Nightly vs on-demand sildenafil for penile rehabilitation after minimally invasive nerve-sparing radical prostatectomy: results of a randomized double-blind trial with placebo

The Cavernous Nerve Injury Rat Model: A Pictorial Essay on Post-Radical Prostatectomy Erectile Dysfunction Research

Understanding and addressing post-radical prostatectomy (RP) erectile dysfunction (ED) is of paramount importance for clinicians. Cavernous nerve (CN) injury rat model studies have provided consistently promising experimental data regarding regaining erectile function (EF) after nerve damage-induced ED. However, these findings have failed to translate efficiently into clinical practice, with post-RP ED therapeutic management remaining cumbersome and enigmatic. This disparity highlights the need for further standardization and optimization of the elaborate surgical preparation protocols and multifaceted reporting parameters involved in reliable CN injury rat model experimentation. Even so, despite its technical complexity, this animal model remains instrumental in exploring the functional implications of RP, i.e., surgical lesions of the neurovascular bundles (NVBs). Herein, besides cavernous nerve (CN) dissection, injury, and electrostimulation, multiple pressure measurements, i.e., mean arterial pressure (MAP) and intra-cavernosal pressure (ICP), must also be achieved. A transverse cervical incision allows for carotid artery cannulation and MAP measurements. Conversely, ICP measurements entail circumcising the penis, exposing the ischiocavernous muscle, and inserting a needle into the corporal body. Finally, using an abdominal incision, the prostate is revealed, and the major pelvic ganglia (MPG) and CNs are dissected bilaterally. Specific surgical techniques are used to induce CN injuries. Herein, we provide a narrative and illustrative overview regarding these complex experimental procedures and their particular requirements, reflecting on current evidence and future research perspectives.

Reviving intimacy: Penile rehabilitation strategies for men after prostate cancer treatment

There have been considerable advances in the field of penile rehabilitation for upwards of 90% of men adversely affected by either short-term or long-term erectile dysfunction after definitive prostate cancer treatment. Despite the evolving landscape of treatment modalities for penile rehabilitation, there is a lack of consensus in the urologic community on the best therapies due to the level of evidence and efficacies of the current and emerging offerings. This review of current and next-generation interventions provides a practical approach to the myriad of data to make a better-informed decision based on the pathophysiology and highest-quality evidence available.

Efficacy of a Red-Light Controllable Nitric Oxide Releaser for Neurogenic Erectile Dysfunction: A Study Using a Rat Model of Cavernous Nerve Injury

PURPOSE

Neurogenic erectile dysfunction (ED) is a common side effect of radical prostatectomy (RP) because of cavernous nerve damage. In these patients, the production of nitric oxide (NO), which is important for erection, is decreased in the corpus cavernosum. Therefore, NO donors are useful for post-RP ED. However, short half-life and systemic side effects are problems of NO application in ED therapy. To avert these problems, we developed a red-light controllable NO releaser, NORD-1. This study aimed to investigate the effect of NORD-1 and red-light irradiation on neurogenic ED using a rat model of bilateral cavernous nerve injury (BCNI).

MATERIALS AND METHODS

BCNI and sham operations were conducted on 8-week-old rats. After 4 weeks, erectile function was evaluated using changes in intracavernous pressure (ICP) during electrostimulation of the cavernous nerve. ICP was measured under three conditions; without NORD-1 and red-light irradiation, with NORD-1 and without red-light irradiation, and with NORD-1 and red-light irradiation. SiR650 which absorbs red-light but does not release NO was used for the negative control. After the experiment, localization of NORD-1 was observed using a microscope.

RESULTS

Erectile function in a BCNI rat model was significantly decreased compared to sham-operated rats (p<0.05). After injecting NORD-1 into the penis, erectile function did not change without red-light irradiation. However, the combination of NORD-1 and red-light irradiation significantly improved erectile function (p<0.05) without affecting systemic arterial pressure. In contrast, when SiR650 was used, erectile function did not change in all three conditions. NORD-1 was detected only in the corpus cavernosum and not in the urethra and dorsal vein.

CONCLUSIONS

NORD-1 combined with red-light irradiation is effective for ED induced by cavernous nerve injury. This treatment may have low risks of hypotension and urinary incontinence, and it can replace the current treatment for post-RP ED.

Ultrasound-targeted microbubble destruction mediates PDE5i/NO integration for cavernosum remodeling and penile rehabilitation

Erectile dysfunction (ED) caused by cavernous nerve injury (CNI) is refractory to heal mainly ascribed to the adverse remodeling of the penis induced by ineffectual microvascular perfusion, fibrosis, and neurotrophins scarcity in cavernosum. Phosphodiesterase type V inhibitors (PDE5i) have been regarded as an alternative candidate drug for avoiding penile neuropathy. However, the therapeutic efficacy is severely limited due to poor accumulation under systemic medication and endogenous nitric oxide (NO) deficiency in cavernosum. Herein, an innovative liposomal microbubble (MB) loaded with both Sildenafil (one of PDE5i) and NO was designed. Ultrasound-targeted MB destruction (UTMD)-mediated efficient release and integration erectogenic agents into corpus cavernosum with high biosafety. On a bilateral CNI rat model, the multifunctional MB-cooperated UTMD improved microvascular perfusion in penis, simultaneously, alleviated hypoxia and oxidative stress, indicating successful activation of NO-cyclic guanosine monophosphate pathway. Also, evaluation of the endothelial/muscular composition, intracavernosal pressure, and neural integrity in the penis proved that coordinated intervention reversed the abnormal structural remodeling and promoted the recovery of functional erection. Our work demonstrates that MB loading Sildenafil and NO combined with UTMD hold great promise to "awaken" the efficacy of PDE5i in neurogenic ED, which provided a superior option for ensuring penile rehabilitation.

Comparison of the efficacy of the early LI-SWT plus daily tadalafil with daily tadalafil only as penile rehabilitation for postprostatectomy erectile dysfunction

This study compares the efficacy of the early low-intensity shock wave therapy (LI-SWT) plus daily tadalafil with daily tadalafil only therapy as penile rehabilitation for postprostatectomy erectile dysfunction in patients with prostate cancer who underwent bilateral interfascial nerve-sparing radical prostatectomy (robotic or open). From April 2019 to March 2021, 165 patients were enrolled, and 80 of them successfully completed this prospective study. Daily tadalafil were administered to all the patients. LI-SWT consisted of a total of six sessions. Each session was performed on days 4, 5, 6, and 7, and on the second and fourth weeks after surgery. Each LI-SWT session consisted of 300 shocks at an energy density of 0.09 mJ/mm2 and a frequency of 120 shocks per minute that were delivered at each of the five treatment points for 15 min. Thirty-nine patients were treated with tadalafil-only (group A) while 41 were treated with tadalafil and LI-SWT simultaneously (group B). At postoperative 6 months, the proportion of patients with erection hardness scores (EHS) ≥ 3 (4/39 vs. 12/41) was significantly higher in group B (p = 0.034), and LI-SWT was the only independent factor for predicting EHS ≥ 3 (OR, 3.621; 95% CI, 1.054-12.437; p = 0.041). There were no serious side effects related to early LI-SWT. Early LI-SWT plus daily tadalafil therapy as penile rehabilitation for postprostatectomy erectile dysfunction is thought to be more efficacious than tadalafil only. Further large-scaled randomized controlled trials will be needed to validate these findings.

Implantation of skin-derived precursor Schwann cells improves erectile function in a bilateral cavernous nerve injury rat model

BACKGROUND

This study was conducted to investigate the therapeutic potential of the skin-derived precursor Schwann cells for the treatment of erectile dysfunction in a rat model of bilateral cavernous nerve injury.

RESULTS

The skin-derived precursor Schwann cells-treatment significantly restored erectile functions, accelerated the recovery of endothelial and smooth muscle tissues in the penis, and promoted nerve repair. The expression of p-Smad2/3 decreased after the treatment, which indicated significantly reduced fibrosis in the corpus cavernosum.

CONCLUSIONS

Implantation of skin-derived precursor Schwann cells is an effective therapeutic strategy for treating erectile dysfunction induced by bilateral cavernous nerve injury.

Spider silk erectile nerve reconstruction in robot-assisted radical prostatectomy: a first-in-men feasibility analysis

PURPOSE

To investigate the safety and feasibility of spider silk interposition for erectile nerve reconstruction in patients undergoing robotic radical prostatectomy (RARP).

METHODS

The major-ampullate-dragline from Nephila edulis was used for spider silk nerve reconstruction (SSNR). After removal of the prostate with either uni- or bilateral nerve-sparing, the spider silk was laid out on the site of the neurovascular bundles. Data analysis included inflammatory markers and patient reported outcomes.

RESULTS

Six patients underwent RARP with SSNR. In 50% of the cases, only a unilateral nerve-sparing was performed, bilateral nerve-sparing could be performed in three patients. Placement of the spider silk conduit was uneventful, contact of the spider silk with the surrounding tissue was mostly sufficient for a stable connection with the proximal and distal ends of the dissected bundles. Inflammatory markers peaked until postoperative day 1 but stabilized until discharge without any need for antibiotic treatment throughout the hospital stay. One patient was readmitted due to a urinary tract infection. Three patients reported about erections sufficient for penetration after three months with a continuous improvement of erectile function both after bi- and unilateral nerve-sparing with SSNR up to the last follow-up after 18 months.

CONCLUSION

In this analysis of the first RARP with SSNR, a simple intraoperative handling without major complications was demonstrated. While the series provides evidence that SSNR is safe and feasible, a prospective randomized trial with long-term follow-up is needed to identify further improvement in postoperative erectile function due to the spider silk-directed nerve regeneration.

Penile Rehabilitation after Prostate Cancer Treatment: Which Is the Right Program?

The management of sexual complications after treatment of localized prostate cancer, such as erectile dysfunction, changes in the length of the penis, pain during sexual intercourse, and lack of orgasm, is still an unsolved problem with an important impact on patients’ quality of life. In this review, we summarize the current scientific literature about the rehabilitation of erectile dysfunction after prostate cancer treatment. The therapy for penile rehabilitation includes different types of treatments: the combination of phosphodiesterase type 5 inhibitors (PDE5-I) and the vacuum erectile device (VED) are considered first-line treatment options. When therapy begins, the duration of treatment, the dosage and the drug used all play very important roles in the treatment outcome. Intracavernous injection (ICI) therapy represents the second-line option for patients ineligible for PDE5-I therapy. Technological development has led to the emergence of devices for the stimulation of the penis without the use of drugs, such as penile vibratory stimulation (PVS) for stimulation of ejaculation in spinal cord injury and low-intensity extracorporeal shockwave therapy (LIESWT). The rapid diffusion of the latter, thanks to its easy use, attains good results without side effects. The panorama of penile rehabilitation after PC treatments is vast and many studies are needed, especially on new technologies, to find the best therapeutic regimen possible, personalized to the patient’s characteristics and the type of treatment for PC.

Consensus of Experts on the Treatment of Sexual Dysfunction after Surgery for Prostate Cancer in Taiwan

According to the Taiwan Cancer Report, in 2018, prostate cancer was one of the top five cancers reported in men. Each year, many patients with prostate cancer undergo radical prostatectomy (RP) therapy. One of the most common RP complications is erectile dysfunction (ED). Although consensus guidelines for the management of sexual dysfunction after prostate cancer surgery have been developed for many Western and Asian countries, no such clinical practice guidelines have been developed for Taiwan. The consensus opinions expressed in this article were discussed by numerous experienced physicians in Taiwan, based on both existing international guidelines and their individual experiences with clinical trials and providing advice to clinical physicians on how to inform patients of the risk of ED prior to surgery. This review also discusses how recovery and rehabilitation may be affected by socioeconomic status, the existence of an intimate relationship, comorbidities, or the need for cancer adjuvant therapy and how to determine rehabilitation goals and provide appropriate treatments to assist in the recovery of both short- and long-term sexual function.

Efficacy and Safety of Udenafil Once Daily in Patients with Erectile Dysfunction after Bilateral Nerve-Sparing Robot-Assisted Laparoscopic Radical Prostatectomy: A Randomized, Double-Blind, Placebo-Controlled Study

PURPOSE

To evaluate the efficacy and safety of udenafil 75 mg once daily in patients with erectile dysfunction following bilateral nerve-sparing robot-assisted laparoscopic radical prostatectomy (BNS-RALP).

MATERIALS AND METHODS

A multi-center, prospective, randomized, controlled, double-blind study was conducted. Among patients with localized prostate cancer with international index of erectile function-erectile function domain (IIEF-EF) score of 18 or higher before BNS-RALP, those who developed postoperative erectile dysfunction (IIEF-EF score 14 or less at 4 weeks after BNS-RALP) were enrolled. Enrolled patients were randomly assigned to the udenafil 75 mg daily group or the placebo group in a 2:1 ratio. Each subject was followed up at 8 weeks (V2), 20 weeks (V3), and 32 weeks (V4) to evaluate the efficacy and safety of udenafil.

RESULTS

In all, 101 patients were screened, of whom 99 were enrolled. Of the 99 patients, 67 were assigned to the experimental group and 32 to the control group. Ten (14.93%) patients in the experimental group and 10 (31.25%) in the control group dropped out of the study. After 32 weeks of treatment, IIEF-EF score of 22 or higher was seen in 36.51% (23/63) of patients in the experimental group and 13.04% (3/23) patients in the control group (p=0.021). The proportion of patients with IIEF-EF improvement of 25% or more compared to the baseline was 82.54% (52/63) in the experimental group and 62.96% (17/27) in the control group (p=0.058).

CONCLUSIONS

Udenafil 75 mg once daily after BNS-RALP improved the erectile function without any severe adverse effects.

An update on the current status and future prospects of erectile dysfunction following radical prostatectomy

BACKGROUND

Radical prostatectomy (RP) and radiation treatment are standard options for localized prostate cancer. Even though nerve-sparing techniques have been increasingly utilized in RP, erectile dysfunction (ED) due to neuropraxia remains a frequent complication. Erectile function recovery rates after RP remain unsatisfactory, and many men still suffer despite the availability of various therapies.

OBJECTIVE

This systematic review aims to summarize the current treatments for post-RP-ED, assess the underlying pathological mechanisms, and emphasize promising therapeutic strategies based on the evidence from basic research.

METHOD

Evaluation and review of articles on the relevant topic published between 2010 and 2021, which are indexed and listed in the PubMed database.

RESULTS

Phosphodiesterase type 5 inhibitors, intracavernosal and intraurethral injections, vacuum erection devices, pelvic muscle training, and surgical procedures are utilized for penile rehabilitation. Clinical trials evaluating the efficacy of erectogenic drugs in this setting are conflicting and far from being conclusive. The use of androgen deprivation therapy in certain scenarios after RP further exacerbates the already problematic situation and emphasizes the need for effective treatment strategies.

CONCLUSION

This article is a detailed overview focusing on the pathophysiology and mechanism of the nerve injury developed during RP and a compilation of various strategies to induce cavernous nerve regeneration to improve erectile function (EF). These strategies include stem cell therapy, gene therapy, growth factors, low-intensity extracorporeal shockwave therapy, immunophilins, and various pharmacological approaches that have induced improvements in EF in experimental models of cavernous nerve injury. Many of the mentioned strategies can improve EF following RP if transformed into clinically applicable safe, and effective techniques with reproducible outcomes.

Focusing on sexual rehabilitation besides penile rehabilitation following radical prostatectomy is important

Erectile dysfunction is commonly reported after radical prostatectomy. Besides the loss of erections, sexual life after prostatectomy is impacted by urinary incontinence, orgasmic dysfunction, and psychological stress. In this review, we describe classical medical therapies used for erectile function rehabilitation such as PDE5 inhibitors and injection therapy. A vast amount of data support the idea of focusing on restoration of sexual function on top of erectile function after prostatectomy. The important strategies described to rehabilitate sexual function include pelvic floor muscle therapy, couple therapy, appropriate preoperative counseling, and focusing on non-penetrative alternatives. A multidisciplinary approach and including the partner is important. Erectile function alone is not sufficient for satisfactory sexual experience and may not be used as a proxy for sexual quality of life. Adding full-spectrum sexual rehabilitation to a standard penile rehabilitation regimen has the highest chances of obtaining satisfactory sexual outcomes in men and their partners after radical prostatectomy.

Impact of penile rehabilitation with phosphodiesterase-5 inhibitors on recovery of erectile function in patients undergoing robot-assisted radical prostatectomy: A propensity score-matched analysis

OBJECTIVE

To investigate the impact of penile rehabilitation on the recovery of erectile function after robot-assisted radical prostatectomy.

METHODS

Patients who underwent robot-assisted radical prostatectomy in our department from 2010 to 2019 were included. For penile rehabilitation, a phosphodiesterase-5 inhibitor (tadalafil 20 mg) was administered twice a week for 1-6 months postoperatively. The International Index of Erectile Function questionnaire (question 1 and erectile function domain) and the Expanded Prostate Cancer Index Composite questionnaire (sexual function) were used.

RESULTS

After propensity score matching, there were 79 patients in the penile rehabilitation group and 79 patients in the non-penile rehabilitation group. There was no significant difference in baseline characteristics between the two groups. Significantly higher scores were seen in the penile rehabilitation group compared with the non-penile rehabilitation group at postoperative 3, 6 and 9 months in the International Index of Erectile Function questionnaire-question 1, at 3, 6, 9 and 12 months in erectile function domain, and at 3, 6, 12 and 24 months in Expanded Prostate Cancer Index Composite questionnaire sexual function (P < 0.05). There were significant improvements in the erectile recovery rate in the penile rehabilitation group compared with the non-penile rehabilitation group in the nerve sparing (P = 0.006) and partial nerve sparing (P = 0.037) groups.

CONCLUSIONS

The present findings suggest that robot-assisted radical prostatectomy patients who undergo not only nerve sparing, but also those who undergo patial nerve sparing could benefit from penile rehabilitation using a phosphodiesterase-5 inhibitor.

Phosphodiesterase type-5 inhibitors for erectile dysfunction following nerve-sparing radical prostatectomy: A network meta-analysis

BACKGROUND

To verify which phosphodiesterase type 5 inhibitors (PDE5is) strategy is better for erectile dysfunction (ED) following nerve-sparing radical prostatectomy (NSRP).

METHODS

This systematic literature search was conducted in MEDLINE, Web of Science and Cochrane Central Register of Controlled Trials database to identify eligible studies from the startup of these databases to 1 November, 2019. The ED recovery rate was the main outcome. Traditional pair-wise meta-analysis and multivariate random-effects network meta-analysis (NMA) were performed to explore direct and indirect comparisons, respectively. The surface under the cumulative ranking (SUCRA) probabilities was used to evaluate the efficacy of treatments.

RESULTS

A total of 14 randomized controlled trials with four kinds of PDE5is were included. Further pooled evidence suggested that PDE5is followed by NSRP had a benefit for penile rehabilitation compared to placebo using traditional pair-wise meta-analyses. Our NMA showed that Avanafil 200 mg on demand might be most likely to be the best treatment option according to the first rank of SUCRA both in NMA (SUCRA 83.5) and sensitivity analysis (SUCRA 90.2).

CONCLUSION

Avanafil 200 mg on demand has the highest probability of being the best intervention among PDE5is in treating ED following NSRP. However, more randomized controlled trials are needed to validate this in consideration of the published data regarding Avanafil is relatively small scale.

Comprehensive approach for preserving cavernous nerves and erectile function after radical prostatectomy in the era of robotic surgery

A nerve-sparing procedure during robot-assisted radical prostatectomy has been considered one of the most important techniques for preserving postoperative genitourinary function. The reason is that adequate nerve-sparing procedures could preserve both erectile function and lower urinary tract function after surgery. When a nerve-sparing procedure is carried out, the cavernous nerves themselves cannot be visualized, despite the magnified viewing field during robot-assisted radical prostatectomy. Thus, nerve-sparing procedures have been considered challenging operations, even now. However, because not all surgeons have carried out a sufficient number of nerve-sparing procedures, the development of new nerve-sparing procedures or new methods for mapping the cavernous nerves is required. Recently, various new operative techniques, for example, Retzius-sparing robot-assisted radical prostatectomy, transvesical robot-assisted radical prostatectomy and retrograde release of neurovascular bundle technique during robot-assisted radical prostatectomy, have been developed. In addition, new surgical devices, for example, biological/bioengineering solutions for cavernous nerve protection and devices for identifying the cavernous nerves during radical prostatectomy, have developed to preserve the cavernous nerves. In contrast, limitations or problems in preserving cavernous nerves and postoperative erectile function have become apparent. In particular, the recovery rate of erectile function, the positive surgical margin rate at the site of nerve-sparing and the indications for nerve sparing have become obvious with the accumulation of much evidence. Furthermore, predictive factors for postoperative erectile function after nerve-sparing procedures have also been clarified. In this article, the importance of a comprehensive approach for early recovery of erectile function in the robot-assisted radical prostatectomy era is discussed.

Generating comprehensive comparative evidence on various interventions for penile rehabilitation in patients with erectile dysfunction after radical prostatectomy: a systematic review and network meta-analysis

Background

We aim to present a comprehensive comparison of various treatments in the management of penile recovery after radical prostatectomy (RP) and provide recommendations for future research.

Methods

Literature search of electronic databases including PubMed, the Cochrane Library, Embase, PsycInfo, and Web of Science, and manual retrieval were conducted from inception through March 2020. “Erectile dysfunction” and “prostatectomy” were used as the Mesh terms. The patients, intervention, comparison, outcome, and study design (PICOS) approach were used to define study eligibility. Two authors independently selected studies, evaluated the methodological quality, and extracted data using Cochrane Collaboration’s tools. The data analysis was completed by STATA version 14.2.

Results

A total of 24 studies with 3,500 patients were incorporated in the final analysis after screening 6,131 records. Our findings indicated that vacuum constriction devices (VCD) ranked 1st which meant that patients in VCD group had the best effect regarding mean IIEF scores within 3 months after RP, and no significant difference was observed between VCD and VCD with 20 mg/day tadalafil (V20DT) (MD: 5.44; 95% CI: −0.81 to 11.69). VCD and 50 mg/day sildenafil (VC50DS) showed superiority over 50 mg/day sildenafil (50DS) (MD: 3.75; 95% CI: 2.74–4.76) and intraurethral alprostadil 125–250 µg (MD: 3.05; 95% CI: 0.38 to 5.72), respectively. Moreover, V20DT showed significant superiority over the other interventions for ≥6 months mean International Index Erectile of Function (IIEF) scores after RP. Monotherapy appeared to have similar efficacy in terms of mean IIEF scores and proportion of patients return to baseline, and the effect of phosphodiesterase type 5 inhibitors (PDE5is) did not seem to be affected by the patterns of administration (regular or on demand).

Conclusions

The combination therapy showed certain advantages over monotherapy, and we recommended the combination of VCD and PDE5is to be considered in the clinical management of penile rehabilitation after RP.

Phosphodiesterases 5 Inhibitors and Erectile Dysfunction Recovery after Pelvic Surgery: Future Perspectives for New Drugs and New Formulations

BACKGROUND

Phosphodiesterase 5 inhibitors (PDE5I) represent the first-line treatment in the management of post-operative erectile dysfunction (ED) after pelvic oncological surgery. The aim of our study is to evaluate the available evidence on the efficacy of PDE5Is, including new formulations and penile rehabilitation post-pelvic surgery.

EVIDENCE ACQUISITION

A systematic review of the literature was performed until May 2020. The following databases were searched: Scopus, Medline and Web of Science. The MeSH search was conducted by combining the following terms: 'erectile dysfunction', 'radical prostatectomy' 'pelvic' 'bladder' 'phosphodiesterase' inhibitors' 'avanafil' 'sildenafil' 'tadalafil' 'lodenafil' 'mirodenafil' 'udenafil' 'vardenafil' 'sublingual' 'orodispersible' 'penile' 'rehabilitation'.

EVIDENCE SYNTHESIS

Sildenafil, Tadalafil, vardenafil and Avanafil improve EF compared with placebo in men with all levels of ED severity after radical prostatectomy with good tolerability. No specific recommendations can be suggested regarding the superiority of a drug over the other. The optimal dose, continuous vs. on-demand and duration of treatment, is still under investigation. In vitro and preclinical studies suggest the possible role for lodenafil, mirodenafil and oro-dispersible formulations in patients undergoing oncological pelvic surgery. Few studies demonstrated the efficacy of udenafil in improving ED after rectal surgery or radical prostatectomy. Complete recovery of EF after surgery is still an unmet need in the field of penile rehabilitation after pelvic surgery.

CONCLUSION

PDE5Is have a crucial role in the management of post pelvic surgery of ED. New drugs and new formulations have shown excellent results in patients with ED; however, data in patients after surgery is still scarce. Further well designed RCT should clarify the role of these new compounds and oro-dispersible formulations in the management of ED in patients undergoing pelvic surgery.

Current management strategy of treating patients with erectile dysfunction after radical prostatectomy: a systematic review and meta-analysis

The aim of this study is to present a summary of current evidence concerning the various treatments in the management of penile rehabilitation after radical prostatectomy (RP) and provide recommendations for future research. Randomized controlled trials (RCTs) were identified from electronic databases including PubMed, the Cochrane Library, Embase, and Web of Science from inception through March 2020 with no limitation to language. Comparable data from each study were combined in a meta-analysis where possible, otherwise data were synthesized narratively. The data analysis was completed by Review Manager version 5.3. A total of 39 RCTs were included in this study. At present, phosphodiesterase type 5 inhibitors (PDE5is) remain the first-line treatment for patients with erectile dysfunction (ED) after RP. Compared with the placebo group, patients in regular PDE5is group (mean difference (MD): 0.76; 95% confidence interval (CI): 1.69-4.44; p < 0.0001) and on demand group (MD: 3.92; 95% CI: 2.95-4.88; p < 0.00001) had a significantly higher mean Erectile Function domain of the International Index of Erectile Function (IIEF-EF) scores within 3 months after RP. As for the proportion of IIEF-EF ≥ 22, patients in regular PDE5is group and on demand PDE5is group had significantly higher proportion than those in placebo group 6 months after RP, and the odds ratios were 1.87 (95% CI: 1.32-2.66; p = 0.0005) and 2.17 (95% CI: 1.20-3.93; p = 0.01), respectively. No significant difference was observed between regular PDE5is group and on demand group regardless of mean IIEF-EF score or the proportion of IIEF-EF ≥ 22. Intracorporeal injection therapy seemed to have similar efficacy to PDE5is. The International Index of Erectile Function-5 items (IIEF-5) scores were significantly higher in vacuum constriction devices group than control group at 6-9 months after RP (MD: 6.70, 95% CI: 2.30-11.10, p = 0.003) with great between-study heterogeneity (p = 0.06, I² = 72%). The other therapeutics including low-intensity extracorporeal shockwave therapy, statin therapy, psychotherapy interventions, and pelvic floor muscle training plus electrical stimulation showed certain improvement on erectile function. We found that the combination therapy showed certain advantages over monotherapy. Currently, PDE5is-based combination therapy remains the mainstream treatment for ED after RP. Intracorporeal injection therapy and vacuum therapy could be served as alternative treatments if PDE5is are ineffective and contraindicated.

Benefits of erectile function recovery programs after radical prostatectomy (Review)

Radical prostatectomy is one of the most frequent therapeutic options used for the management of patients diagnosed with prostate cancer. Normal erectile function after radical prostatectomy is a great problem for numerous patients and a real challenge for urologists worldwide. The advancements that have been made over the years in terms of minimally invasive surgery, as well as in terms of surgical techniques, have reduced the incidence of erectile dysfunction, but even so, its rate remains high and the post-operative recovery of erectile function is a long and costly process. Phosphodiesterase 5 inhibitors have provided excellent results and have become the first-line treatment for these patients, followed by intracavernous injections with alprostadil. Several studies have underlined the impact of phosphodiesterase 5 inhibitors in terms of preventing the fibrotic changes that are responsible for the irreversible erectile dysfunction. The general opinion is that an erectile function recovery process should be started as soon as possible after surgery to prevent the negative effects of neuropraxia.

Erectile Dysfunction: A Primer for in Office Management

Introduction: Optimizing erectile dysfunction (ED) remains a clinically significant endeavor as insufficient outcomes from oral, injectable and even surgical approaches to treatment remain less than ideal. In this report, we integrate evolving knowledge and provide an algorithmic approach for the clinician to fine-tune management. Methods: We performed a PubMed and Medline search of Erectile Dysfunction treatment optimization, enhanced patient efficacy for ED, and why men fail ED treatment. All relevant papers for the past two decades were reviewed. Results: Establishing the goals and objectives of the patient and partner while providing detailed instructions for treatment can minimize failures and create an environment that allows treatment optimization. A thorough work-up may identify reversible or contributing causes. We identified several areas where treatment of ED could be optimized. These include; management of associated medical conditions, lifestyle improvements, PDE5 inhibitor prescription strategies, management of hypogonadism and the initiation of intracavernosal injection therapy (ICI). Conclusions: In our view, once a man presents for help to the clinician, use of the simple strategies identified in this review to optimize the tolerability, safety and effectiveness of the selected treatment should result in enhanced patient and partner satisfaction, with improved outcomes.

Sildenafil in postprostatectomy erectile dysfunction (perspective)

Erectile dysfunction (ED) is a common side effect to radical prostatectomies, even with nerve-sparing procedures. To ameliorate the problem so-called "penile rehabilitation" programs have been developed. The most widely used method of this is subscribing sildenafil or other PDE5-inhibitors to patients following surgery. This is based on a theory that these drugs may increase penile oxygenation and provide antiapoptotic factors (primarily NO and cGMP), thus protecting the penile tissue in a period with reduced nerve function following the surgery. Preclinical studies have confirmed the potential of sildenafil in this context and early human trials have suggested that a steady ingestion of sildenafil might protect the structural integrity of the penis. However, subsequent well-designed trials have not been able to confirm the initial findings. This fits well with sildenafil's mechanism of action because it does not actually induce erections or the production of either nitric oxide or cGMP. Rather, the drug enhances effects of an erectile response induced by neurotransmitters from the cavernous nerves. Therefore, sildenafil should no longer be offered as a sole means of penile rehabilitation. Rather, more research is needed, and clinicians need to apply a broader concept of sexual rehabilitation in postprostatectomy ED.

Perplexity of penile rehabilitation following radical prostatectomy

Radical prostatectomy has significantly improved prostate cancer survival rates but continues to have a negative impact on the patient's erectile function (EF). In attempts to improve erectile dysfunction (ED), clinicians have incorporated different treatment modalities to restore EF. Penile rehabilitation consists of understanding the mechanisms that affect post-prostatectomy EF and utilizing pharmacologic agents, devices, and interventions to promote the male sexual function. This article aims to summarize the available scientific research involving penile rehabilitation. Even though the current literature lacks to prove its irrefutable effectiveness, penile rehabilitation has a positive impact at the molecular and cellular levels, and it is widely adopted in clinic practices.

Penile rehabilitation for postprostatectomy erectile dysfunction

BACKGROUND

Despite efforts to preserve the neurovascular bundles with nerve-sparing surgery, erectile dysfunction remains common following radical prostatectomy. Postoperative penile rehabilitation seeks to restore erectile function but results have been conflicting.

OBJECTIVES

To evaluate the effects of penile rehabilitation strategies in restoring erectile function following radical prostatectomy for prostate cancer.

SEARCH METHODS

We performed a comprehensive search of multiple databases (CENTRAL, MEDLINE, Embase), the Cochrane Library, Web of Science, clinical trial registries (ClinicalTrials.gov, International Clinical Trials Registry Platform) and a grey literature repository (Grey Literature Report) from their inception through to 3 January 2018. We also searched the reference lists of other relevant publications and abstract proceedings. We applied no language restrictions.

SELECTION CRITERIA

We included randomised or quasi-randomised trials with a parallel or cross-over design.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Two review authors independently screened the literature, extracted data, assessed risk of bias and rated quality of evidence according to GRADE on a per-outcome basis. Primary outcomes were self-reported potency, erectile function measured by validated questionnaires (with potency defined as an International Index of Erectile Function (IIEF-EF) score of 19 or greater and or an IIEF-5 of score of 17 or greater) and serious adverse events. For all quality of life assessments on a continuous scale, higher values indicated better quality of life.

MAIN RESULTS

We included eight randomised controlled trials with 1699 participants across three comparisons. This abstract focuses on the primary outcomes of this review only.Scheduled phosphodiesterase type 5 inhibitors (PDE5I) versus placebo or no treatmentScheduled PDE5I may have little or no effect on short-term (up to 12 months) self-reported potency (risk ratio (RR) 1.13, 95% confidence interval (CI) 0.91 to1.41; very low quality evidence), which corresponds to 47 more men with self-reported potency per 1000 (95% CI 33 fewer to 149 more) and short-term erectile function as assessed by a validated instrument (RR 1.11, 95% CI 0.80 to 1.55; very low quality evidence), which corresponds to 28 more men per 1000 (95% CI 50 fewer to 138 more), but we are very uncertain of both of these findings. Scheduled PDE5I may result in fewer serious adverse events compared to placebo (RR 0.32, 95% CI 0.11 to 0.94; low quality evidence), though this does not appear biologically plausible and may represent a chance finding. We are also very uncertain of this finding. We found no long-term (longer than 12 months) data for any of the three primary outcomes.Scheduled PDE5I versus on-demand PDE5I Daily PDE5I appears to result in little to no difference in both short-term and long-term (greater than 12 months) self-reported potency (short term: RR 0.97, 95% CI 0.62 to 1.53; long term: RR 1.00, 95% CI 0.60 to 1.67; both very low quality evidence); this corresponds to nine fewer men with self-reported short-term potency per 1000 (95% CI 119 fewer to 166 more) and zero fewer men with self-reported long-term potency per 1000 (95% CI 153 fewer to 257 more). We are very uncertain of these findings. Daily PDE5I appears to result in little to no difference in short-term and long-term erectile function (short term: RR 1.00, 95% CI 0.65 to 1.55; long term; RR 0.74, 95% CI 0.48 to 1.14; both very-low quality evidence), which corresponds to zero men with short-term erectile dysfunction per 1000 (95% CI 80 fewer to 125 more) and 119 fewer men with long-term erectile dysfunction per 1000 (95% CI 239 fewer to 64 more). We are very uncertain of these findings. Scheduled PDE5I may result in little or no effects on short-term adverse events (RR 0.69 95% CI 0.12 to 4.04; very low quality evidence), which corresponds to seven fewer men with short-term serious adverse events (95% CI 18 fewer to 64 more), but we are very uncertain of these findings. We found no long-term data for serious adverse events.Scheduled PDE5I versus scheduled intraurethral prostaglandin E1At short-term follow-up, daily PDE5I may result in little or no effect on self-reported potency (RR 1.10, 95% CI 0.79, to 1.52; very low quality evidence), which corresponds to 46 more men per 1000 (95% CI 97 fewer to 241 more). Daily PDE5I may result in a small improvement of erectile function (RR 1.64, 95% CI 0.84 to 3.20; very low quality evidence), which corresponds to 92 more men per 1000 (95% CI 23 fewer to 318 more) but we are very uncertain of both these findings. We found no long-term (longer than 12 months) data for any of the three primary outcomes.We found no evidence for any other comparisons and were unable to perform any of the preplanned subgroup analyses based on nerve-sparing approach, age or baseline erectile function.

AUTHORS' CONCLUSIONS

Based on mostly very-low and some low-quality evidence, penile rehabilitation strategies consisting of scheduled PDE5I use following radical prostatectomy may not promote self-reported potency and erectile function any more than on demand use.

MSC-derived exosomes ameliorate erectile dysfunction by alleviation of corpus cavernosum smooth muscle apoptosis in a rat model of cavernous nerve injury

Background

This study investigated the therapeutic effects of MSC-derived exosomes (MSC-Exos) on erectile function in a rat model of cavernous nerve injury (CNI).

Methods

MSCs were isolated from rat bone marrow and exosomes were isolated from the supernatants by ultracentrifugation. The tissue explant adherent method was used to isolate and culture corpus cavernosum smooth muscle cells (CCSMCs). MSCs and CCSMCs were identified by flow cytometry, in vitro differentiation or immunofluorescence staining. Thirty-two 10-week-old male Sprague Dawley (SD) rats were divided into four groups: a sham operation group and bilateral CNI groups that received intracavernosal (IC) injection of either PBS, MSCs or MSC-Exos. Four weeks after CNI and treatment, the erectile function of the rats was measured by electrically stimulating the cavernous nerve. The penile tissues were harvested for blinded histologic analysis and western blotting. H₂O₂ was used to induce apoptosis in the CCSMCs, and a flow cytometer was used to measure the cell viability of the CCSMCs treated with or without exosomes in vitro.

Results

Recovery of erectile function was observed in the MSC-Exos group. The MSC-Exos treatment significantly enhanced smooth muscle content and neuronal nitric oxide synthase in the corpus cavernosum. The ratio of smooth muscle to collagen in the corpus cavernosum was significantly improved in the MSC-Exos treatment group compared to the PBS vehicle group. WB confirmed these biological changes. Cell viability of the CCSMCs was increased in the MSC-Exos-treated groups, and caspase-3 expression was decreased after the MSC-Exos treatment in vivo and in vitro.

Conclusions

Exosomes isolated from MSCs culture supernatants by ultracentrifugation could ameliorate CNI-induced ED in rats by inhibiting apoptosis in CCSMCs, with similar potency to that observed in the MSCs-treated group. Therefore, this cell-free therapy has great potential for application in the treatment of CNI-induced ED for replacing cell therapy.

Graphical abstract

MSC-derived exosomes ameliorate erectile dysfunction in a rat model of cavernous nerve injury

Efficacy and safety of low-intensity shock wave therapy in penile rehabilitation post nerve-sparing radical cystoprostatectomy: a randomized controlled trial

AIM

To evaluate the role of low-intensity extra corporeal shock wave therapy (LI-ESWT) in penile rehabilitation (PR) post nerve-sparing radical cystoprostatectomy (NS-RCP).

MATERIALS AND METHODS

This study included 152 sexually active men with muscle invasive bladder cancer. After bilateral NS-RCP with orthotopic diversion by a single expert surgeon between June 2014 and July 2016, 128 patients were available categorized into three groups: LI-ESWT group (42 patients), phosphodiesterase type-5 inhibitors (PDE5i) group (43 patients), and control group (43 patients).

RESULTS

Mean age was 53.2 ± 6.5 years. Mean ± SD follow-up period was 21 ± 8 months. During first follow-up FU1, all patients of the three groups had insufficient erection for vaginal penetration; with decrease of preoperative IIEF-EF mean score from 27.9 to 6.9. Potency recovery rates at 9 months were 76.2%, 79.1%, and 60.5% in LI-ESWT, PDE5i, and control groups, respectively. There was statistically significant increase in IIEF-EF and EHS scores during all follow-up periods in all the study groups (p < 0.001). However, there was no significant difference between the three groups during all follow-up periods. Statistical evaluation showed no significant difference in continence and oncological outcomes during all follow-up points among the three groups (p = 0.55 and 0.07, respectively).

CONCLUSIONS

During last follow-up, 16% more patients in LI-ESWT group had recovery of potency as compared to the control group. Although the difference is not statistically significant, but of clinical importance. LI-ESWT is safe as oral PDE5i in penile rehabilitation post nerve-sparing radical cystoprostatectomy.

Efficacy and Safety of Tadalafil 5 mg Once Daily for the Treatment of Erectile Dysfunction After Robot-Assisted Laparoscopic Radical Prostatectomy: A 2-Year Follow-Up

BACKGROUND

Although nerve-sparing robot-assisted radical prostatectomy (NS-RALP) is performed, a large number of patients still experience erectile dysfunction (ED) after surgery.

AIM

To evaluate the efficacy and safety of tadalafil 5 mg once daily (OaD) in ED treatment over 2 years and investigate the cause of vascular ED after NS-RARP.

METHODS

We retrospectively evaluated 95 men who underwent NS-RARP and had a penile rehabilitation treatment with tadalafil 5 mg OaD. They were classified into 3 groups: tadalafil 5 mg OaD for 2 years (group I), tadalafil 5 mg OaD for 1 year (group II), and no tadalafil (group III). All patients in group I underwent penile color duplex ultrasound to evaluate the cause of vascular ED.

OUTCOMES

Patients were surveyed using the abridged 5-item International Index of Erectile Function (IIEF-5).

RESULTS

Statistically significant improvements were observed in group I for all IIEF-5 domain scores (P = .000). There was no statistically significant difference in recovery of erectile function (EF) the 2-year follow-up between groups I and II. Sub-analysis based on NS status showed no difference in recovery of EF. However, group I showed better trends in EF improvement. Those with venogenic ED had poor responses compared with those with arteriogenic ED or unremarkable findings with tadalafil 5-mg OaD treatment (14.2% vs 55.0% vs 53.3%). The overall side effects included hot flushing in 9.5%, headache in 7.1%, and dizziness in 2.3% of patients.

CLINICAL IMPLICATIONS

Long-term usage of tadalafil 5 mg OaD after RARP can be an effective option for penile rehabilitation.

STRENGTHS AND LIMITATIONS

The present study is a retrospective study with a relatively small sample.

CONCLUSIONS

Although the responses of patients with venogenic ED were limited compared with those with arteriogenic ED, tadalafil 5-mg OaD treatment was well tolerated and significantly improved EF up to 2 years after NS-RARP. Kim S, Sung GT. Efficacy and Safety of Tadalafil 5 mg Once Daily for the Treatment of Erectile Dysfunction After Robot-Assisted Laparoscopic Radical Prostatectomy: A 2-Year Follow-Up. Sex Med 2018;6:108-114.

Interventions to Address Sexual Problems in People With Cancer: American Society of Clinical Oncology Clinical Practice Guideline Adaptation of Cancer Care Ontario Guideline

Purpose

The adaptation of the Cancer Care Ontario (CCO) guideline Interventions to Address Sexual Problems in People With Cancer provides recommendations to manage sexual function adverse effects that occur as a result of cancer diagnosis and/or treatment.

Methods

ASCO staff reviewed the guideline for developmental rigor and updated the literature search. An ASCO Expert Panel ( Table A1 ) was assembled to review the guideline content and recommendations.

Results

The ASCO Expert Panel determined that the recommendations from the 2016 CCO guideline are clear, thorough, and based upon the most relevant scientific evidence. ASCO statements and modifications were added to adapt the CCO guideline for a broader audience.

Recommendations

It is recommended that there be a discussion with the patient, initiated by a member of the health care team, regarding sexual health and dysfunction resulting from cancer or its treatment. Psychosocial and/or psychosexual counseling should be offered to all patients with cancer, aiming to improve sexual response, body image, intimacy and relationship issues, and overall sexual functioning and satisfaction. Medical and treatable contributing factors should be identified and addressed first. In women with symptoms of vaginal and/or vulvar atrophy, lubricants in addition to vaginal moisturizers may be tried as a first option. Low-dose vaginal estrogen, lidocaine, and dehydroepiandrosterone may also be considered in some cases. In men, medication such as phosphodiesterase type 5 inhibitors may be beneficial, and surgery remains an option for those with symptoms or treatment complications refractory to medical management. Both women and men experiencing vasomotor symptoms should be offered interventions for symptomatic improvement, including behavioral options such as cognitive behavioral therapy, slow breathing and hypnosis, and medications such as venlafaxine and gabapentin.Additional information is available at: www.asco.org/survivorship-guidelines and www.asco.org/guidelineswiki .

Does penile rehabilitation have a role in the treatment of erectile dysfunction following radical prostatectomy?

In men undergoing radical treatment for prostate cancer, erectile function is one of the most important health-related quality-of-life outcomes influencing patient choice in treatment. Penile rehabilitation has emerged as a therapeutic measure to prevent erectile dysfunction and expedite return of erectile function after radical prostatectomy. Penile rehabilitation involves a program designed to increase the likelihood of return to baseline-level erectile function, as opposed to treatment, which implies the therapeutic treatment of symptoms, a key component of post–radical prostatectomy management. Several pathological theories form the basis for rehabilitation, and a plethora of treatments are currently in widespread use. However, whilst there is some evidence supporting the concept of penile rehabilitation from animal studies, randomised controlled trials are contradictory in outcomes. Similarly, urological guidelines are conflicted in terms of recommendations. Furthermore, it is clear that in spite of the lack of evidence for the role of penile rehabilitation, many urologists continue to employ some form of rehabilitation in their patients after radical prostatectomy. This is a significant burden to health resources in public-funded health economies, and no effective cost-benefit analysis has been undertaken to support this practice. Thus, further research is warranted to provide both scientific and clinical evidence for this contemporary practice and the development of preventative strategies in treating erectile dysfunction after radical prostatectomy.

Erectile function recovery in men treated with phosphodiesterase type 5 inhibitor administration after bilateral nerve-sparing radical prostatectomy: a systematic review of placebo-controlled randomized trials with trial sequential analysis

The impact of phosphodiesterase type 5 inhibitor (PDE5I) treatment modality (on-demand vs. daily), PDE5I half-life and time from surgery to PDE5I prescription on the achievement of drug-assisted erectile function (EF) recovery is uncertain. We systematically reviewed published randomized clinical trials (RCTs). We performed meta-analyses of data on 2317 men treated with PDE5Is after nerve-sparing radical prostatectomy (NSRP). A PubMed and SCOPUS search was performed for trials published from 1 January 1969 to 30 June 2016. PDE5Is are effective in achieving drug-assisted recovery of erectile function (EF). From a statistical standpoint, these studies were subjected to Trial Sequential Analysis to determine whether the pooled data were adequately powered to verify the study outcomes. On-demand treatment with PDE5Is was significantly better than daily treatment in recovering drug-assisted EF. This effect was maintained even when the drugs were stratified according with half-life. Although not based on head-to-head trials, Avanafil used on-demand was the most effective PDE5I in recovering drug-assisted EF. Whereas tadalafil was equally effective when used both on-demand and daily, vardenafil significantly improved drug-assisted EF recovery only when used on-demand. The start of PDE5I treatment six months or more after surgery compared to treatment started earlier did not negatively affect the rate of drug-assisted EF recovery or the possibility to have successful intercourse based on the Sexual Encounter Profile question-3 (SEP-3). Current trials do not support the hypothesis that PDE5I use recovers drug-unassisted EF, although chronic low-dose tadalafil administration may help to preserve erectile tissue integrity. Potential shortcomings in the trials design may partially explain these disappointing results and several questions concerning the recovery of drug-unassisted EF remain unanswered. Thus, there is a need for well-designed new RCTs requiring changes in the timing of PDE5I administration as well as in the dose and the treatment duration.

Interventions to address sexual problems in people with cancer

BACKGROUND

Sexual dysfunction in people with cancer is a significant problem. The present clinical practice guideline makes recommendations to improve sexual function in people with cancer.

METHODS

This guideline was undertaken by the Interventions to Address Sexual Problems in People with Cancer Expert Panel, a group organized by the Program in Evidence-Based Care (pebc). Consistent with the pebc standardized approach, a systematic search was conducted for existing guidelines, and the literature in medline and embase for the years 2003-2015 was systematically searched for both systematic reviews and primary literature. Evidence found for men and for women was evaluated separately, and no restrictions were placed on cancer type or study design. Content and methodology experts performed an internal review of the resulting draft recommendations, which was followed by an external review by targeted experts and intended users.

RESULTS

The search identified 4 existing guidelines, 13 systematic reviews, and 103 studies with relevance to the topic. The present guideline provides one overarching recommendation concerning the discussion of sexual health and dysfunction, which is aimed at all people with cancer. Eleven additional recommendations made separately for men and women deal with issues such as sexual response, body image, intimacy and relationships, overall sexual functioning and satisfaction, and vasomotor and genital symptoms.

CONCLUSIONS

To our knowledge this clinical practice guideline is the first to comprehensively evaluate interventions for the improvement of sexual problems in people with cancer. The guideline will be a valuable resource to support practitioners and clinics in addressing sexuality in cancer survivors.

[Sexual consequences after treatment of prostate cancer: Inquiry among members of the Association Nationale des Malades du Cancer de la Prostate]

INTRODUCTION

Complications of prostate cancer treatments are responsible of a lower quality of life. We evaluated the prevalence and the perceptions of sexual consequences of prostate cancer treatments.

MATERIALS AND METHODS

A retrospective self-administered questionnaire was sent to all the members of the Association Nationale des Malades du Cancer de la Prostate (ANAMACAP). All the answers were analyzed.

RESULTS

226 questionnaires were analyzed, the average age was 67.3 years old, the average follow-up was 58.1 months. 110 patients had surgery only, 29 had hormone therapy plus radiotherapy, 28 had radiation therapy only and 49 had combined treatments. After the treatment of the prostate cancer, an erectile dysfunction was reported by 75.2% of the patients; an orgasmic dysfunction by 69%; a climacturia by 21%; a reduced penile length by 70% of them and a less sensitive glans by 59%. They were responsible of a lower quality of life for 75% to 90% of the patients depending on the symptom. A PDE5-inhibitor treatment was effective for only 25.6% of them when taken daily and for 39% on demand.

CONCLUSION

Functional consequences of prostate cancer treatments are common, diverse and directly involved in the sexual life. It is necessary to improve therapeutical education and onco-sexology with the help of patients' associations, to build a new balance in the couples.

LEVEL OF EVIDENCE

3.

Efficacy and safety of short- and long-term, regular and on-demand regimens of phosphodiesterase type 5 inhibitors in treating erectile dysfunction after nerve-sparing radical prostatectomy: a systematic review and meta-analysis

Background

We performed a meta-analysis to evaluate the efficacy and safety of short-term (≤6 months) and long-term (>6 months), regular (OaD) and on-demand (PRN) regimens of phosphodiesterase type 5 inhibitors (PDE5-Is) in treating erectile dysfunction (ED) after nerve-sparing radical prostatectomy (NSRP).

Methods

We conducted a literature search in August 2016. Sources included PubMed, EMBASE, and MEDLINE databases. The main outcome was International Index of Erectile Function-Erectile Function (IIEF-EF) domain score, and the secondary outcome was treatment-emergent adverse events (TEAEs).

Results

Eight articles involving 13 randomized controlled trials (RCTs) were used in this analysis: they suggested that PDE5-Is can improve the IIEF-EF distinctly in comparison with placebo in short and long term (mean difference [MD]: 2.26, 95% confidence interval [CI]: 1.45–3.08, P<0.00001, and MD: 4.5, 95% CI: 3.6–5.4, P<0.00001), and long-term use of PDE5-Is (>6 months) can improve the IIEF-EF distinctly in comparison with short-term use of PDE5-Is (≤6 months) (MD: 3.9, 95% CI: 3.01–4.8, P<0.00001). OaD of PDE5-Is significantly improved the IIEF-EF compared to placebo in short and long term (MD: 4.08, 95% CI: 3.2–4.97, P<0.00001, and MD: 4.74, 95% CI: 3.79–5.69, P<0.00001). No significant differences were found in IIEF-EF changes between PRN and placebo (≤6 months) (MD: 2.64, 95% CI: −0.87 to 6.14, P=0.14), and between PRN and OaD group (>6 months) (MD: −0.58, 95% CI: −9.86 to 8.74, P=0.91). There were more TEAEs in PDE5-Is group in comparison with placebo (odds ratio [OR]: 1.55, 95% CI: 1.26–1.91, P<0.0001), and TEAEs in OaD group were not significantly different from those seen in PRN group (OR: 1.05, 95% CI: 0.78–1.4, P=0.77).

Conclusion

Our meta-analysis suggests that PDE5-Is are efficient and safe for treatment of ED after NSRP, and we should choose the regular regimen for short term and regular or on-demand regimen for long term. Further high-quality RCTs are needed to validate this result.

The controversy surrounding penile rehabilitation after radical prostatectomy

Radical prostatectomy (RP) techniques have been refined in the last few decades. Despite nerve-sparing surgery, erectile dysfunction (ED) still seems to be affecting more than half of patients undergoing RP. Penile rehabilitation consists of understanding the mechanisms that affect erectile function (EF) and utilizing pharmacologic agents, devices or interventions to promote male sexual function before and after any insult to the penile erectile physiologic axis. There currently is a limited amount of clinical trials that assess treatments with the goal of recovering post-prostatectomy EF. The goal of this article is to assess a contemporary series of trials that study penile rehabilitation. Although the current evidence lacks to prove its irrefutable effectiveness, advancements in research and technology forecast a promising future in penile rehabilitation management.

Comparisons of regular and on-demand regimen of PED5-Is in the treatment of ED after nerve-sparing radical prostatectomy for Prostate Cancer

Phosphodiesterase type-5 inhibitors (PDE5-Is) have been recommended as first line therapy for erectile dysfunction for patients received nerve-sparing radical prostatectomy for prostate cancer. We examed the efficiency of PDE5-Is and considered the optimal application. Systematic search of PubMed, Embase and the Cochrane Library was performed to identify all the studies. We identified 103 studies including 3175 patients, of which 14 were recruited for systematic review. Compared with placebo, PDE5-Is significantly ameliorated the International Index of Erectile Function-Erectile Function domain score (IIEF) scores (MD 4.89, 95% CI 4.25-5.53, p < 0.001). By network meta-analysis, sildenafil seems to be the most efficiency with a slightly higher rate of treatment-emergent adverse events (TEATs), whereas tadalafil had the lowest TEATs. In terms of IIEF scores, regular regimen was remarkably better than on-demand (MD 3.28, 95% CI 1.67-4.89, p < 0.001). Regular use was not associated with higher proportion of patients suffering TEATs compared with on-demand (RR 1.02, 95% CI 0.90-1.16, p = 0.72). Compared with placebo, PDE5-Is manifested significantly improved treatment outcomes. Overall, regular regimen demonstrated statistically pronounced better potency than on-demand. Coupled with the comparable rate of side effects, these findings support the regular delivery procedure to be a cost-effective option for patients.

Phosphodiesterase-5 Inhibitors and Vacuum Erection Device for Penile Rehabilitation After Laparoscopic Nerve-Preserving Radical Proctectomy for Rectal Cancer: A Prospective Controlled Trial

The current study sought to clarify the role of phosphodiesterase type 5 inhibitors (PDE-5i) and a vacuum erection device (VED) in penile rehabilitation after laparoscopic nerve-preserving radical proctectomy (LNRP) for rectal cancer. Participants were assigned to one of the following arms-no-intervention, nightly use of sildenafil 25 mg for 3 months after surgery, or concurrent use of nightly sildenafil 25 mg/day for 3 months and a vacuum erection device (VED) 10 to 15 minutes/day for 3 months-in a nonrandomized fashion. All participants had a follow-up of over 12 months prospectively, and patients had baseline, 3-, 6-, and 12-month assessment based on the International Index of Erectile Function-5 (IIEF-5). Seventy-one cases were included in final analyses. In the no-intervention group, the mean baseline IIEF-5 score of 21.9 decreased rapidly to 5.0 at 3 months ( p < .001), 9.2 at 6 months ( p < .001), and stayed at 10.9 at 12 months ( p < .001). In the single therapy group, the mean baseline IIEF-5 score of 22.4 decreased dramatically to 9.0 at 3 months ( p < .001), 14.9 at 6 months ( p = .005), and stayed at 15.1 at 12 months ( p = .005). In the combined therapy group, the mean baseline IIEF-5 score of 23.0 decreased slightly to 15.0 at 3 months ( p = .005), 18.0 at 6 months ( p = .038), and maintained at 18.7 at 12 months ( p = .163). Findings suggested an over 50% decline in the quality of erection function of the patients after LNRP. The early use of PDE-5i alone or combined use of PDE-5i and VED after LNRP maintained erectile function at 12 months.

Postprostatectomy Erectile Dysfunction: A Review

In the current era of the early diagnosis of prostate cancer (PCa) and the development of minimally invasive surgical techniques, erectile dysfunction (ED) represents an important issue, with up to 68% of patients who undergo radical prostatectomy (RP) complaining of postoperative erectile function (EF) impairment. In this context, it is crucial to comprehensively consider all factors possibly associated with the prevention of post-RP ED throughout the entire clinical management of PCa patients. A careful assessment of both oncological and functional baseline characteristics should be carried out for each patient preoperatively. Baseline EF, together with age and the overall burden of comorbidities, has been strongly associated with the chance of post-RP EF recovery. With this goal in mind, internationally validated psychometric instruments are preferable for ensuring proper baseline EF evaluations, and questionnaires should be administered at the proper time before surgery. Careful preoperative counselling is also required, both to respect the patient's wishes and to avoid false expectations regarding eventual recovery of baseline EF. The advent of robotic surgery has led to improvements in the knowledge of prostate surgical anatomy, as reflected by the formal redefinition of nerve-sparing techniques. Overall, comparative studies have shown significantly better EF outcomes for robotic RP than for open techniques, although data from prospective trials have not always been consistent. Preclinical data and several prospective randomized trials have demonstrated the value of treating patients with oral phosphodiesterase 5 inhibitors (PDE5is) after surgery, with the concomitant potential benefit of early re-oxygenation of the erectile tissue, which appears to be crucial for avoiding the eventual penile structural changes that are associated with postoperative neuropraxia and ultimately result in severe ED. For patients who do not properly respond to PDE5is, proper counselling regarding intracavernous treatment should be considered, along with the further possibility of surgical treatment for ED involving the implantation of a penile prosthesis.

Penile rehabilitation following prostate cancer treatment: review of current literature

Radical prostatectomy (RP) and radiotherapy (RT) are highly effective in improving prostate cancer survival. However, both have a detrimental effect on erectile function (EF). Penile rehabilitation consists of understanding the mechanisms that cause erectile dysfunction (ED) and utilizing pharmacologic agents, devices or interventions to promote male sexual function. For the past decade, many researchers have pursued to define effective treatment modalities to improve ED after prostate cancer treatment. Despite the understanding of the mechanisms and well-established rationale for postprostate treatment penile rehabilitation, there is still no consensus regarding effective rehabilitation programs. This article reviews a contemporary series of trials that assess penile rehabilitation and explore treatment modalities that might play a role in the future. Published data and trials related to penile rehabilitation after RP and RT were reviewed and presented. Although recent trials have shown that most therapies are well-tolerated and aid in some degree on EF recovery, we currently do not have tangible evidence to recommend an irrefutable penile rehabilitation algorithm. However, advancements in research and technology will ultimately create and refine management options for penile rehabilitation.

Useful Implications of Low-dose Long-term Use of PDE-5 Inhibitors

INTRODUCTION

Phosphodiesterase type 5 (PDE-5) hydrolyzes cyclic guanylate monophosphate (cGMP) specifically to 5' GMP, promoting successful corporeal vascular relaxation and penile erection during sexual stimulation. Oral PDE-5 inhibitors such as sildenafil, vardenafil, tadalafil, and avanafil have provided noninvasive, effective, well-tolerated treatment for erectile dysfunction (ED) patients and, at the same time, stimulated both academic and clinical interests. Lately, some oral PDE-5 inhibitors were released as low-dose preparations with the concept of potential daily administration and long-term use.

AIM

To highlight the possible potential implications of low-dose long-term use of PDE-5 inhibitors.

METHOD

A systematic review was carried out until December 2015 based on a search of all concerned articles in MEDLINE, medical subjects heading (MeSH) databases, Scopus, The Cochrane Library, EMBASE, and CINAHL databases without language restriction. Key words used to assess the outcome and estimates for concerned associations were: PDE-5 inhibitors; erectile dysfunction; low-dose; long-term; sildenafil; tadalafil; vardenafil; avanafil.

MAIN OUTCOME MEASURES

Demonstrating different implications for low-dose long-term use of PDE-5 inhibitors.

RESULTS

Low-dose and/or long-term use of PDE-5 inhibitors was shown to put forth beneficial sound effects in different medical implications with potentials that could be extended for different utilities. These implications included sexual, urogenital, cardiovascular, pulmonary, cutaneous, gastrointestinal, and reproductive, as well as neurological disorders. However, it is evident that most potential appliances were carried out experimentally on preclinical studies with off-label indications.

CONCLUSION

Making use of and exploring low-dose and/or long-term use of several PDE-5 inhibitors for their possible implications seem to be valuable in different medical disorders. Increased knowledge of the drug characteristics, comparative treatment regimens, optimal prescribing patterns, and well-designed clinical trials are needed before these agents can be recommended for use.

Prevention and management of post prostatectomy erectile dysfunction

Sexual dysfunction is common in patients with prostate cancer (PC) following radical prostatectomy (RP). Review the available literature concerning prevention and management strategies for post-RP erectile function (EF) impairment in terms of preoperative patient characteristics, intra and postoperative factors that may influence EF recovery, and postoperative treatments for erectile dysfunction (ED). A literature search was performed using Google and PubMed database for English-language original and review articles, either published or e-published up to July 2013. The literature still demonstrates a great inconsistency in the definition of what is considered normal EF both before and after RP. Thus, using validated psychometric instruments with recognized cut-offs for normalcy and severity during the pre- and post-operative evaluation should be routinely considered. Therefore, a comprehensive discussion with the patient about the true prevalence of postoperative ED, the concept of spontaneous or pharmacologically-assisted erections, and the difference between “back to baseline” EF and “erections adequate enough to have successful intercourse” clearly emerge as key issues in the eventual understanding of post-RP ED prevention and promotion of satisfactory EF recovery. Patient factors (including age, baseline EF, comorbid conditions status), cancer selection (non- vs. uni- vs. bilateral nerve-sparing), type of surgery (i.e., intra vs. inter vs. extrafascial surgeries), surgical techniques (i.e., open, laparoscopic and robotically-assisted RP), and surgeon factors (i.e., surgical volume and surgical skill) represent the key significant contributors to EF recovery. A number of preclinical and clinical data show that rehabilitation and treatment in due time are undoubtedly better than leaving the erectile tissue to its unassisted postoperative fate. The role of postoperative ED treatment for those patients who received a non-nerve-sparing RP was also extensively discussed. Optimal outcomes are achieved mainly by the careful choice of the correct patient for the correct type of surgery. Despite a plethora of potential rehabilitative approaches, they should be only considered as “strategies”, since incontrovertible evidence of their effectiveness for improving natural EF recovery is limited. Conversely, numerous effective therapeutic options are available for treating post-RP ED.

Pharmacologic and surgical therapies for sexual dysfunction in male cancer survivors

The recent recognition that many men experience sexual dysfunction following their diagnosis and treatment of genitourinary cancers, has led to the development multiple varied strategies that attempt to restore or preserve that function. In this manuscript we review the understanding of why it happens, highlight novel management strategies and discuss the concept of penile rehabilitation (PR) following prostate cancer (PCa) treatment, glans preserving strategies among men diagnosed with penile cancer and address the controversial issue of testosterone therapy in men with PCa.

Nightly sildenafil use after radical prostatectomy has adverse effects on urinary convalescence: Results from a randomized trial of nightly vs on-demand dosing regimens

INTRODUCTION

This is a report on urinary function results from a randomized trial of nightly versus on-demand sildenafil after nerve-sparing radical prostatectomy (RP), a secondary objective. We analyzed the effects of these sildenafil administration schemes on urinary health-related quality of life after RP.

METHODS

In total, 100 potent men were equally randomized to nightly and on-demand sildenafil 50 mg after minimally-invasive RP for 1 year. Health-related quality of life questionnaires were administered at various postoperative intervals. Urinary function was assessed using appropriate expanded prostate cancer index composite (EPIC) subscales. Analyses of covariance and linear mixed-effects modeling were used to compare the effects of treatment over time on urinary recovery, controlling for age, nerve-sparing score, and time from surgery.

RESULTS

The nightly (n = 50) and on-demand (n = 50) sildenafil groups were well-matched at baseline. Nightly sildenafil patients had worse EPIC urinary bother and urinary irritative/obstructive subscale scores at 3 and 6 months after RP, even after controlling for multiple variables. On mixed-model analyses, the differences between groups for these EPIC subscales (4.9 and 2.5, respectively) were greater than documented thresholds for clinical significance. Increasing nerve-sparing score was associated with improvements in EPIC urinary summary, bother, incontinence, and function scores; time from surgery was associated with improvements in all EPIC urinary health-related quality of life subscales.

CONCLUSIONS

In this specific population and drug dose, we found that on-demand short-acting phosphodiesterase-5 inhibitor (PDE5i) dosing may be more effective after RP to maximize early urinary health-related quality of life. In preoperatively potent men, nightly sildenafil 50 mg impaired urinary health-related quality of life more than on-demand use in the early months after nerve-sparing RP, independent of effects on urinary continence.

Pelvic floor muscle training for erectile dysfunction and climacturia 1 year after nerve sparing radical prostatectomy: a randomized controlled trial

This study aimed to determine whether patients with persistent erectile dysfunction (ED), minimum 12 months after radical prostatectomy (RP), experienced a better recovery of erectile function (EF) with pelvic floor muscle training (PFMT) compared with patients without this intervention. Second, we aimed to investigate the effect of PFMT on climacturia. All patients, who underwent RP, with persistent ED of minimum 1 year post operation were eligible. The treatment group started PFMT immediately at 12 months post operation and the control group started at 15 months after RP. All patients received PFMT during 3 months. The sample size needed to detect with 80% power a 6 points-difference regarding the EF-domain of the International Index of Erectile Function (IIEF), was at least 12 subjects per group. Patients were evaluated using the IIEF and questioned regarding climacturia. Differences between groups at 15 months were evaluated with Mann-Whitney U-test and Fisher's exact test. As a result, the treatment group had a significantly better EF than the control group at 15 months after surgery (P=0.025). Other subdomains of the IIEF remained constant for both groups. The effect of PFMT was maintained during follow-up. At 15 months, a significantly higher percentage of patients in the treatment group showed an improvement regarding climacturia (P=0.004).