Investigating the mechanism underlying urinary continence using dynamic MRI after Retzius-sparing robot-assisted radical prostatectomy

A novel anterior approach toward robotic radical prostatectomy is associated with earlier continence recovery than the conventional approach

OBJECTIVES

To advance robotic radical prostatectomy, we developed a novel anterior approach that uses a peritoneal incision created between the umbilical ligaments to develop the Retzius space and thus spares vessels that surround the bladder and prostate, with the space being closed after prostatectomy and vesicourethral anastomosis. This approach may improve continence recovery. We investigated continence recovery following the novel anterior approach compared to after the conventional anterior approach.

METHODS

We retrospectively reviewed 516 patients who underwent robotic radical prostatectomy from January 2019 to July 2023. We compared continence recovery following our novel anterior approach (N = 282) to that after conventional anterior approach (N = 234), and we compared the oncological outcomes and safety profiles of the two groups.

RESULTS

Patient demographics did not differ significantly between the two groups. Continence recovery in patients undergoing the novel anterior approach was significantly better than that of patients treated via the conventional approach (hazard ratio: 1.651, 95% confidence interval: 1.325-2.057, p < 0.0001). Use of the novel anterior approach in addition to nerve sparing and preservation of the detrusor apron independently predicted continence, and the mixture of these three techniques afforded excellent continence recovery (1- and 2-year total continence rate of 81.1% and 93.7%). Neither the biochemical recurrence-free survival nor the complication rate differed significantly between the two groups.

CONCLUSION

Our novel anterior approach may improve continence recovery compared to the conventional anterior approach, without compromising the oncological outcomes. Prospective comparative studies are necessary to confirm the benefits of this approach.

Retzius sparing robot-assisted radical prostatectomy: optimizing functional results

PURPOSE

The aim of this study is to critically evaluate the existing body of evidence regarding the efficacy of Retzius-sparing radical prostatectomy (RS-RARP) in achieving improved functional outcomes. Moreover, we explored possible strategies to further optimize functional outcomes.

METHODS

Following PRISMA guidelines, a systematic review (PROSPERO ID CRD42024539915) was performed on 9th September 2023 on PubMed, Scopus, and Web of Science. Only original articles in the English language reporting functional outcomes after RS-RARP were included.

RESULTS

Overall, the search string yielded 99 results on PubMed, 122 on Scopus, and 120 on Web Of Science. After duplicate exclusion, initial screening and eligibility evaluation, a total of 47 studies were included in the qualitative analysis, corresponding to a cohort of 13.196 patients. All studies reported continence recovery. RS-RARP appeared to achieve better and faster continence recovery compared to S-RARP. However, it should be noted that continence definition was heterogeneous and not based on validated condition-specific questionnaires. Seven (15%) studies provided for any sort of rehabilitation for urinary incontinence after RS-RARP. 22 studies analyzed potency recovery rates, showing no difference between RS-RARP and S-RARP. The evaluation of this outcome poses a great challenge due to the lack of standardized assessment tools and reporting methods. Only two studies reported on the consistent use of post-operative PDE5i as penile rehabilitation.

CONCLUSIONS

The current review highlights the satisfactory functional results of Retzius-sparing robot assisted radical prostatectomy, which holds true irrespective of disease stage and prostate volume, with promising results even in patients previously treated for BPH or in the salvage setting. How can we optimize those results? The answer does not probably lie in further refinement of the surgical technique, but in giving greater attention to patient counselling and rehabilitation strategies in order to minimize regret and maximize satisfaction.

Comparative analysis of perioperative outcomes in obese patients undergoing robot-assisted radical prostatectomy (RARP) versus open radical prostatectomy (ORP): a systematic review and meta-analysis

The purpose of this study was to conduct a comparative analysis of the perioperative outcomes associated with robot-assisted laparoscopic prostatectomy (RARP) versus open radical prostatectomy (ORP) in the obese population diagnosed with prostate cancer. We performed a comprehensive search in key databases such as PubMed, Embase, Web of Science, and the Cochrane Library, encompassing studies of all languages, with a final search date of April 2024. We also omitted articles that consisted of conference abstracts and content that was not pertinent to our study. The aggregated outcomes were evaluated utilizing the metrics of weighted mean differences (WMDs) and odds ratios (ORs). A sensitivity analysis was also integrated into our assessment. The meta-analysis was facilitated by employing Stata/MP version 18 software. Additionally, the study was duly registered with PROSPERO under the identifier: CRD 42024540216. This meta-analysis, which included five trials, shows that compared to ORP, RARP is associated with a reduced estimated blood loss (EBL) (WMD -445.77, 95%CI -866.08, -25.45; p = 0.038), a decreased transfusion rate (OR 0.17, 95%CI 0.13, 0.21; p < 0.001), and a diminished overall complication rate (OR 0.71, 95%CI 0.58, 0.86; p = 0.001). No statistically significant differences were found in operative time (OT) (WMD 1.88, 95%CI -46.53, 50.28; p = 0.939) or length of stay (LOS) (WMD -0.41, 95%CI -1.07, 0.25; p = 0.221). Among patients with obesity and prostate cancer, RARP demonstrates advantages over ORP by reducing estimated blood loss, transfusion requirements, and the incidence of complications. Notably, there were no significant differences in operative duration and hospital stay between the two surgical approaches. These findings suggest that RARP could be a preferable surgical option for obese individuals with prostate cancer.

Comparison of postoperative urinary continence and incontinence types between conventional and Retzius-sparing robot-assisted radical prostatectomy

AIMS

This study aimed to investigate the postoperative urinary continence rate and incontinence types compared over time between conventional robot-assisted radical prostatectomy (C-RARP) and Retzius-sparing RARP (RS-RARP).

METHODS

All 61 cases were selected from the C-RARP and RS-RARP by propensity score matching, and the pad scale, 24-h pad weight test, and International consultation on incontinence questionnaire-short form (ICIQ-SF) were followed-up over time up to 12 months.

RESULTS

The probability of urinary continence per pad scale evaluation differed according to how it was defined: the continence rate 12 months after C-RARP and RS-RARP were 94% and 95% for 1 pad/day, 85% and 92% for 1 security pad/day, 61% and 85% for no pad use, respectively, which were all significantly better with RS-RARP. The results of the 24-h pad weight test were significantly better with RS-RARP at both 3 and 12 months, with median C-RARP versus RS-RARP values of 5 versus 1 g and 2 versus 0 g, respectively. In terms of types of urinary incontinence, the rates of postoperative stress urinary incontinence (SUI) increased in both procedures but to a lesser extent in RS-RARP. Other types of urinary incontinence, such as urge incontinence and terminal dribbling, did not differ significantly before and after surgery and between the two procedures.

CONCLUSIONS

Postoperative urinary continence was better with RS-RARP than with C-RARP per all follow-up parameters until 12 months postoperatively. Postoperative SUI was significantly lower with RS-RARP than with C-RARP, which was considered the main reason for better postoperative urinary continence with RS-RARP.

Postoperative functional and cancer control evaluation of conventional and Retzius-sparing robot-assisted radical prostatectomy: Comparison of selected cases by propensity score matching

AIM

Although many reports have shown that Retzius-sparing robot-assisted radical prostatectomy (RS-RARP) is effective for postoperative urinary continence, the postoperative voiding status and sexual function associated with this technique have not yet been adequately compared with those associated with conventional RARP (C-RARP). In this study, the lower urinary tract function, erectile function, and cancer control after C-RARP and RS-RARP were compared chronologically.

MATERIALS AND METHODS

We selected 50 cases of C-RARP and RS-RARP each by propensity score matching and evaluated them over time using various questionnaires. Urinary continence recovery rates and biochemical recurrence (BCR)-free survival rates were calculated using the Kaplan-Meier method and compared between the two groups using the log-rank test.

RESULTS

When urinary continence was defined as 0 pads per day, 0 pads per day + 1 security linear, or ≤1 pad per day, the postoperative improvement in urinary continence was better with RS-RARP over the course of up to 1 year for all definitions. The International Consultation on Incontinence Questionnaire-Short Form total scores and the Overactive Bladder Symptom Scores were better in the postoperative RS-RARP group. There were no significant differences in the International Prostate Symptom Score total score, QOL score, and erectile hardness score between the two groups during the observation period. The BCR-free survival did not differ significantly between the two groups CONCLUSIONS: Postoperative urinary continence was better in the RS-RARP group than in the C-RARP group; however, the voiding function, erectile function, and cancer control did not differ significantly.

Contribution of Retzius-sparing robot-assisted radical prostatectomy to the mechanism of urinary continence as demonstrated by dynamic MRI

Retzius-sparing robot-assisted radical prostatectomy (RARP) has been reported to exhibit better postoperative urinary continence, but the reasons behind this are unknown. This study included 254 cases who underwent RARP and underwent postoperative dynamic MRI. We measured the urine loss ratio (ULR) immediately after postoperative urethral catheter removal and investigated its affecting factors and the mechanisms. Nerve-sparing (NS) techniques was performed in 175 (69%) unilateral and 34 (13%) bilateral cases, whereas Retzius-sparing in 58 (23%) cases. The median ULR early after indwelling catheter removal in all patients was 4.0%. The multivariate analysis was performed on factors that reduce ULR and found that the following factors were associated with ULR: younger age, NS and Retzius-sparing, which were significant. Additionally, dynamic MRI findings showed that membranous urethral length and the anterior rectal wall movement toward the pubic bone during abdominal pressure were significant factors. The movement observed on the dynamic MRI during abdominal pressure was thought to reflect an effective urethral sphincter closure mechanism. Long membranous urethral length and an effective urethral sphincter closure mechanism during abdominal pressure were considered effective for favorable urinary continence after RARP. NS and Retzius-sparing were clearly shown to have an additive effect in preventing urinary incontinence.

Modified anterior approach preserving Retzius space versus standard anterior approach robot-assisted radical prostatectomy: A matched-pair analysis

Objective

To compare our initial perioperative and postoperative outcomes of the modified anterior approach (MA) with Retzius space preservation robot-assisted radical prostatectomy (RARP) with the standard anterior approach (SA) RARP.

Materials and methods

A retrospective analysis was performed on 116 patients with RARP completed by the same surgeon between September 2019 and March 2022. They were divided into SA-RARP group (77 cases) and MA-RARP group (39 cases). Propensity score matching was performed using eight preoperative variables, including age, BMI, preoperative PSA, biopsy Gleason score, prostate volume, D'Amico risk classification, SHIM, and clinical T stage. Functional outcome was assessed by urine pad count and SHIM after surgery, and oncological outcome was assessed by statistics of postoperative pathological findings as well as follow-up postoperative PSA. The median follow-up was 13 months and 17 months for MA-RARP and SA-RARP groups respectively.

Results

Propensity score matching was performed 1:1, and baseline data were comparable between the two groups after matching. Comparison of postoperative data: MA-RARP group had less mean EBL than SA-RARP group (200 vs 150 ml, p = 0.033). PSM did not differ between groups (p = 1). In terms of urinary control recovery, the MA-RARP group showed significant advantages in urinary control recovery at 24 h, 2 weeks, 1 month and 3 months after catheter removal, respectively (48.6% vs 5.7%, p < 0.001; 80% vs 22.9%, p < 0.001; 94.3% vs 51.4%, p < 0.001; 100% vs 74.3%, p = 0.002). This advantage gradually disappeared 6 months or more after surgery. The median time to recovery of sexual function was shorter in the MA-RARP group (165 vs 255 d, p = 0.001).

Conclusion

MA-RARP is safe and reliable, and can achieve better early urinary control function and sexual function recovery while achieving the primary tumor control goal.

Impact of Pelvic Anatomical Changes Caused by Radical Prostatectomy

Simple Summary

After radical prostatectomy, the pelvic anatomy is altered such that the postoperative structure differs from the preoperative one, resulting in a variety of complications. In this review, the complications and mechanisms of pelvic anatomical changes associated with radical prostatectomy, as well as countermeasures, are outlined. An analysis of the anatomical mechanisms that cause complications after radical prostatectomy using imaging and other modalities is in progress. In addition, many surgical techniques that ensure the prevention of postoperative complications have been reported, and their usefulness has been evaluated. The preservation of as much periprostatic tissue and periprostatic structures as possible may lead to favorable postoperative functions, as long as the cancer condition permits.

Abstract

During radical prostatectomy, the prostate is removed along with the seminal vesicles, and the urinary tract is reconstructed by dropping the bladder onto the pelvic floor and suturing the bladder and urethra together. This process causes damage to the pelvic floor and postoperative complications due to the anatomical changes in the pelvic floor caused by the vesicourethral anastomosis. Urinary incontinence and erectile dysfunction are major complications that impair patients’ quality of life after radical prostatectomy. In addition, the shortening of the penis and the increased prevalence of inguinal hernia have been reported. Since these postoperative complications subsequently affect patients’ quality of life, their reduction is a matter of great interest, and procedural innovations such as nerve-sparing techniques, Retzius space preservation, and inguinal hernia prophylaxis have been developed. It is clear that nerve sparing is useful for preserving the erectile function, and nerve sparing, urethral length preservation, and Retzius sparing are useful for urinary continence. The evaluation of pre- and postoperative imaging to observe changes in pelvic anatomy is also beginning to clarify why these techniques are useful. Changes in pelvic anatomy after radical prostatectomy are inevitable and, therefore, postoperative complications cannot be completely eliminated; however, preserving as much of the tissue and structure around the prostate as possible, to the extent that prostate cancer control is not compromised, may help reduce the prevalence of postoperative complications.