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

Hood Technique for Radical Prostatectomy

The hood technique is a modification of the robotic-assisted radical prostatectomy used for the treatment of prostate cancer. The hood technique was developed in 2018 with the goal of preserving the structures anterior to the urethra during apical dissection to facilitate early postoperative recovery of urinary continence. Similar techniques have been published in the past, reporting excellent continence recovery rates, including the PERUSIA extraperitoneal technique and the retrograde release of the neurovascular bundle. Additionally, puboprostatic ligament sparing was shown to reduce postoperative urinary incontinence in the open era. The hood technique is an alternative to Retzius-sparing radical prostatectomy, which also spares the anterior structures by preserving the entire anterior space of Retzius.

Detection of Apical Cancer with Novel Imaging Modalities to Predict Apical Margin Positivity in Robotic Assisted Radical Prostatectomy

OBJECTIVES

To evaluate margin positivity at apex utilizing preoperative magnetic resonance imaging [MRI], micro-ultrasound [MUS], prostate specific membrane antigen positron emission tomography PSMA PET] scan, biopsy location and intraoperative timing of deep venous complex [DVC] ligation during robot assisted radical prostatectomy [RARP].

METHODS

Institution review board approved retrospective study underwent RARP between November 2022 to March 2024. All patients underwent preoperative MRI, MUS and PSMA PET scan. Patients underwent RARP using either standard DVC [done prior apical dissection] ligation or delayed DVC [after prostate removal] technique. All patients underwent intra operative frozen section analysis by an experienced genitourinary pathologist. Descriptive statistics were performed. Data analyzed using R software version 4.3.3.

RESULTS

Total 619 prostate cancer patients underwent RARP. Of these, 365 men underwent RARP using delayed DVC ligation technique and 254 men using standard DVC ligation technique. There was no statically significant difference in 2 groups on demographic parameters, MRI, MUS and PSMA-PET scan features. Sensitivity of MRI, MUS, PSMA-PET and prostate biopsy for detection of apical positive margin were 66%, 81%, 81% and 73% respectively. Specificity of MRI, MUS, PSMA-PET and prostate biopsy for detection of apical positive margin were 45%, 14%, 16% and 30% respectively. When all modalities are used accumulatively, apical cancer was missed only in 1% of cases.

CONCLUSIONS

With proper preoperative understanding of apical lesion location, timing of DVC ligation [standard vs delayed] doesn't impact apical positive surgical margins. Combination of MRI, MUS, PSMA-PET and prostate biopsy reduce apical positive surgical margin rates significantly.

Development of a microultrasound-based nomogram to predict extra-prostatic extension in patients with prostate cancer undergoing robot-assisted radical prostatectomy

OBJECTIVES

To develop a microultrasound-based nomogram including clinicopathological parameters and microultrasound findings to predict the presence of extra-prostatic extension and guide the grade of nerve-sparing.

MATERIAL AND METHODS

All patients underwent microultrasound the day before robot-assisted radical prostatectomy. Variables significantly associated with extra-prostatic extension at univariable analysis were used to build the multivariable logistic model, and the regression coefficients were used to develop the nomogram. The model was subjected to 1000 bootstrap resamples for internal validation. The performance of the microultrasound-based model was evaluated using the area under the curve (AUC) of the receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis (DCA).

RESULTS

Overall, 122/295 (41.4%) patients had a diagnosis of extra-prostatic extension on definitive pathology. Microultrasound correctly identify extra-prostatic extension in 84/122 (68.9%) cases showing a sensitivity and a specificity of 68.9% and 84.4%, with an AUC of 76.6%. After 1000 bootstrap resamples, the predictive accuracy of the microultrasound-based model was 85.9%. The calibration plot showed a satisfactory concordance between predicted probabilities and observed frequencies of extra-prostatic extension. The DCA showed a higher clinical net-benefit compared to the model including only clinical parameters. Considering a 4% cut-off, nerve-sparing was recommended in 173 (58.6%) patients and extra-prostatic extension was detected in 32 (18.5%) of them.

CONCLUSION

We developed a microultrasound-based nomogram for the prediction of extra-prostatic extension that could aid in the decision whether to preserve or not neurovascular bundles. External validation and a direct comparison with mpMRI-based nomogram is crucial to corroborate our results.

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.

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.

Microultrasound in the detection of the index lesion in prostate cancer

INTRODUCTION AND OBJECTIVE

The natural progression of prostate cancer is primarily driven by an index lesion (IL). Studies have shown that different metastases within the same patient arise from a single precursor cell. Therefore, our aim is to assess the effectiveness of transrectal microultrasound (MUS) in comparison to multiparametric magnetic resonance imaging (mpMRI) for detecting the IL in prostate cancer. We used quarter-mount pathological results as the reference standard for this evaluation.

MATERIALS AND METHODS

Three hundred and sixty-three patients who underwent Robot-Assisted Radical Prostatectomy (RARP) from June 2021 to August 2022 were included. All received mpMRI and MUS before RARP. MUS was performed by experienced operators blinded to mpMRI and biopsy results. The IL in the radical prostatectomy specimen was defined as the lesion with extraprostatic extension, the highest Grade Group (GG), or the largest tumor volume if the GG was the same. The correlation between imaging and final pathology findings was performed. A descriptive statistical analysis is presented.

RESULTS

The patients' prostates were analyzed in 12 regions (anterior/posterior, right/left, apex/mid/base). A total of 4308 regions were identified. Of these, 935 were involved by the ILs. Compared with final pathology, MUS demonstrated a sensitivity, specificity, PPV, and NPV of 68.7%, 96.3%, 80.8%, and 93.1%, respectively, while mpMRI showed a sensitivity, specificity, PPV, and NPV of 68.6%, 97.2%, 86.1%, and 92.5%, respectively, for the detection of the IL. Most of the lesions missed by MUS were located in the anterior zone (62%).

CONCLUSION

MUS exhibits a diagnostic performance similar to mpMRI when it comes to detecting the IL in prostate cancer. MUS is a cost-effective option, offers real-time evaluation, and has no delay in the acquisition process.

Development and Validation of Nomograms Based on Nutritional Risk Index for Predicting Extracapsular Extension and Seminal Vesicle Invasion in Patients Undergoing Radical Prostatectomy

BACKGROUND

The aim of the study was to investigate the predictive value of the nutritional risk index (NRI) for extracapsular extension (ECE) and seminal vesicle invasion (SVI) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP), and further develop and validate predictive nomograms for ECE and SVI based on the NRI.

METHODS

We retrospectively analyzed 734 PCa patients who underwent RP between 2010 and 2020 in the Department of Urology at Peking University Third Hospital. The enrolled patients were randomly divided into a primary cohort (n = 489) and a validation cohort (n = 245) in a 2:1 manner. The baseline NRI of patients was calculated using serum albumin level and body mass index, and a malnutrition status was defined as NRI ≤ 98. Univariate and multivariate logistic regression analyses were conducted to identify predictors for ECE and SVI. Nomograms for predicting ECE and SVI were established based on the results of the multivariate logistic regression analysis. The performance of the nomograms was estimated using Harrell's concordance index (C-index), the area under curve (AUC) of receiver operating characteristic (ROC) curves and the calibration curves.

RESULTS

In the primary cohort, 70 (14.3%) patients with NRI ≤ 98 were classified as malnutrition, while the remaining 419 (85.7%) patients with NRI > 98 were considered to have normal nutrition. The nomograms for predicting ECE and SVI shared common factors including NRI, percentage of positive biopsy cores (PPC) and biopsy Gleason score, while prostate-specific antigen (PSA) levels and PSA density (PSAD) were only incorporated in ECE nomogram. The C-indexes of the nomograms for predicting ECE and SVI were 0.785 (95% confidence interval (CI): 0.745 - 0.826) and 0.852 (95% CI: 0.806 - 0.898), respectively. The calibration curves demonstrated excellent agreement between the predictions by the nomograms and the actual observations. The results remained reproducible when the nomograms were applied to the validation cohort.

CONCLUSIONS

The NRI is significantly associated with ECE and SVI in PCa patients. The nomogram established based on the NRI in our study can provide individualized risk estimation for ECE and SVI in PCa patients, and may be valuable for clinicians in making well-informed decisions regarding treatment strategies and patient management.

Robot-Assisted Radical Prostatectomy by Lateral Approach: Technique, Reproducibility and Outcomes

BACKGROUND

Radical prostatectomy by lateral approach allows performing a prostatectomy through a buttonhole, with direct access to the seminal vesicle and fully sparing the anterior pubovesical complex. Our aim is to show the results of reproducing the technique of robotic radical prostatectomy by lateral approach, in terms of intraoperative, postoperative, oncological and functional parameters.

METHODS

We analyzed 513 patients submitted to robotic radical prostatectomy by lateral approach from January 2015 to March 2021, operated on by two surgeons in our institution. The oncological and functional results of both surgeons were compared.

RESULTS

When comparing both surgeons, the rate of positive surgical margins (PSM) was 32.87% and 37.9% and significant surgical margins (PSM > 2 mm) were 5.88% and 7.58% (p = 0.672) for surgeon 1 and surgeon 2, respectively. Immediate continence was 86% and 85% and sexual potency at one year 73% and 72%, with a similar rate of complications for surgeon 1 and 2.

CONCLUSIONS

Radical prostatectomy by the lateral approach technique with preservation of the anterior pubovesical complex is reproducible and offers good oncological and functional results.

The diagnostic accuracy of micro-ultrasound for prostate cancer diagnosis: a review

PURPOSE

Micro-UltraSound (microUS) is a new imaging modality capable of identifying and targeting suspicious areas, which might further increase the diagnostic yield of prostate biopsy (PBx). Aim of this review is to provide insights into the usefulness of microUS for the sub-stratification of prostate cancer (PCa), clinically significant PCa (i.e., any Gleason score ≥ 7 PCa; csPCa) along with non-organ-confined disease in patients undergoing PBx.

METHODS

A PubMed literature search was performed using keywords: prostate cancer diagnosis, prostate cancer diagnosis surveillance, systematic biopsy, target biopsy, micro-ultrasound, and prostate risk identification using micro-ultrasound.

RESULTS

MicroUS could significantly improve multiparametric magnetic resonance imaging (mpMRI) findings by adding valuable anatomical and pathological information provided by real-time examination. Furthermore, microUS target biopsy could replace systematic biopsy in clinical practice by reducing the detection of clinically insignificant (ciPCa) and increasing that of csPCa. Finally, microUS may be useful in predicting the presence of non-organ confined PCa before radical prostatectomy and it could also be an effective add-on tool for patient monitoring within the active surveillance program.

CONCLUSION

MicroUS may represent an attractive step forward for the management of csPCa as a complementary or alternative tool to mpMRI. Nevertheless, further longitudinal studies are warranted, and the strength of the evidence is still suboptimal to provide clear recommendations for daily clinical practice.