Intrafascial versus interfascial nerve sparing in radical prostatectomy for localized prostate cancer: a systematic review and meta-analysis

Erectile function, urinary continence and oncologic outcomes of neurovascular bundle sparing robot-assisted radical prostatectomy for high-risk prostate cancer: A systematic review and meta-analysis

Background

The nerve-sparing (NS) effect of robot-assisted radical prostatectomy (RARP) on patients with a high-risk prostate cancer remains unclear. The objective of this study was to compare the urinary continence, erectile function and oncology outcomes of the nerve-sparing and non-nerve-sparing (NNS) group during RARP surgeries.

Methods

We systematically searched databases including PubMed, Embase, Cochrane Library and Web of Science to identify relevant studies published in English up to December 2022. Newcastle-Ottawa Scale (NOS) was used as a quality evaluation tool to evaluate the quality of the literature parameters involved, including urinary continence, erectile function and oncologic outcomes, which were compared using the Stata 15.1 software (StataSE, USA).

Results

A total of 8 cohort studies involving 2499 patients were included. A meta-analysis of results showed that the NS group was beneficial to the recovery of urinary continence (RR 0.46, 95%CI 0.22, 0.96; p=0.045<0.05) and erectile function (RR 0.32, 95%CI 0.16, 0.63; p=0.001<0.05) 12 months after surgeries, which showed a better oncological outcome (RR 1.31, 95%CI 1.01, 1.69; p=0.01<0.05).

Conclusions

The current study results indicate that intraoperative NS during RARP is beneficial to long-term postoperative functional recovery and tumor prognosis of patients with high-risk prostate cancers. Due to interstudy interferences, the results should be interpreted with caution.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022384647.

Different Nerve-Sparing Techniques during Radical Prostatectomy and Their Impact on Functional Outcomes

Simple Summary

Optimum preservation of potency and continence after radical prostatectomy (RP) are equally important surgical endpoints as cancer control itself. Nerve-sparing technique during RP has a major impact to both oncological and functional outcomes of the procedure and various different techniques have been developed aiming to optimize its outcomes. This literature review aims to summarize all different nerve-sparing techniques applied during RP from its first description from Patrick C. Walsh to its newer trends. The review underlines that optimum nerve-sparing expands far beyond recognising and preserving the anatomical integrity of the neurovascular bundles. It also emphasises that nerve-sparing is a field under constant development, with new technologies entering continuously the nerve-sparing field corresponding to the evolving open, laparoscopic and robotic-assisted RP approaches.

Abstract

The purpose of this narrative review is to describe the different nerve-sparing techniques applied during radical prostatectomy and document their functional impact on postoperative outcomes. We performed a PubMed search of the literature using the keywords “nerve-sparing”, “techniques”, “prostatectomy” and “outcomes”. Other potentially eligible studies were retrieved using the reference list of the included studies. Nerve-sparing techniques can be distinguished based on the fascial planes of dissection (intrafascial, interfascial or extrafascial), the direction of dissection (retrograde or antegrade), the timing of the neurovascular bundle dissection off the prostate (early vs. late release), the use of cautery, the application of traction and the number of the neurovascular bundles which are preserved. Despite this rough categorisation, many techniques have been developed which cannot be integrated in one of the categories described above. Moreover, emerging technologies have entered the nerve-sparing field, making its future even more promising. Bilateral nerve-sparing of maximal extent, athermal dissection of the neurovascular bundles with avoidance of traction and utilization of the correct planes remain the basic principles for achieving optimum functional outcomes. Given that potency and continence outcomes after radical prostatectomy are multifactorial endpoints in addition to the difficulty in their postoperative assessment and the well-documented discrepancy existing in their definition, safe conclusions about the superiority of one technique over the other cannot be easily drawn. Further studies, comparing the different nerve-sparing techniques, are necessary.

Neurovascular bundle preservation in robotic-assisted radical prostatectomy: How I do it after 15.000 cases

Despite the neuroanatomy knowledge of the prostate described initially in the 1980's and the robotic surgery advantages in terms of operative view magnification, potency outcomes following robotic-assisted radical prostatectomy still challenge surgeons and patients due to its multifactorial etiology. Recent studies performed in our center have described that, in addition to the surgical technique, some important factors are associated with erectile dysfunction (ED) following robotic-assisted radical prostatectomy (RARP). These include preoperative Sexual Health Inventory for Men (SHIM) score, age, preoperative Gleason score, and Charlson Comorbidity Index (CCI). After performing 15,000 cases, in this article we described our current Robotic-assisted Radical Prostatectomy technique with details and considerations regarding the optimal approach to neurovascular bundle preservation.

Robot-Assisted Radical Prostatectomy Maneuvers to Attenuate Erectile Dysfunction: Technical Description and Video Compilation

Erectile dysfunction (ED) remains a significant problem in up to 63% of men after robot-assisted radical prostatectomy (RARP). After the discovery of the neurovascular bundle (NVB), additional anatomic description and variation in nerve-sparing (NS) techniques have been described to improve post-RARP ED. However, it remains questionable whether ED rates have improved over time, and this is concerning as competing treatments are introduced that have better ED outcomes. In this review, we describe RARP NS technical modifications that improve erectile function recovery. We focused on reports that included detailed anatomical descriptions as well as video illustrations to disseminate technique. We found that the alternative RARP NS surgical techniques provide better outcomes compared with standard NS RARP. The use of validated quality of life questionnaires is necessary for the appropriate comparison of outcomes. However, the retrospective character and inherent weaknesses of the included studies do not allow one to conclude which is the best NS approach. Overall, there is significant variation in RARP NS techniques and outcomes, and the ideal technical maneuvers to optimize outcomes remains subject to debate. However, there is a consensus on the importance of anatomically dissecting the NVB, minimizing traction and thermal injury as well as preserving the periprostatic fascia. Well-designed randomized controlled trials with videos describing details of different surgical techniques for generalizability are needed to consistently and objectively evaluate sexual function outcomes after RARP to optimize postoperative potency.

Clinical use of expanded prostate cancer index composite-based health-related quality of life outcomes after robot-assisted radical prostatectomy for localized prostate cancer

Background

This study aimed to assess the longitudinal health-related quality of life (HRQOL) using the Expanded Prostate Cancer Index Composite (EPIC) and HRQOL change between the nerve-sparing technique in Japanese men treated with robot-assisted radical prostatectomy (RARP).

Methods

A total of 573 patients who received RARP were included in this study. EPIC questionnaire was administered before treatment and up to 36 months after RARP. Clinical recovery was defined as half of the standard deviation of the baseline score for each domain. We divided all patients into recovery group or nonrecovery group. The time from survey to each domain recovery was calculated using the Kaplan–Meier method. We compared the sexual and urinary score change between groups using analysis of variance to confirm the effect of nerve-sparing technique.

Results

The median age was 67 years (interquartile range, 62–71 years). The mean score of all urinary domains worsened noticeably after 1 month. All postoperative urinary summary, function, and incontinence scores were significantly lower than preoperative scores up to 3 years post-RARP. Postoperative sexual summary and functional scores were significantly lower than preoperative score at all follow-up times throughout the 36 months. The recovery rate for the urinary incontinence domain was the lowest (44.5%), whereas the recovery rate for the urinary irritative–obstructive domain was the highest (73.7%). In the sexual domain, the bother domain had a higher recovery rate (73.0%) than the functional domain (29.7%). Although the recovery of sexual domains was slower compared with other domains, by 36 months after RARP, almost all values had recovered. Compared with other technique groups, bilateral intrafascial nerve-sparing group showed significantly decreased change in subscale scores before and after RARP in several sexual and urinary domain.

Conclusion

The time course and extent of functional and bother domain recovery documented in this study may prove useful for RARP patient selection in Japan.

Evaluation of Oncological Outcomes and Data Quality in Studies Assessing Nerve-sparing Versus Non-Nerve-sparing Radical Prostatectomy in Nonmetastatic Prostate Cancer: A Systematic Review

CONTEXT

Surgical techniques aimed at preserving the neurovascular bundles during radical prostatectomy (RP) have been proposed to improve functional outcomes. However, it remains unclear if nerve-sparing (NS) surgery adversely affects oncological metrics.

OBJECTIVE

To explore the oncological safety of NS versus non-NS (NNS) surgery and to identify factors affecting the oncological outcomes of NS surgery.

EVIDENCE ACQUISITION

Relevant databases were searched for English language articles published between January 1, 1990 and May 8, 2020. Comparative studies for patients with nonmetastatic prostate cancer (PCa) treated with primary RP were included. NS and NNS techniques were compared. The main outcomes were side-specific positive surgical margins (ssPSM) and biochemical recurrence (BCR). Risk of bias (RoB) and confounding assessments were performed.

EVIDENCE SYNTHESIS

Out of 1573 articles identified, 18 studies recruiting a total of 21 654 patients were included. The overall RoB and confounding were high across all domains. The most common selection criteria for NS RP identified were characteristic of low-risk disease, including low core-biopsy involvement. Seven studies evaluated the link with ssPSM and showed an increase in ssPSM after adjustment for side-specific confounders, with the relative risk for NS RP ranging from 1.50 to 1.53. Thirteen papers assessing BCR showed no difference in outcomes with at least 12 mo of follow-up. Lack of data prevented any subgroup analysis for potentially important variables. The definitions of NS were heterogeneous and poorly described in most studies.

CONCLUSIONS

Current data revealed an association between NS surgery and an increase in the risk of ssPSM. This did not translate into a negative impact on BCR, although follow-up was short and many men harbored low-risk PCa. There are significant knowledge gaps in terms of how various patient, disease, and surgical factors affect outcomes. Adequately powered and well-designed prospective trials and cohort studies accounting for these issues with long-term follow-up are recommended.

PATIENT SUMMARY

Neurovascular bundles (NVBs) are structures containing nerves and blood vessels. The NVBs close to the prostate are responsible for erections. We reviewed the literature to determine if a technique to preserve the NVBs during removal of the prostate causes worse cancer outcomes. We found that NVB preservation was poorly defined but, if applied, was associated with a higher risk of cancer at the margins of the tissue removed, even in patients with low-risk prostate cancer. The long-term importance of this finding for patients is unclear. More data are needed to provide recommendations.

A systematic review of nerve-sparing surgery for high-risk prostate cancer

INTRODUCTION

We provide a systematic analysis of nerve-sparing surgery (NSS) to assess and summarize the risks and benefits of NSS in high-risk prostate cancer (PCa).

EVIDENCE ACQUISITION

We have undertaken a systematic search of original articles using 3 databases: Medline/PubMed, Scopus, and Web of Science. Original articles in English containing outcomes of nerve-sparing radical prostatectomy (RP) for high-risk PCa were included. The primary outcomes were oncological results: the rate of positive surgical margins and biochemical relapse. The secondary outcomes were functional results: erectile function (EF) and urinary continence.

EVIDENCE SYNTHESIS

The rate of positive surgical margins differed considerably, from zero to 47%. The majority of authors found no correlation between NSS and a positive surgical margin rate. The rate of biochemical relapse ranged from 9.3% to 61%. Most of the articles lacked data on odds ratio (OR) for positive margin and biochemical relapse. The presented results showed no effect of nerve sparing (NS) on positive margin (OR=0.81, 0.6-1.09) or biochemical relapse (hazard ratio [HR]=0.93, 0.52-1.64). A strong association between NSS and potency rate was observed. Without NSS, between 0% and 42% of patients were potent, with unilateral 79-80%, with bilateral - up to 90-100%. Urinary continence was not strongly associated with NSS and was relatively good in both patients with and without NSS.

CONCLUSIONS

NSS may provide benefits for patients with urinary continence and significantly improves EF in high-risk patients. Moreover, it is not associated with an increased risk of relapse in short- and middle-term follow-up. However, the advantages of using such a surgical technique are unclear.

Optimizing Surgical Techniques in Robot-Assisted Radical Prostatectomy

Robot-assisted radical prostatectomy (RARP) is the most common surgical treatment of localized prostate cancer. The ideal procedure would achieve maximum oncological efficacy while minimizing associated side effects, such as erectile dysfunction and urinary incontinence. Surgeon experience and surgical technique affect RARP outcomes. Here, the authors review RARP technical modifications aimed at optimizing cancer control and postoperative urinary and sexual function.

Antiplatelet/anticoagulant agents for preventing thrombosis events in patients with severe COVID-19: A protocol for systematic review and meta-analysis

BACKGROUND

On March 11, 2020, World Health Organization announced that severe acute respiratory syndrome coronavirus 2 caused COVID-19 was a global pandemic. COVID-19 is associated with venous thromboembolism including deep vein thrombosis and pulmonary embolism. To further identify the current role of antiplatelet/anticoagulant therapy in the prophylaxis and treatment of COVID-19 patients is important.

METHODS

We will conduct a systematic review based on searches of major databases (eg, Pubmed, Web of Science, EMBASE, CENTRAL, MEDLINE, SCI-EXPANDED, CPCI-S, CBM, CNKI, and Wanfang Database) and clinical trial registries from inception to present without limitations of language and publication status. All published randomized control trials, quasi-randomized trials, retrospective and observational studies related to prophylactic antiplatelet/anticoagulant for severe COVID-19 will be included. Primary outcome includes incident acute thrombosis events. Second outcome is the incidence and severity of adverse effects. Full-text screening, data extraction and quality assessment will be conducted by 2 reviewers independently. The reporting quality, risk of bias, sensitivity analysis and subgroup analysis will be performed to ensure the reliability of our findings by other 2 researchers. The statistical analysis will be performed by RevMan V.5.3 software and Stata V.12.0 software.

RESULTS

The result of this systematic review will provide valid advice and consultation for clinicians on the management of prophylactic antiplatelet/anticoagulant for severe COVID-19 patients.

CONCLUSION

This systematic review will provide evidence for prophylactic antiplatelet/anticoagulant of severe COVID-19 patients.

PROSPERO REGISTRATION

CRD42020186928.

Effect of Panax ginseng on preventing acute respiratory tract infection: A protocol for systematic review and meta-analysis

BACKGROUND

Acute respiratory tract infection (ARTI) should be deeply concerned all over the world. Panax ginseng (ginseng) as traditional Chinese medicine is widely used in the treatment and health care for respiratory diseases. However, only one similar systematic review based on common cold has been published in 2011. New studies have occurred and a new systematic evaluation which could describe ARTI is needed.

METHODS AND ANALYSIS

We will search for randomized control trials of ginseng on preventing acute respiratory tract infection in the following 8 databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, AMED (via OVID) and 4 Chinese databases (Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Chinese Science and Technology Periodical Database, and Wan fang Database). The time is limited from the construction of the library to April 2020. The selection of studies, data extraction and quality of assessment will be conducted independently by 2 reviewers. The morbidity of ARTI by assessing self-report, caregiver report or clinical confirmation will be considered as the primary outcome. ARTI-related death among children or adults, other adverse events, absenteeism, laboratory-confirmed infection will be regarded as secondary outcome. All reported side effects and adverse events will be included as safety outcomes. Standard meta-analysis will be performed using Rev Man software V5.3.

RESULTS

This study will provide a better understanding of the association between P ginseng and ARTI.

CONCLUSION

This systematic review may offer stronger evidences for the clinicians to prevent the patients from ARTI and update the former one based on basic diseases and the safety.

PROSPERO REGISTRATION NUMBER

CRD42020181317.

Acupuncture for diminished ovarian reserve: Protocol for a systematic review and meta-analysis

BACKGROUND

The choice of treatments for diminished ovarian reserve (DOR) still remains a challenging clinical problem in reproductive medicine. Acupuncture could be beneficial for patients with DOR. This study aims to systematically investigate the efficacy and safety of the acupuncture for women with DOR.

METHODS

We will search electronic databases including PubMed (1946 to present), EMBASE (1974 to present), Cochrane Central Register of Controlled Trials (CENTRAL, all years), Web of Science (1900 to present), Chinese Biomedical Literatures Database (CBM, 1978 to present), China National Knowledge Infrastructure (CNKI, 1979 to present), WANFANG Data (from 2000 to present) to identify potentially eligible studies. Only randomized controlled trials (RCTs) will be included. Experimental interventions include traditional or contemporary acupuncture. Control interventions include no treatment, sham acupuncture, placebo acupuncture, or another active therapy. The primary outcomes include ongoing pregnancy rate and serum anti-Müllerian hormone level. A meta-analysis will be used to estimate a pooled intervention effect if possible.

RESULTS

The results will be published in a peer-reviewed journal.

CONCLUSION

The findings will provide further evidence for the management of DOR.

PROSPERO REGISTRATION NUMBER

CRD42018114385.

Oncological safety of intrafascial nerve-sparing radical prostatectomy compared with conventional process: a pooled review and meta-regression analysis based on available studies

Background

Intrafascial prostatectomy was a modified technique from the conventional nerve-sparing surgery in order to improve patients’ post-surgical continence and erectile function; however, ongoing controversy exists regarding the oncological safety of this technique. In this study we aimed to provide a critical and pooled analysis based on published literatures regarding the oncological outcomes after intrafascial nerve-sparing prostatectomy.

Methods

Database searches were performed for published articles till June 2018 on PubMed. Three reviewers screened fulfilled papers and extracted data independently. Main outcome was the positive surgical margins (PSMs) rates stratified by pathological stages. We performed both one-arm and comparative meta-analysis to evaluate the oncological safety of intrafascial technique. Moreover, we built meta-regression models to assess the confounding factors.

Results

We retrieved a total of 117 records after electronic search, of which 21 studies were finally included in this review. There were 15 controlled studies and 6 surgical series. Our one-arm meta-analysis demonstrated that the total PSM rates after intrafascial techniques ranging from 2.2 to 35%, with a pooled rate of 14.5% on average (480 of 3151 patients, 95% confidence interval[CI]: 11.2–17.5%). Meta-regression model showed that patients’ age, pT2 cancer percentage and Selection Score of Oncological Safety (SSOS) were significantly associated with total PSM rate; moreover, each 1 point of SSOS could decrease the total PSM rate by 1.3% on average. Comparative meta-analysis demonstrated that there was no significant difference between intra- and inter-fascial group regarding PSM rates.

Conclusions

With stringent case selection and when performed by experienced surgeons, intrafascial prostatectomy could offer an acceptable or, at least, equivalent PSM rate compared with the conventional interfascial approach. Preoperative SSOS more than 7 points could be considered as an indication of intrafascial radical prostatectomy.

Electronic supplementary material

The online version of this article (10.1186/s12894-019-0476-2) contains supplementary material, which is available to authorized users.

A novel intraoperative physician-assigned grading score to predict postoperative return of potency at 1 year after robotic-assisted laparoscopic prostatectomy

Introduction:

We examined a novel method of grading nerve sparing in robotic-assisted laparoscopic radical prostatectomy to better predict the potency outcomes of patients at 1-year after surgery. This grading (scale) was based on the surgeon's criteria of intraoperative findings during completion of nerve sparing. This grading was then analyzed statistically to validate its association with potency outcomes.

Methods:

We devised a study module based on measurable visual cues intraoperatively where the surgeon risk stratified the surgery into four grades depending on the completeness of nerve sparing, keeping in mind the known parameters influencing potency outcomes. A novel grading scale was then proposed and used in this study for the same. We prospectively collected data and retrospectively analyzed 425 patients undergoing robotic-assisted laparoscopic prostatectomy (RALP) at a high-volume center by a single surgeon.

Results:

At 1 year of follow-up, it was found that age, laterality of nerve preservation, weight of prostate, and the surgeon-assigned grading were all statistically significant independent predictors of return of potency in terms of satisfactory penetrative intercourse >50% of times and Sexual Health Inventory for Men ≥17. However, prostate-specific antigen was found not to be a predictor of the same.

Conclusions:

Intraoperative physician-assigned grading was found to be the single most significant predictor of the return of potency at 1-year post-RALP.

Chinese herbal medicine for postpartum constipation: a protocol of systematic review and meta-analysis

INTRODUCTION

Constipation is one of the most common gastrointestinal symptoms in postpartum mothers. The choice of treatments for postpartum constipation remains a challenging clinical problem. Chinese herbal medicine has become increasingly popular as an alternative therapy for constipation. This systematic review aims to evaluate the efficacy and safety of Chinese herbal medicine for postpartum constipation.

METHODS AND ANALYSIS

We will search PubMed (1946 to present), EMBASE (1974 to present), Cochrane Central Register of Controlled Trials (all years), Web of Science (1900 to present), Chinese Biomedical Literatures Database (1978 to present), China National Knowledge Infrastructure (1979 to present) and WANFANG data (1998 to present) to identify any eligible study. No restriction will be put on the language, publication date or status of the study. The primary outcome will be the spontaneous bowel movement. Secondary outcomes will be stool consistency, quality of life, transit time, relief of constipation symptoms and adverse events. We will perform the meta-analysis when more than one trial examines the same intervention and outcomes with comparable methods in similar populations. If the heterogeneity is not significant statistically (p>0.10 or I2<50%), the fixed-effect model will be built to estimate the overall intervention effects. Otherwise, the random-effect model will be used to provide more conservative results.

ETHICS AND DISSEMINATION

No ethical issues are foreseen because no primary data will be collected. The results will be published in a peer-reviewed scientific journal.

PROSPERO REGISTRATION NUMBER

CRD42018093741.

Anatomical, surgical and technical factors influencing continence after radical prostatectomy

Radical prostatectomy (RP) is the most frequent treatment with curative intent performed for prostate cancer to date. Different surgical approaches (perineal, transperitoneal, and extraperitoneal) and techniques (laparoscopic and robot assisted) have been described to increase the efficiency and potentially diminish the postoperative complications of this procedure. The aim of this narrative review is to investigate and define the factors that influence postprostatectomy urinary continence. We highlighted the anatomical landmarks and the modifications of surgical techniques aimed at improving the continence rates and thus, patient quality of life. After RP, the long-term continence rates range from 84% to 97%. In order to achieve good continence rates, a careful dissection along with meticulous anatomical reconstruction is required. To this end, a detailed knowledge of the periprostatic anatomy is mandatory.

Neuro-anatomic basis of potency recovery after radical prostatectomy: an expert's point of view

INTRODUCTION

From 25% to 95% of those who have undergone radical prostatectomy (RP) report erectile dysfunction 12 months after surgery. We attempt a review of the available evidence regarding the anatomy of the cavernous nerves and the surgical refinements to enhance sexual function recovery after surgery.

EVIDENCE ACQUISITION

The PubMed/Medline database was searched. Duplicates were removed. Studies were selected by the authors according to the aim of the present review.

EVIDENCE SYNTHESIS

The cavernous nerves are deemed responsible for erections, but their exact function is still a matter of debate. They do not necessarily have the same distribution in all individuals: in most the cases, these nerves are located posterolaterally, however, it is not uncommon to find some fibers on the anterolateral aspects of the prostate, especially towards the apex. Several technical strategies were proposed in order to intraoperatively identify and spare the neurovascular bundles: despite all efforts, clinical results are still only partially satisfying.

CONCLUSIONS

The recovery of potency is one of the most unpredictable outcomes after RP. The advent of the robotic surgical system seems to have brought a trend towards a faster recovery of erectile function.

Indications, surgical technique, and long-term results of nerve sparing

Radical prostatectomy is frequently performed as a curative approach for clinically localized prostate cancer. In order to reduce the adverse effects of this operation on erectile function, preservation of neurovascular bundles was introduced as part of this operation. The decision of nerve sparing must be carefully tailored in each patient according to the stage of the disease. Patient selection has a critical importance in performing nerve sparing radical prostatectomy. In organ-confined cancers a nerve sparing surgery can be performed in the majority of the cases without jeopardizing tumor control. Individualized decision making in each case may allow more patients to receive a nerve sparing approach, and therefore, better functional outcomes. However, it continues to be difficult to predict postoperative functional outcomes accurately due to many influencing factors.