Cavernous nerve reconstruction to preserve erectile function following non-nerve-sparing radical retropubic prostatectomy: a prospective study

Interpositional Nerve Grafting of the Prostatic Plexus after Radical Prostatectomy

Background:

Injury to the prostatic plexus may occur during radical prostatectomy even with the use of minimally invasive techniques. Reconstruction of these nerves by interpositional nerve grafting can be performed to reduce morbidity. Although the feasibility of nerve reconstruction has been shown, long-term functional outcomes are mixed, and the role of nerve grafting in these patients remains unclear.

Methods:

A retrospective study was performed on 38 consecutive patients who underwent immediate unilateral or bilateral nerve reconstruction after open prostatectomy. Additionally, 53 control patients who underwent unilateral, bilateral, or non–nerve-sparing open prostatectomy without nerve grafting were reviewed. Outcomes included rates of urinary continence, erections sufficient for sexual intercourse, and ability to have spontaneous erections. Analysis was performed by stratifying patients by D’Amico score and laterality of nerve involvement.

Results:

Unilateral nerve grafting conferred no significant benefit compared with unilateral nerve-sparing prostatectomy. Bilateral nerve-sparing patients demonstrated superior functional outcomes compared with bilateral non–nerve-sparing patients, whereas bilateral nerve-grafting patients displayed a trend toward functional improvement. With increasing D’Amico score, there was a trend toward worsening urinary continence and erectile function regardless of nerve-grafting status.

Conclusions:

In the era of robotic prostatectomy, interpositional nerve reconstruction is not a routine practice. However, the substantial morbidity experienced in patients with bilateral nerve resections remains unacceptable, and therefore, nerve grafting may still improve functional outcomes in these patients. Further investigation is needed to improve the potential of bilateral nerve grafting after non–nerve-sparing 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.

Three-year outcomes of recovery of erectile function after open radical prostatectomy with sural nerve grafting

INTRODUCTION

Optimal oncologic control of higher stage prostate cancers often requires sacrificing the neurovascular bundles (NVB) with subsequent postoperative erectile dysfunction (ED), which can be treated with interposition graft using sural nerve.

AIMS

To examine the long term outcome of sural nerve grafting (SNG) during radical retropubic prostatectomy (RRP) performed by a single surgeon.

METHODS

Sixty-six patients with clinically localized prostate cancer and preoperative International Index of Erectile Function (IIEF) score >20 who underwent RRP were included. NVB excision was performed if the risk of side-specific extra-capsular extension (ECE) was >25% on Ohori' nomogram. SNG was harvested by a plastic surgeon, contemporaneously as the urologic surgeon was performing RRP. IIEF questionnaire was used pre- and postoperatively and at follow-up.

MAIN OUTCOME MEASURES

Postoperative IIEF score at three years of men undergoing RRP with SNG. Recovery of potency was defined as postoperative IIEF-EF domain score >22.

RESULTS

There were 43 (65%) unilateral SNG and 23 (35%) bilateral SNG. Mean surgical time was 164 minutes (71 to 221 minutes).The mean preoperative IIEF score was 23.4+1.6. With a mean follow-up of 35 months, 19 (28.8%) patients had IIEF score >22. The IIEF-EF scores for those who had unilateral SNG and bilateral SNG were 12.9+4.9 and 14.8+5.3 respectively. History of diabetes (P=0.001) and age (P=0.007) negatively correlated with recovery of EF. 60% patients used PDE5i and showed a significantly higher EF recovery (43% vs. 17%, P=0.009).

CONCLUSIONS

SNG can potentially improve EF recovery for potent men with higher stage prostate cancer undergoing RP. The contemporaneous, multidisciplinary approach provides a good quality graft and expedited the procedure without interrupting the work-flow.

Tissue engineering and stem cells: basic principles and applications in urology

To overcome problems of damaged urinary tract tissues and complications of current procedures, tissue engineering (TE) techniques and stem cell (SC) research have achieved great progress. Although diversity of techniques is used, urologists should know the basics. We carried out a literature review regarding the basic principles and applications of TE and SC technologies in the genitourinary tract. We carried out MEDLINE/PubMed searches for English articles until March 2010 using a combination of the following keywords: bladder, erectile dysfunction, kidney, prostate, Peyronie's disease, stem cells, stress urinary incontinence, testis, tissue engineering, ureter, urethra and urinary tract. Retrieved abstracts were checked, and full versions of relevant articles were obtained. Scientists have achieved great advances in basic science research. This is obvious by the tremendous increase in the number of publications. We divided this review in two topics; the first discusses basic science principles of TE and SC, whereas the second part delineates current clinical applications and advances in urological literature. TE and SC applications represent an alternative resource for treating complicated urological diseases. Despite the paucity of clinical trials, the promising results of animal models and continuous work represents the hope of treating various urological disorders with this technology.

Interposition nerve grafting during radical prostatectomy: cumulative review and critical appraisal of literature

In 1997, the first report of sural nerve interposition grafting during radical prostatectomy was published in Urology. The favorable findings in this initial pilot study generated numerous follow-up reports that have demonstrated conflicting and contradictory outcomes. Certainly, controversy exists regarding the true benefit of nerve grafting. This review will objectively and critically summarize the salient literature, discuss evolving techniques, and offer insight into the future of interposition grafting in the current era of clinically localized prostate cancer and robotic prostatectomy.

Randomized phase II trial evaluation of erectile function after attempted unilateral cavernous nerve-sparing retropubic radical prostatectomy with versus without unilateral sural nerve grafting for clinically localized prostate cancer

BACKGROUND

Nonrandomized studies of unilateral nerve-sparing (UNS) radical prostatectomy (RP) have reported improved recovery of erectile function if the sacrificed cavernous nerve is reconstructed with a sural nerve graft (SNG).

OBJECTIVE

To determine whether UNS RP plus SNG results in a 50% relative increase in potency at 2 yr compared to UNS RP alone.

DESIGN, SETTING, AND PARTICIPANTS

The study enrolled patients from October 2001-May 2006 from a single academic center and was randomized, open label. Participants were men with localized prostate cancer recommended for UNS RP, less than 66 yr old, normal baseline erectile function, and willing to participate in early erectile dysfunction (ED) therapy. Patients were followed up to 2 yr.

INTERVENTION

Patients underwent UNS RP and ED therapy starting at 6 wk: oral prostaglandin type-5 (PDE5) inhibitor, vacuum erection device (VED), and intracavernosal injection therapy. In the SNG group, a plastic surgeon performed the procedure at the time of RP.

MEASUREMENTS

The ability to have an erection suitable for intercourse with or without a PDE5 inhibitor at 2 yr. The hypothesis was that SNG would result in a 60% potency rate compared to 40% for controls (80% power, 5% two-way significance).

RESULTS AND LIMITATIONS

The trial planned to enroll 200 patients, but an interim analysis at 107 patients met criteria for futility and the trial was closed. For patients completing the protocol to 2 yr, potency was recovered in 32 of 45 (71%) of SNG and 14 of 21 (67%) of controls (p=0.777). By intent-to-treat analysis, potency recovered in 32 of 66 (48.5%) of SNG and 14 of 41 (34%) of controls (p=0.271). No differences were seen in time to potency or quality of life scores for ED and urinary function. Limitations included slower-than-expected accrual and poor compliance with ED therapy: <65% for VED and <40% for injections.

CONCLUSIONS

The addition of SNG to a UNS RP did not improve potency at 2 yr following surgery.

TRIAL REGISTRATION

ClinicalTrials.gov, Identifier: NCT00080808, http://www.clinicaltrials.gov/ct2/show/NCT00080808?term=NCT00080808&rank=1.

Recovery of erectile function after unilateral and bilateral cavernous nerve interposition grafting during radical pelvic surgery

PURPOSE

The use of cavernous nerve interposition grafting to preserve erectile function in men who require neurovascular bundle resection for cancer control is controversial. We report outcomes and predictors of cavernous nerve interposition grafting in men undergoing unilateral grafting during radical prostatectomy or bilateral grafting during radical cystectomy and prostatectomy with autologous nerve grafts.

MATERIALS AND METHODS

We retrospectively reviewed the electronic records of 36 patients who underwent cavernous nerve interposition grafting between 2003 and 2006. Postoperatively erectile function was assessed with the International Index of Erectile Function 15-item questionnaire. Predictors of potency, including age at surgery, time since surgery and prostate specific antigen at surgery, were assessed by univariate analysis.

RESULTS

A total of 33 patients (92% response rate) were followed for a median of 32, 25 and 11 months after bilateral grafting during radical cystectomy (10), unilateral grafting during radical prostatectomy (20), and bilateral grafting during radical cystectomy and prostatectomy (3), respectively. The rate of potency, defined as the ability to attain and maintain erection sufficient for penetration at least 50% of the time with or without phosphodiesterase-5 inhibitors, was 31% (5 of 13 men) for unilateral grafts, 38% (5 of 16) for bilateral grafts and 30% (3 of 10) for bilateral grafts during radical cystectomy. Age at surgery was the only significant determinant of potency and it showed an inverse relationship in the bilateral nerve graft group (p = 0.02).

CONCLUSIONS

Cavernous nerve interposition grafting appears to have a role in the recovery of erectile function. To our knowledge this study represents the largest series of cavernous nerve interposition grafting during cystectomy and it suggests that this should be considered during bilateral neurovascular bundle resection.

Results of unilateral genitofemoral nerve grafts with contralateral nerve sparing during radical prostatectomy

OBJECTIVES

To evaluate the success of erectile function preservation and recovery in a select group of patients with extensive disease unilaterally on biopsy who were candidates for unilateral nerve sparing and contralateral genitofemoral interposition nerve-grafting radical prostatectomy (RP). Because of its low donor site morbidity, the genitofemoral nerve is an appealing donor source for cavernous nerve grafting during RP. Although evidence has shown that sural interposition nerve grafts during RP preserve erectile function, the evidence for genitofemoral nerve grafts is limited.

METHODS

Nerve-sparing RP was performed according to the technique of Walsh on 22 patients with prostate cancer. At follow-up, the patients completed an 11-item self-report questionnaire that included the erectile function (EF) domain of the International Index of Erectile Function.

RESULTS

The mean patient age was 62 years (range 48 to 76). The mean follow-up time was 23 months (range 9 to 37). Of the 22 patients, 3 reported no erectile dysfunction (ED) (EF score 26 to 30), 3 reported mild ED (EF score 22 to 25), 1 reported moderate ED (EF score 11 to 16), and 15 reported severe ED (EF score less than 11). Eight men continued to experience mild chronic thigh or scrotal numbness after the genitofemoral nerve graft procedure.

CONCLUSIONS

The benefits of unilateral nerve grafting with the genitofemoral nerve remain uncertain. A prospective randomized trial is warranted before the widespread adoption of unilateral nerve grafting.

Preliminary Report of the Effect of High-Dose Adjuvant Intensity Modulated Radiation Therapy on the Sural Nerve Graft for Cavernosal Nerve Sacrifice After Radical Prostatectomy

PURPOSE

A sural nerve graft may replace a killed cavernosal nerve. The effect of intensity-modulated radiation therapy (IMRT) on function of the graft has not been reported.

MATERIALS AND METHODS

Between 1998 and 2001, 8 patients (9 nerve grafts) were treated with postoperative IMRT (mean dose, 70 Gy). Two patients had neoadjuvant Lupron 30 mg 2 months prior to radiation. Potency was defined as ability to achieve spontaneous erection sufficient for vaginal penetration. Median follow-up was 31.6 months.

RESULTS

Five patients (62.5%) who had erectile function after prostatectomy preserved spontaneous erectile function after radiation. Of these, 3 patients had both nerves resected (two receiving unilateral grafts and one receiving bilateral grafts) and 2 others had one graft and one nerve preserved. The impotent patients were impotent after surgery.

CONCLUSION

High-dose postprostatectomy IMRT does not place sural nerve grafts at greater risk for failure. Larger numbers of patients are needed to confirm these encouraging, preliminary findings.

Dissociation of sexual function and sexual bother following autologous sural nerve grafting during radical prostatectomy

AIM

We prospectively investigated health-related quality of life (HR-QOL), including sexual function and sexual bother, in patients who underwent nerve grafting during a radical prostatectomy in comparison with those who underwent a non-nerve-sparing radical prostatectomy.

METHODS

Between August 2001 and May 2004, radical prostatectomies were performed on 69 patients with clinical T1-T2N0/M0 prostate cancer. Of these, 66 patients (22: nerve-grafting patients, 44: non-nerve-sparing and non-nerve-grafting patients) were enroled into this study. The observation periods ranged from 12-46 months (median: 29 months). The general HR-QOL was measured with the SF-36 General Health Survey and disease-specific HR-QOL was measured with the University of California Los Angeles-Prostate Cancer Index.

RESULTS

Penile tumescence was observed in 11 out of 15 (73.3%) prostate-specific antigen failure-free patients who underwent unilateral nerve grafting with contra-lateral nerve-sparing or bilateral nerve grafting. Vaginal penetration was observed in six out of 15 (40.0%) patients. The time for partial erection and for intercourse, respectively, ranged from 3-21 months (median = 6 months) and 6-36 months (median = 13.5 months). There were no significant differences in general HR-QOL changes over time between the nerve-grafting patients and the patients without any nerve-preserving procedures. The sexual function score was significantly better in the nerve-grafting (bilateral nerve graft or unilateral nerve graft with contra-lateral nerve-sparing) patients than in the non-nerve-sparing/non-nerve-grafting patients. The sexual bother score, however, was more serious for the patients who underwent nerve-grafting surgery than for the non-nerve-sparing/non-nerve-grafting patients.

CONCLUSION

Sexual bother is serious for patients who attempt to maintain sexual function after special surgical procedures, such as nerve-grafting surgery. We should be aware that careful counseling is needed to avoid impatient and excessive hope for the recovery of sexual function.

Cavernous nerve graft reconstruction using an autologous nerve guide to restore potency

OBJECTIVE

To present our experience of cavernous nerve graft reconstruction, using an autologous nerve vein-guide technique, to restore potency.

PATIENTS AND METHODS

Prostate cancers frequently require radical resection involving one or both cavernous nerves that usually results in erectile dysfunction; nerve grafting has been used to restore erectile function, but clinical results are unsatisfactory owing to inadequate surgical techniques. In all, eight patients with prostate cancer who required radical resection involving one cavernous nerve had sural nerve grafting, with two or three sutures using the autologous vein-guide technique, in our unit between 2004 and 2005. Because of the difficulty of performing microsurgical manoeuvres deep within the pelvic cavity, the nerve anastomosis might be unsatisfactory.

RESULTS

Seven of the eight patients had spontaneous erectile activity after grafting and six of these patients were able to have intercourse.

CONCLUSION

Sural nerve grafting using the autologous vein-guide technique is simple, has minimal morbidity, and yields good outcomes.

Bilateral Cavernous Nerve Interposition Grafting During Radical Retropubic Prostatectomy: Memorial Sloan-Kettering Cancer Center Experience

PURPOSE

Cavernous nerve graft is an option for men requiring bilateral cavernous nerve resection for cancer control during radical prostatectomy. We determined the success rate and identified determinants of success of bilateral cavernous nerve grafting following resection of the 2 nerves during radical prostatectomy in patients who were potent preoperatively.

MATERIALS AND METHODS

We retrospectively reviewed the records of 44 consecutive patients who underwent bilateral nerve grafting from 1999 to 2004. Postoperative erectile function was defined as the achievement of erections satisfactory for intercourse with or without oral medication. We calculated cumulative erectile function recovery rates using Kaplan-Meier curves. The log rank test was used to compare variables affecting erectile function recovery with p <0.0083 considered significant after adjusting for the number of variables evaluated using the Bonferroni correction.

RESULTS

The overall 5-year cumulative recovery of erectile function permitting penetration was 34% and the rate of consistent penetration was 11%. None of the analyzed variables were significantly associated with recovery of postoperative erectile function, including patient age (p = 0.3), incomplete bilateral cavernous nerve resection (p = 0.045), sural nerve grafts compared to genitofemoral or ilioinguinal nerves as donor sites (p = 0.067), post-radiation salvage radical prostatectomy (p = 0.15), neoadjuvant hormone therapy (p = 0.7) and comorbidities (p = 0.15) or medications (p = 0.4) affecting EF.

CONCLUSIONS

Bilateral cavernous nerve grafts might be beneficial in select patients. A definitive answer awaits the performance of a multi-institutional, randomized, controlled trial.

Reconstruction of cavernous nerves by nerve grafts to restore potency: contemporary review of technical principles and basic anatomy

PURPOSE OF REVIEW

The review discusses the efficacy of reconstructing the neurovascular bundle to regain sexual function if nerve-sparing prostatectomy is unfeasible.

RECENT FINDINGS

Eleven studies could be found describing the reconstruction of neurovascular bundles. All reconstructive procedures displayed technical inadequacies. The effectiveness of unilateral neurovascular bundle reconstruction remains statistically insignificant when compared with procedures without reconstruction. The efficacy of reconstructing both neurovascular bundles ranges between 0 and 43%. Concerning basic anatomy, the neurovascular bundle contains fibers innervating the cavernous nerves, prostate, rectum, and levator ani muscle. The terms cavernous nerve and neurovascular bundle have often been wrongly considered synonymous. The pelvic splanchnic nerves probably do not join the neurovascular bundle proximal to the bladder/prostate junction but rather at variable distances from 10 to 20 mm distal to it. Therefore, described proximal coaptation sites at the bladder/prostate junction possibly encompass only the hypogastric nerve.

SUMMARY

Modest clinical results are partly due to inadequate surgical techniques and are mainly due to the anatomical and topographical complexity of the cavernous nerves. Contemporary nerve grafting techniques probably do not allow for the regeneration of all cavernous nerves.

The Effects of Cavernous Nerve Grafting following Surgically Induced Loss of Erectile Function in a Large-Animal Model

BACKGROUND

Prostate cancer is the second most common cause of cancer deaths in men in the United States. Many patients experience partial or complete loss of erectile function following prostatectomy. The cavernous nerves can be reconstructed intraoperatively using sural nerve grafts in an attempt to restore erectile function.

METHODS

In this study, multiple anatomical dissections and neurologic assessments were used to define the position and histologic parameters of the cavernous nerve in a canine model. The subsequent experimental design included three groups of adult mongrel dogs followed for an 8-month period. Group 1, the control group, underwent bilateral nerve ablation to substantiate surgically induced loss of erectile function. Group 2, the "sham" group, underwent exploration only. Group 3 underwent bilateral cavernous nerve ablation with bilateral sural nerve graft reconstruction. Erectile function was evaluated with indirect electrical nerve and manual penile stimulation preoperatively and 1, 2, 4, 6, and 8 months postoperatively. Direct nerve stimulation and histologic analysis was preformed at the first operation and at the time the animals were euthanized at 8 months.

RESULTS

Bilateral cavernous nerve ablation resulted in a significant loss of erectile function for 8 months postoperatively in the control animals. The sham animals demonstrated preservation of erectile function immediately following exploration. The animals in the grafted group demonstrated a significant return of erectile function by 4 months compared with preoperative measurements and by 2 months compared with control animals.

CONCLUSIONS

This study establishes the first large-animal model for surgically induced loss of erectile function with successful cavernous nerve graft reconstruction, and it provides the unique opportunity to explore the effects of changes to this model in the future.

Update on erectile dysfunction in prostate cancer patients

PURPOSE OF REVIEW

Evolution in the management of prostate cancer includes increased attention being paid to patient quality of life after treatment, specifically with issues related to sexual function. Erectile dysfunction is one of the major concerns of patients undergoing treatment for prostate cancer. There are several recognized factors that determine the postoperative incidence of erectile difficulties, including patient age, degree of cavernosal nerve sparing during surgery, cancer stage, and associated vascular comorbidities. Early initiation of rehabilitation protocols after radical prostatectomy has been advocated to promote the speed and degree of recovery of erectile function. The aim of this communication is to review recent initiatives in erectile dysfunction restoration after prostate cancer therapy.

RECENT FINDINGS

In recognition of the neurogenic basis of erectile dysfunction after radical prostatectomy, new strategies have been devised to initiate the rehabilitation process. Type 5 phosphodiesterase inhibitors, vacuum erection devices, and intracavernosal and intraurethral application of vasoactive agents have all been reported in a positive light in recent studies. Developments in cavernous nerve graft interposition procedures, perioperative neuroprotection measures, and postoperative neurotrophic treatments aim to preserve prostate cancer patients' qualities of life.

SUMMARY

Data generated from a number of clinical investigations document that pharmacologic rehabilitation programs provide a higher rate of recovery of erectile function following radical prostatectomy. Both intracavernosal and intraurethral applications of vasoactive agents and vacuum devices can speed the recovery period for return of erectile function. Various neuroprotective and neurotrophic approaches are thought to provide integral roles for the maintenance of sexual function in men undergoing prostate cancer therapy.

Surgery for locally advanced disease

Locally advanced prostate cancer is diagnosed in approximately one in four new cases of prostate cancer. The estimated disease-specific mortality rate resulting from monotherapy with either surgery or radiotherapy is a disappointing 75%. A multimodality treatment approach could offer more promising results. In addition, several key factors related to surgical treatment of locally advanced prostate cancer may optimize the oncologic results and minimize patient morbidity. In this report, we summarize some of the anatomic features and technical concepts associated with the surgical management of this disease and review recently published results of the outcomes of surgery and neoadjuvant or adjuvant chemohormonal therapy for locally advanced prostate cancer.

Morbidity and efficacy of genitofemoral nerve grafts with radical retropubic prostatectomy

OBJECTIVES

To review our experience with genitofemoral nerve grafting after radical prostatectomy, to determine both morbidity and efficacy.

METHODS

We identified patients who underwent genitofemoral nerve grafting between 2001 and 2003 at our hospital. Morbidity was recorded prospectively in the charts, and a validated questionnaire (International Index of Erectile Function, IIEF-5) was used to determine erectile function.

RESULTS

Twenty-seven patients received 32 genitofemoral nerve grafts. Five patients (19%) received bilateral grafts. In 3, a single nerve was harvested for a bilateral graft. Mean graft length was 5 cm, and mean follow-up was 14 months. Two patients (7%) reported persistent, minor numbness or tingling of the ipsilateral thigh or hemiscrotum. No other morbidity was noted. Overall, 56% of the patients were able to sustain an erection with enough firmness for penetration at the time of follow-up. Of those patients who reported no preoperative erectile dysfunction, 69% were able to have sexual intercourse.

CONCLUSIONS

Harvesting and interposition of genitofemoral nerve grafts in the neurovascular bundle adds very minimal morbidity to radical prostatectomy. The results reported in our patients are at least comparable to those achieved with sural nerve grafting. Whether these results are a consequence of an effective unilateral nerve-sparing dissection or the nerve grafting itself is uncertain.

Hope springs eternal: cavernosal nerve regeneration

Erectile dysfunction after radical prostatectomy for prostate cancer remains a significant morbidity for a large group of patients. A large body of work suggests that disrupting the cavernosal nerves is central as a causative factor. Extensive research has focused on ways to increase potency rates after surgery, either by preserving neuro-integrity, or attempting to restore it using various approaches. Herein we discuss the neurophysiology of nerve injury and regeneration, and review the work to date on cavernosal nerve regeneration.

Recent neuroanatomical studies on the neurovascular bundle of the prostate and cavernosal nerves: clinical reflections on radical prostatectomy

The neurovascular bundle of the prostate and cavernosal nerves have been used to describe the same structure ever since the publication of the first studies on the neuroanatomy of the lower urogenital tract of men, studies that were prompted by postoperative complications arising from radical prostatectomy. In urological surgery every effort is made to preserve or restore the neurovascular bundle of the prostate to avoid erectile dysfunction (ED). However, the postoperative potency rates are yet to be satisfactory despite all advancements in radical prostatectomy technique. As the technology associated with urological surgery develops and topographical studies on neuroanatomy are cultivated, new observations seriously challenge the classical teachings on the topography of the neurovascular bundle of the prostate and the cavernosal nerves. The present review revisits the classical and most recent data on the topographical anatomy of the neurovascular bundle of the prostate and cavernosal nerves and their implications on radical prostatectomy techniques.

Feasibility study for robotic radical prostatectomy cautery-free neurovascular bundle preservation

INTRODUCTION

Efforts continue to develop techniques that maintain the neurovascular bundles and minimize trauma for robotic laparoscopic radical prostatectomy. We evaluated the feasibility of preserving the nerve bundles without cautery or surgical clips.

TECHNICAL CONSIDERATIONS

The seminal vesicles were dissected using scissors and bipolar cautery. After the rectum was mobilized, the vascular pedicles (VPs) were delineated. Laparoscopic bulldog clamps (30 mm) were placed at least 1 cm from the prostate. Using scissors, the VPs were divided right at the prostate. The neurovascular bundle was gently dissected off the prostatic capsule. After mobilizing the bundle, FloSeal was applied along its entire length. The FloSeal was then covered with a dry 1 x 4-cm sheet of Gelfoam. Once the prostate was removed, the bulldog clamps were sequentially withdrawn. The VPs were observed, and, if pulsatile bleeding was encountered, a 3-0 figure-of-eight suture was precisely placed for hemostasis. When hemostasis was complete, the anastomosis was performed.

RESULTS

In 17 men, temporary vascular occlusion was applied to 27 VPs and FloSeal and Gelfoam was applied each time. In 4 cases (15%), hemostasis was inadequate because of continued arterial bleeding that was easily controlled with a superficial figure-of-eight ligature of 3.0 absorbable suture. The average estimated blood loss was 91 mL (range 75 to 150).

CONCLUSIONS

Cautery-free, clip-free, nerve-sparing robotic laparoscopic radical prostatectomy is feasible using a combination of temporary occlusion of the thick posterior prostatic pedicles with bulldog clamps followed by application of FloSeal. The effect on potency needs further follow-up.

Recent trends in surgical treatment of localized prostate cancer

Prostate cancer and its various forms of treatment remain a source of significant controversy and morbidity despite recent advances. In response, there is an increasing trend toward the development of treatments aimed at cancer prevention and at maximizing the preservation of function without sacrificing cancer control. This article reviews the current prostate cancer literature and reports on improvements in existing surgical treatments and developing technologies aimed toward achieving these goals. Specific therapies addressed include improvements in surgical techniques, laparoscopy, robotics, cryosurgical and thermal ablation, and high-intensity focused ultrasound.

[Nerve repair strategies for restoration of erectile function after radical pelvic surgery]

Iatrogenic cavernous nerve lesions occurring during radical pelvic surgery often lead to irreversible erectile dysfunction. The nerve defects after excision of the neurovascular bundles must be reconstructed by interposition grafting to supply a permissive scaffold for oriented axonal regrowth. The use of autologous nerve grafts for the repair of human cavernous nerves during radical prostatectomy has been controversial regarding the limited success achieved with bilateral nerve grafting. Artificial nerve guides consisting of natural or synthetic materials have been successfully used for bridging peripheral nerve defects. The combination with Schwann cells, neurotrophic factors and extracellular matrix components has been shown to promote cavernous nerve regeneration.

Current concepts in the management of erectile dysfunction in men with prostate cancer

Development in the management of prostate cancer has placed increased attention on patient quality of life after treatment, particularly sexual function. The incidence of erectile dysfunction (ED) in men following radical prostatectomy has been estimated to range from 16% to 82%. Several factors determine the postoperative incidence of erectile difficulties; these include patient age, degree of cavernosal nerve sparing during surgery, cancer stage, and associated comorbidities. Early initiation of available treatments after radical prostatectomy, such as phosphodiesterase-5 (PDE-5) inhibitors and intracavernosal alprostadil, may improve the speed and degree of recovery of erectile function. Oral PDE-5 inhibitors are recognized as the first line of therapy for men with ED after radical prostatectomy, with reasonable success rates reported for all commercially available PDE-5 inhibitors. In recognition of the neurogenic basis for erectile dysfunction after radical prostatectomy, new strategies have been devised, such as cavernous nerve graft interposition procedures, perioperative neuroprotection measures, and postoperative neurotrophic treatments. Hopefully, these efforts will improve quality of life for patients with prostate cancer. The aim of this article is to review the current modalities of ED management for men with prostate cancer.

Current and Future Strategies for Preventing and Managing Erectile Dysfunction Following Radical Prostatectomy

INTRODUCTION AND OBJECTIVES

As radical prostatectomy remains a commonly used procedure in the treatment of clinically localized prostate cancer, we critically analyzed current and future strategies for preventing and managing postoperative erectile dysfunction.

METHODS

Systematic literature review using Medline and CancerLit from January 1997 to June 2003. Abstracts published in the journals European Urology, The Journal of Urology and the International Journal of Impotence Research as official proceedings of internationally known scientific societies held in the same time period were also assessed.

RESULTS

Patient selection and surgical technique are the major determinants of postoperative erectile function. Apoptosis of corporeal smooth muscle cells plays a role in the development of cavernous veno-occlusive dysfunction following radical prostatectomy. Pharmacological prophylaxis and treatment of postoperative erectile dysfunction is effective and safe. The concepts of cavernous nerve reconstruction and neuroprotection have been associated to promising results.

CONCLUSIONS

In the hands of experienced surgeons, properly selected patients undergoing a nerve sparing radical prostatectomy should achieve unassisted or medically assisted erections postoperatively.