Current state of penile rehabilitation after radical prostatectomy

Landmarks in erectile function recovery after radical prostatectomy

The description of the nerve-sparing technique of radical prostatectomy by Walsh was one of the major breakthroughs in the surgical treatment of prostate cancer in the 20(th) century. However, despite this advance and consequent technological refinements to nerve-sparing surgery, a large proportion of men still suffer from erectile dysfunction (ED) as a complication of prostatectomy. A plethora of therapeutic approaches have been proposed to optimize erectile function recovery in these patients. Several preclinical and translational studies have shown benefits of therapies including PDE5 inhibitor (PDE5I) treatment, immunomodulation, neurotrophic factor administration, and regenerative techniques, such as stem cell therapy, in animal models. However, most of these approaches have either failed to translate to clinical use or have yet to be studied in human subjects. Penile rehabilitation with PDE5Is is currently the most commonly used clinical strategy, in spite of the absence of solid clinical evidence to support its use.

American Cancer Society prostate cancer survivorship care guidelines

Prostate cancer survivors approach 2.8 million in number and represent 1 in 5 of all cancer survivors in the United States. While guidelines exist for timely treatment and surveillance for recurrent disease, there is limited availability of guidelines that facilitate the provision of posttreatment clinical follow-up care to address the myriad of long-term and late effects that survivors may face. Based on recommendations set forth by a National Cancer Survivorship Resource Center expert panel, the American Cancer Society developed clinical follow-up care guidelines to facilitate the provision of posttreatment care by primary care clinicians. These guidelines were developed using a combined approach of evidence synthesis and expert consensus. Existing guidelines for health promotion, surveillance, and screening for second primary cancers were referenced when available. To promote comprehensive follow-up care and optimal health and quality of life for the posttreatment survivor, the guidelines address health promotion, surveillance for prostate cancer recurrence, screening for second primary cancers, long-term and late effects assessment and management, psychosocial issues, and care coordination among the oncology team, primary care clinicians, and nononcology specialists. A key challenge to the development of these guidelines was the limited availability of published evidence for management of prostate cancer survivors after treatment. Much of the evidence relies on studies with small sample sizes and retrospective analyses of facility-specific and population databases.

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

OBJECTIVES

To clarify the role of phosphodiesterase type 5 (PDE5) inhibitors in post-prostatectomy penile rehabilitation (PPPR). To compare nightly and on-demand use of PDE5 inhibitors after nerve-sparing minimally invasive radical prostatectomy (RP).

PATIENTS AND METHODS

We conducted a single-institution, double-blind, randomized controlled trial of nightly vs on-demand 50-mg sildenafil citrate after nerve-sparing minimally invasive RP. A total of 100 preoperatively potent men, aged <65 years, with scores on the Erectile Function domain of the International Index of Erectile Function (IIEF-EF) ≥26, underwent nerve-sparing surgery. The patients were randomized to either nightly sildenafil and on-demand placebo (nightly sildenafil group), or on-demand sildenafil and nightly placebo (on-demand sildenafil group; maximum on-demand dose six tablets/month) for 12 months. Patients then underwent a 1-month washout period. Validated measures of erectile function (IIEF-EF score and the Expanded Prostate Cancer Index Composite [EPIC]) were compared between treatment groups over the entire 13-month time course, using multivariable mixed linear regression models.

RESULTS

The treatment groups were well matched preoperatively (mean age 54.3 vs 54.6 years, baseline IIEF-EF score 29.4 vs 29.3, for the nightly vs the on-demand sildenafil groups, respectively). No significant differences were found in erectile function between treatments (nightly vs on-demand sildenafil) at any single timepoint after RP, after adjusting for potential confounding factors. When evaluated over all timepoints simultaneously, no significant effects of treatment group (nightly vs on-demand sildenafil) were found on recovery of potency, as assessed by absolute IIEF-EF scores (P = 0.765), on percentage of men returning to an IIEF-EF score >21 (P = 0.830), or on IIEF-EF score recovery to a percentage of baseline value (P = 0.778). When evaluated over all timepoints simultaneously, no significant effects of treatment group were found on secondary endpoints such as assessment of potency (including EPIC item 59 response 'erections firm enough for intercourse'), attempted intercourse frequency or confidence.

CONCLUSIONS

Erectile recovery up to 1 year after RP does not differ between previously potent men who use sildenafil nightly compared to on-demand. This trial does not support chronic nightly sildenafil as being any better than on-demand sildenafil for use in penile rehabilitation after nerve-sparing minimally invasive RP.

Erectile dysfunction after radical prostatectomy: treatment options

Erectile dysfunction is a common problem after radical prostatectomy, with almost all men experiencing this complication for at least a short period after such surgery. There is evidence that early use of phosphodiesterase type 5 inhibitors, intracavernous vasoactive drugs, intraurethral alprostadil or vacuum devices can improve the recovery of postoperative erectile function. The same therapeutic modalities can be used to treat erectile dysfunction after radical prostatectomy. Physicians must be active and counsel patients and partners to improve adherence to penile rehabilitation or erectile dysfunction treatment.

Sildenafil promotes smooth muscle preservation and ameliorates fibrosis through modulation of extracellular matrix and tissue growth factor gene expression after bilateral cavernosal nerve resection in the rat

INTRODUCTION

It has been shown that phosphodiesterase type 5 (PDE5) inhibitors preserve smooth muscle (SM) content and ameliorate the fibrotic degeneration normally seen in the corpora cavernosa after bilateral cavernosal nerve resection (BCNR). However, the downstream mechanisms by which these drugs protect the corpora cavernosa remain poorly understood.

AIM

To provide insight into the mechanism, we aimed to determine the gene expression profile of angiogenesis-related pathways within the penile tissue after BCNR with or without continuous sildenafil (SIL) treatment.

METHODS

Five-month-old Fisher rats were subjected to BCNR or sham operation and treated with or without SIL (20 mg/kg/BW drinking water) for 3 days or 45 days (N = 8 rats per group). Total RNAs isolated from the denuded penile shaft and prostate were subjected to reverse transcription and to angiogenesis real-time-polymerase chain reaction arrays (84 genes). Changes in protein expression of selected genes such as epiregulin (EREG) and connective tissue growth factor (CTGF) were corroborated by Western blot and immunohistochemistry.

MAIN OUTCOMES MEASURES

Genes modulated by BCNR and SIL treatment.

RESULTS

A decreased expression of genes related to SM growth factors such as EREG, platelet-derived growth factor (PDGF), extracellular matrix regulators such as metalloproteinases 3 and 9, endothelial growth factors, together with an upregulation of pro-fibrotic genes such as CTGF and transforming growth factor beta 2 were found at both time points after BCNR. SIL treatment reversed this process by upregulating endothelial and SM growth factors and downregulating pro-fibrotic factors. SIL did not affect the expression of EREG, VEGF, and PDGF in the ventral prostate of BCNR animals.

CONCLUSIONS

SIL treatment after BCNR activates genes related to SM preservation and downregulates genes related to fibrosis in the corpora cavernosa. These results provide a mechanistic justification for the use of SIL and other PDE5 inhibitors as protective therapy against corporal SM loss and fibrosis after radical prostatectomy.