3); after overnight expression, the protein was purified directly from the cell lysate using immobilized metal-affinity chromatography. SmbP_LL-37 was treated with Enterokinase to obtain the free LL-37 peptide. The antimicrobial activity of both SmbP_LL-37 and free LL-37 was determined using the colony forming unit assay method. (3) Results: SmbP_LL-37 was observed in the soluble fraction of the cell lysate; after purification with IMAC, protein gel electrophoresis, and analysis by ImageJ, it showed 90% purity. A total of 3.6 mg of SmbP_LL-37 was produced from one liter of cell culture. SmbP_LL-37 and free LL-37 both showed inhibition activity against Staphylococcus aureus and Escherichia coli. (4) Conclusions: The SmbP fusion protein is a valuable tool for producing biologically-active LL-37 peptide. The production method described here should be of interest for the expression and purification of additional cationic peptides, since it cuts the purification time considerably prior to determination of antimicrobial activity.

Clinical Utility of Negative Multiparametric Magnetic Resonance Imaging in the Diagnosis of Prostate Cancer and Clinically Significant Prostate Cancer.

BACKGROUND: Multiparametric magnetic resonance imaging (MRI) is increasingly used to diagnose prostate cancer (PCa). It is not yet established whether all men with negative MRI (Prostate Imaging-Reporting and Data System version 2 score <3) should undergo prostate biopsy or not. OBJECTIVE: To develop and validate a prediction model that uses clinical parameters to reduce unnecessary prostate biopsies by predicting PCa and clinically significant PCa (csPCa) for men with negative MRI findings who are at risk of harboring PCa. DESIGN SETTING AND PARTICIPANTS: This was a retrospective analysis of 200 men with negative MRI at risk of PCa who underwent prostate biopsy (2014-2020) with prostate-specific antigen (PSA) >4 ng/ml, 4Kscore of >7%, PSA density ≥0.15 ng/ml/cm3, and/or suspicious digital rectal examination. The validation cohort included 182 men from another centre (University of Miami) with negative MRI who underwent systematic prostate biopsy with the same criteria. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: csPCa was defined as Gleason grade group ≥2 on biopsy. Multivariable logistic regression analysis was performed using coefficients of logit function for predicting PCa and csPCa. Nomogram validation was performed by calculating the area under receiver operating characteristic curves (AUC) and comparing nomogram-predicted probabilities with actual rates of PCa and csPCa. RESULTS AND LIMITATIONS: Of 200 men in the development cohort, 18% showed PCa and 8% showed csPCa on biopsy. Of 182 men in the validation cohort, 21% showed PCa and 6% showed csPCa on biopsy. PSA density, 4Kscore, and family history of PCa were significant predictors for PCa and csPCa. The AUC was 0.80 and 0.87 for prediction of PCa and csPCa, respectively. There was agreement between predicted and actual rates of PCa in the validation cohort. Using the prediction model at threshold of 40, 47% of benign biopsies and 15% of indolent PCa cases diagnosed could be avoided, while missing 10% of csPCa cases. The small sample size and number of events are limitations of the study. CONCLUSIONS: Our prediction model can reduce the number of prostate biopsies among men with negative MRI without compromising the detection of csPCa. PATIENT SUMMARY: We developed a tool for selection of men with negative MRI (magnetic resonance imaging) findings for prostate cancer who should undergo prostate biopsy. This risk prediction tool safely reduces the number of men who need to undergo the procedure.