Comprehensive analysis of sexual function outcome in prostate cancer patients after robot-assisted radical prostatectomy

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.

Predicting trajectories of recovery in prostate cancer patients undergone Robot-Assisted Radical Prostatectomy (RARP)

OBJECTIVE

To identify trends of patients' urinary and sexual dysfunctions from a clinical and psychological perspective and understand whether sociodemographic and medical predictors could differentiate among patients following different one-year longitudinal trajectories.

METHODS

An Italian sample of 478 prostate cancer patients undergone Robot-Assisted Radical Prostatectomy completed the EPIC-26 survey between July 2015 and July 2016 at the pre-hospitalization (T0), 45 days (T1) and 3 (T2), 6 (T3), 9 (T4), and 12 months (T5) after surgery. Sociodemographic and clinical characteristics (age, BMI, diabetes, nerve-sparing procedure) were also collected. Latent Class Growth Analysis was conducted separately for sexual dysfunction and urinary incontinence EPIC-26 subscales. The association between membership in the two longitudinal trajectories of urinary and sexual dysfunctions was assessed by considering Chi-square test and its related contingency table.

RESULTS

People who have a high level of urinary incontinence at T1 are likely to have a worse recovery. Age, BMI and pre-surgical continence may affect the level of incontinence at T1 and the recovery trajectories. Patients with low and moderate sexual problems at T1 can face a moderate linear recovery, while people with high level of impotence immediately after surgery may take a longer period to solve sexual dysfunctions. Age and the pre-surgical sexual condition may impact the recovery. Finally, a great proportion of patients reported both steady problems in sexual function and constant high levels of urinary incontinence over time.

CONCLUSIONS

This study highlights different categories of patients at risk who may be important to know in order to develop personalized medical pathways and predictive models in a value-based healthcare.

Association Between Radiation Therapy, Surgery, or Observation for Localized Prostate Cancer and Patient-Reported Outcomes After 3 Years

Importance

Understanding the adverse effects of contemporary approaches to localized prostate cancer treatment could inform shared decision making.

Objective

To compare functional outcomes and adverse effects associated with radical prostatectomy, external beam radiation therapy (EBRT), and active surveillance.

Design, Setting, and Participants

Prospective, population-based, cohort study involving 2550 men (≤80 years) diagnosed in 2011-2012 with clinical stage cT1-2, localized prostate cancer, with prostate-specific antigen levels less than 50 ng/mL, and enrolled within 6 months of diagnosis.

Exposures

Treatment with radical prostatectomy, EBRT, or active surveillance was ascertained within 1 year of diagnosis.

Main Outcomes and Measures

Patient-reported function on the 26-item Expanded Prostate Cancer Index Composite (EPIC) 36 months after enrollment. Higher domain scores (range, 0-100) indicate better function. Minimum clinically important difference was defined as 10 to 12 points for sexual function, 6 for urinary incontinence, 5 for urinary irritative symptoms, 5 for bowel function, and 4 for hormonal function.

Results

The cohort included 2550 men (mean age, 63.8 years; 74% white, 55% had intermediate- or high-risk disease), of whom 1523 (59.7%) underwent radical prostatectomy, 598 (23.5%) EBRT, and 429 (16.8%) active surveillance. Men in the EBRT group were older (mean age, 68.1 years vs 61.5 years, P < .001) and had worse baseline sexual function (mean score, 52.3 vs 65.2, P < .001) than men in the radical prostatectomy group. At 3 years, the adjusted mean sexual domain score for radical prostatectomy decreased more than for EBRT (mean difference, -11.9 points; 95% CI, -15.1 to -8.7). The decline in sexual domain scores between EBRT and active surveillance was not clinically significant (-4.3 points; 95% CI, -9.2 to 0.7). Radical prostatectomy was associated with worse urinary incontinence than EBRT (-18.0 points; 95% CI, -20.5 to -15.4) and active surveillance (-12.7 points; 95% CI, -16.0 to -9.3) but was associated with better urinary irritative symptoms than active surveillance (5.2 points; 95% CI, 3.2 to 7.2). No clinically significant differences for bowel or hormone function were noted beyond 12 months. No differences in health-related quality of life or disease-specific survival (3 deaths) were noted (99.7%-100%).

Conclusions and Relevance

In this cohort of men with localized prostate cancer, radical prostatectomy was associated with a greater decrease in sexual function and urinary incontinence than either EBRT or active surveillance after 3 years and was associated with fewer urinary irritative symptoms than active surveillance; however, no meaningful differences existed in either bowel or hormonal function beyond 12 months or in in other domains of health-related quality-of-life measures. These findings may facilitate counseling regarding the comparative harms of contemporary treatments for prostate cancer.

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.

Off-Target Effect of Sildenafil on Postsurgical Erectile Dysfunction: Alternate Pathways and Localized Delivery System

INTRODUCTION

There is no consensus on the best oral phosphodiesterase type 5 inhibitor (PDE5I) for patients undergoing penile rehabilitation after surgical nerve injury.

AIM

To determine the mechanism of PDE5I on cultured neuronal cells and the effectiveness of local drug delivery using nanospheres (NSPs) to sites of nerve injury in a rat model of bilateral cavernous nerve injury (BCNI).

METHODS

The effects of sildenafil, tadalafil, and vardenafil on cyclic adenosine monophosphate, cyclic guanosine monophosphate, and cell survival after exposure to hypoxia and H₂O₂ were measured in PC12, SH-SY5Y, and NTERA-2 (NT2) cell cultures. The effects of phosphodiesterase type 4 inhibitor (PDE4I) and PDE5I on neuronal cell survival were evaluated. Male rats underwent BCNI and were untreated (BCNI), immediately treated with application of empty NSPs (BCNI + NSP), NSPs containing sildenafil (Sild + NSP), or NSPs containing rolipram (Rol + NSP).

MAIN OUTCOME MEASURES

Viability of neuronal cells was measured. Intracavernous pressure changes after cavernous nerve electrostimulation and expression of neurofilament, nitric oxide synthase, and actin in mid-shaft of penis were analyzed 14 days after injury.

RESULTS

Sildenafil and rolipram significantly decreased cell death after exposure to H₂O₂ and hypoxia in PC12, SH-SY5Y, and NT2 cells. PC12 cells did not express PDE5 and knockdown of PDE4 significantly increased cell viability in PC12, SH-SY5Y, and NT2 cells exposed to hypoxia. The ratio of intracavernous pressure to mean arterial pressure and expression of penile neurofilament, nitric oxide synthase, and actin were significantly higher in the Sild + NSP and Rol + NSP groups than in the BCNI and BCNI + NSP groups. Limitations included analysis in only two PDE families using only a single dose.

CONCLUSION

Sildenafil showed the most profound neuroprotective effect compared with tadalafil and vardenafil. Sildenafil- or rolipram-loaded NSP delivery to the site of nerve injury prevented erectile dysfunction and led to increased neurofilament, nitric oxide synthase, smooth muscle content in rat penile tissue after BCNI.

Clinicopathological, functional, and immediate oncologic outcome assessment in men aged≤50 years with prostate cancer after robotic prostatectomy

BACKGROUND

To define the pathologic and functional outcomes of men 50 years of age and younger with prostate cancer in a contemporary robotic cohort, this study was designed.

METHODS

Patients undergoing robotic-assisted laparoscopic prostatectomy from April 2002 to April 2012 (n = 2,495) formed the base population for the current analyses. The patients were dichotomized according to their age≤50 (n = 271) and>50-year-old (n = 2,224). Clinicopathological and health-related quality-of-life outcomes were recorded and analyzed for differences. Propensity score matching was used when assessing urinary and sexual function outcome.

RESULTS

Baseline prostate-specific antigen and clinical stage were similar between men older than 50 years and those younger. Younger patients had less severe disease (D׳Amico risk and Gleason scores) and smaller prostates. Young men had higher rates of erectile function at all time points, including baseline (94% vs. 83% at 12mo, P <0.01). Continence was similar at all time points except for 6 months, where younger patients experienced a faster return than older patients and then remained constant, while older patients continued to improve (96% vs. 89%, P<0.01). After matching process, the difference in erectile function at 6-month follow-up was lost.

CONCLUSION

Most men aged 50 years and younger who received robotic-assisted laparoscopic prostatectomy had clinically significant prostate cancer. Although histopathologic and short-term oncologic outcomes were nearly identical when compared to older patients, younger men had a more rapid and superior return of erectile function.

Uroflow Stop Test and Potency Recovery: A Surrogate for Pelvic Floor Integrity Post Robotic-Assisted Radical Prostatectomy?

OBJECTIVE

To study the relation between uroflow Stop Test and early recovery of potency following robot-assisted radical prostatectomy (RARP). We recently showed that the ability to completely stop urine flow during voiding, measured objectively by uroflowmetry at the time of catheter removal (uroflow Stop Test) can predict early urinary continence recovery following RARP.

MATERIALS AND METHODS

In this prospective observational cohort, data were collected on 108 patients operated by a single surgeon (AEH). Eighty patients had a positive uroflow Stop Test (group one) and 28 had a negative Stop Test (group two). Patients were followed for a minimum of 2 years. Covariates included age, body mass index, international prostate symptom score and sexual health inventory for men scores, prostate-specific antigen, tumor stage, prostate volume, nerve sparing status, and estimated blood loss.

RESULTS

Preoperative characteristics were comparable between both groups except nerve sparing and prostate-specific antigen which were statistically higher in group one (P <.05). Early 3- and 6-months recovery of erectile function was significantly higher in group one. Potency rates in group one and two at 1, 3, 6, 9, 12, 18, and 24 months were 25% vs 14.3% (P = .241), 54.5% vs 18.5% (P = .001), 55.4% vs 18.5% (P = .001), 56.4% vs 36% (P = .084), 66.6% vs 50% (P = .141), 65.5% vs 56% (P = .404) and 73.2% vs 57.7% (P = .160) respectively. Uroflow Stop Test was independent predictor of early potency recovery on multivariate regression analysis at 6 months [odds ratio 6.042 (confidence interval 95% 1.496-24.413) P = .012].

CONCLUSION

Uroflow Stop Test is simple and can help predict early potency recovery following RARP.

Flexibility in Men's Sexual Practices in Response to Iatrogenic Erectile Dysfunction after Prostate Cancer Treatment

INTRODUCTION

Prostate cancer (PCa) treatments are associated with a high incidence of erectile dysfunction (ED). Interventions to help men with iatrogenic ED have largely focused on penile tumescence adequate for vaginal penetration. Less research has been undertaken on sex practices other than penile/vaginal intercourse.

AIM

The aim of this study was to explore forms of sexual practice engaged in by men following treatment for PCa. We focused in particular on anal intercourse (AI) as practiced by both nonheterosexual (i.e., gay-identified men and other men who have sex with men) and heterosexual men. We sought to determine how common AI was subsequent to PCa treatment and how flexible AI practitioners were in their modes (e.g., from insertive to receptive) when faced with iatrogenic ED.

METHODS

An international online survey was conducted in 2010-2011 of men treated for PCa, where participants (N = 558) were asked explicitly about their sexual practices before and after PCa treatment.

MAIN OUTCOME MEASURES

The outcome measures were the numbers and percentages of men who practiced AI before and after PCa treatment as well as the percentage who changed AI practice after PCa treatment.

RESULTS

Five hundred twenty-six men (90 nonheterosexual men; 436 heterosexual men) answered questions on AI practices. A proportion of nonheterosexual (47%) and heterosexual men (7%) practiced AI following PCa treatment, and did so in all modes (insertive, receptive, and "versatile"). Many nonheterosexual men continued to be sexually active in the face of iatrogenic ED by shifting from the insertive to receptive modes. A few men, both heterosexual and nonheterosexual, adopted AI for the first time post-PCa treatment.

CONCLUSIONS

Flexibility in sexual practice is possible for some men, both nonheterosexual and heterosexual, in the face of iatrogenic ED. Advising PCa patients of the possibilities of sexual strategies that include AI may help them in reestablishing a sex life that is not erection dependent. Dowsett GW, Lyons A, Duncan D, and Wassersug RJ. Flexibility in men's sexual practices in response to iatrogenic erectile dysfunction after prostate cancer treatment. Sex Med 2014;2:115-120.