Basic principles of anatomy for optimal surgical treatment of prostate cancer

The treatment of prostate cancer (PCa) with nerve sparing radical prostatectomy (NSRP) has experienced a substantial improvement in recent years due to new insights in anatomy of the prostate and of the adjacent structures. Knowledge of this specific anatomy is mandatory during RP in order to avoid injuries to functional tissue. Above all, these tissues are the neurovascular bundle (NVB) and the urethral sphincter. We therefore reviewed the available literature on prostatic anatomy and summarized it in this article. A search of the PubMed database was performed using the keywords radical prostatectomy, anatomy, neurovascular bundle, fascia, pelvis and sphincter. Relevant articles were reviewed, analyzed and summarized. This article gives an insight in the anatomy of the NVB, the urethral sphincter and the fascias surrounding the prostate. The NVB might be hampered near the seminal vesicles, at the lateral surface of the prostate and in the area of the prostato-urethral junction. The urethral sphincter might be hampered during dissection of the dorsal vein complex and during dissection of the urethra at the prostatic apex. Finally, the anatomy of the fascias surrounding the prostate is complex and can inter-individually vary substantially, which adds to the technical difficulties of NSRP. With this article we provide an overview on the complex anatomy of the prostate and the adjacent tissues. Respecting and considering these anatomic principles during NSRP should result in good postoperative functional outcome, as well as in good outcome in cancer control.     

Laparoscopic radical prostatectomy: current techniques

PURPOSE OF REVIEW: Laparoscopic radical prostatectomy is now considered the standard of care at many centers for the treatment of localized prostate cancer. As with other surgical approaches, there has been an evolution in surgical techniques. Critical evaluation of the effects of these changes on clinical and pathologic outcomes continues. RECENT FINDINGS: The technique of nerve sparing laparoscopic radical prostatectomy should attempt to mimic the techniques and outcomes of open surgery, while maintaining the advantages of reduced blood loss and morbidity, and greater visualization. Long-term functional and oncologic outcomes appear equivalent to open surgery. Surgical approaches based upon recent anatomic studies of the periprostatic neuroanatomy continue to spur both advances and debate. Athermal dissection near the neurovascular bundle, along with high release of the surrounding fascia, may hasten recovery of erectile function. Techniques of sparing or reconstructing the puboprostatic ligaments and support of the bladder are evolving in efforts to improve continence results. Debate over the merits of transperitoneal vs. extraperitoneal approaches to laparoscopic prostatectomy continues. SUMMARY: Nerve sparing laparoscopic radical prostatectomy, although technically challenging, has proven to be an excellent alternative for dedicated centers wishing to provide a minimally invasive surgical option to their patients with localized prostate cancer.     

Intrafascial nerve-sparing endoscopic extraperitoneal radical prostatectomy

OBJECTIVES: Based on our recently published anatomic studies, we present the most recent refinement of the endoscopic extraperitoneal radical prostatectomy (EERPE), the intrafascial nerve-sparing EERPE (nsEERPE). METHODS: As part of the intrafascial technique, the dissection plane is directly on the prostatic capsule, freeing the prostate laterally from its thin surrounding fascia that contains small vessels and nerves. The technique enables puboprostatic ligament preservation, leaving intact endopelvic fascia, periprostatic fascia, and neurovascular bundles. The operation was performed in 150 patients with indications for nerve-sparing procedure. RESULTS: The mean operative time was 131 min (range: 50-210 min) and the mean catheterization time was 5.9 d (range: 4-20 d). Twelve months postoperatively, 94.3% of the patients were continent (no need for pads), 4.6% had minimal stress incontinence, and one patient required >2 pads/d. At the 12-mo follow-up, the potency rates (erections sufficient for intercourse with or without the use of phosphodiesterase 5 [PDE5] inhibitors) of the patients who underwent bilateral intrafascial nsEERPE were 89.7% (age: 44-55 yr), 81.1% (age: 56-65 yr), and 61.9% (age: >65 yr). Positive surgical margins in pT2 and pT3 tumors were 4.5% and 29.4%, respectively. CONCLUSIONS: The intrafascial nsEERPE enables the dissection of the prostate with limited trauma to the surrounding fascias and the enclosed neurovascular bundles. We propose that the preserved neurovascular bundles with intrafascial nsEERPE are more viable. The results advocate this proposition.     

New method to improve treatment outcomes for radical prostatectomy

Modifications in radical retropubic prostatectomy that use the deep dorsal vein ligator and either anterior urethropexy or puboprostatic ligament preservation were developed to reduce blood loss and improve continence results. Use of the deep dorsal vein ligator to secure the deep dorsal vein complex also improves visualization of the urethra for transection and the neurovascular bundle for nerve sparing and thereby may assist in laparoscopic radical retropubic prostatectomy.     

A Critical Analysis of the Current Knowledge of Surgical Anatomy Related to Optimization of Cancer Control and Preservation of Continence and Erection in Candidates for Radical Prostatectomy

Context

Detailed knowledge of the anatomy of the prostate and adjacent tissues is mandatory during radical prostatectomy to ensure reliable oncologic and functional outcomes.

Objective

To review critically and to summarize the available literature on surgical anatomy of the prostate and adjacent structures involved in cancer control, erectile function, and urinary continence.

Evidence acquisition

A search of the PubMed database was performed using the keywords radical prostatectomy, anatomy, neurovascular bundle, fascia, pelvis, and sphincter. Relevant articles and textbook chapters were reviewed, analyzed, and summarized.

Evidence synthesis

Anatomy of the prostate and the adjacent tissues varies substantially. The fascia surrounding the prostate is multilayered, sometimes either fused with the prostate capsule or clearly separated from the capsule as a reflection of interindividual variations. The neurovascular bundle (NVB) is situated between the fascial layers covering the prostate. The NVB is composed of numerous nerve fibers superimposed on a scaffold of veins, arteries, and variable amounts of adipose tissue surrounding almost the entire lateral and posterior surfaces of the prostate. The NVB is also in close, cage-like contact to the seminal vesicles. The external urethral sphincter is a complex structure in close anatomic and functional relationship to the pelvic floor, and its fragile innervation is in close association to the prostate apex. Finally, the shape and size of the prostate can significantly modify the anatomy of the NVB, the urethral sphincter, the dorsal vascular complex, and the pubovesical/puboprostatic ligaments.

Conclusions

The surgical anatomy of the prostate and adjacent tissues involved in radical prostatectomy is complex. Precise knowledge of all relevant anatomic structures facilitates surgical orientation and dissection during radical prostatectomy and ideally translates into both superior rates of cancer control and improved functional outcomes postoperatively.     

Intraoperative nerve stimulation with measurement of urethral sphincter pressure changes during radical retropubic prostatectomy: a feasibility study

PURPOSE: We evaluated the feasibility of using intraoperative nerve stimulation and real-time urodynamic monitoring to identify the intrapelvic innervation of the urethral sphincter during radical retropubic prostatectomy. MATERIALS AND METHODS: Using an intraurethral balloon pressure transducer and nerve stimulator changes in urethral pressure were measured in response to stimulation of the neurovascular bundles, pelvic side wall, bladder neck, rectus muscle and other structures in 8 patients undergoing nerve sparing radical retropubic prostatectomy. Intraurethral pressure changes were charted on an urodynamic monitor and correlated with the anatomical location of stimulation. RESULTS: Stimulation of the neurovascular bundles resulted in measurable and significant (greater than 10 cm. H(2)O) increases in intraurethral pressure in all 8 patients. The mean pressure increase was 22 cm. H(2)O. Neither control structure, that is the bladder neck or rectus, resulted in pressure changes with stimulation. In 60% of the subjects pelvic side wall stimulation resulted in urethral pressure increases, while in 40% this stimulation caused pelvic contraction floor but no pressure increase. The mean pressure changes with side wall stimulation was 14 cm. H(2)O. CONCLUSIONS: Intraoperative stimulation of pelvic neural structures and measurement of changes in urethral pressure in response to stimulation are feasible during radical retropubic prostatectomy. Stimulating the neurovascular bundle consistently results in significant increases in urethral pressure. The finding of an intrapelvic urethral innervation supports the previously published observation that nerve sparing radical retropubic prostatectomy may result in improved continence postoperatively.     

Urinary incontinence after robot‐assisted radical prostatectomy: Pathophysiology and intraoperative techniques to improve surgical outcome

Robot‐assisted radical prostatectomy has been shown to have comparable and possibly improved postoperative continent rates compared with retropubic and laparoscopic radical prostatectomy. However, postoperative urinary incontinence has remained one of the most bothersome postoperative complications. The basic concept of the intraoperative technique to improve postoperative urinary continence is to maintain as normal anatomical and functional structure in the pelvis as possible. Therefore, improved knowledge of the normal structure in the pelvis should lead to a greater understanding of the pathophysiology of urinary incontinence, and further development of intraoperative techniques to improve the outcomes of urinary continence. It might be necessary to carry out three steps to realize improvement of the early return of urinary continence after robot‐assisted radical prostatectomy: (i) preservation (bladder neck, neurovascular bundle, puboprostatic ligament, pubovesical complex, and/or urethral length, etc.); (ii) reconstruction (posterior and/or anterior reconstruction, and/or reattachment of the arcus tendineus to the bladder neck, etc.); and (iii) reinforcement (bladder neck plication and/or sling suspension, etc.). On the basis of these steps, further modifications during robot‐assisted radical prostatectomy should be developed to improve urinary continence and quality of life after robot‐assisted radical prostatectomy.     

Surgical anatomy of the puboprostatic complex with special reference to radical perineal prostatectomy

OBJECTIVE: To investigate the retropubic space and attachments of the prostate and urethra, with special reference to radical perineal prostatectomy. MATERIALS AND METHODS: Anatomical relationships were assessed intraoperatively in 60 patients, and in five cadavers after preparing the dorsal vein complex with coloured latex. Cross-sections of the area of interest were evaluated by microscopy. RESULTS: The puboprostatic (pubovesical) ligaments could be clearly distinguished from the median part of the puboprostatic complex continuous with the urethral suspensory mechanism. The dorsal vein complex is integrated into this fibromuscular attachment of the prostate and male urethra. During the perineal approach, dissection in this region follows the so-called avascular plane. CONCLUSION: With this new insight into the anatomical relationships the nomenclature derived from radical retropubic prostatectomy could be mirrored. In radical perineal prostatectomy, both the urethral suspensory mechanism and the dorsal vein complex can be preserved.     

Practical surgical anatomy for radical prostatectomy

Practical guidelines in surgical anatomy for radical prostatectomy can be summarized as follows: 1. There is significant individual variation in the anatomy of the male pelvis. 2. The prostate is covered anteriorly by a prominent detrusor apron. 3. Prostates vary with respect to size and shape. 4. BPH compresses and flattens the peripheral zone. 5. In reality, the puboprostatic ligaments are pubovesical ligaments. 6. The dorsal vein complex of the penis is a neurovascular plexus of veins, arteries, and nerves situated primarily ventral to the prostate and urethra. 7. The urethra from the verumontanum to the penile bulb is sphincteric, with its smooth muscle and elastic tissue components primarily responsible for postprostatectomy urinary continence. 8. Multiple micropedicles tether the neurovascular bundles along the entire posterolateral aspect of the prostate.     

Urodynamic evaluation of a suspension technique for rapid recovery of continence after radical retropubic prostatectomy

BACKGROUND: We investigated urodynamic findings involved in the rapid recovery of urinary continence after radical retropubic prostatectomy with a suspension technique. METHODS: A total of 45 consecutive patients (mean age 67.6 years) who had undergone radical retropubic prostatectomy for localized prostate cancer were evaluated with multichannel urodynamics including the maximal urethral pressure (MUP), functional urethral length (FUL), maximal cystometric capacity (MCC) and abdominal leak point pressure (ALPP) at base line, 1 week, 1 month, and 3 months postoperatively. The suspension of vesicourethral anastomosis preserving anterior attachments of puboprostatic ligaments to pubic bone was performed in 33 patients. Twelve patients did not undergo the suspension technique. RESULTS: The continence rates at 1 week, 1 month, and 3 months after radical prostatectomy in the suspension group were significantly higher than those in the non-suspension group: 67% versus 0% at 1 week (P < 0.001), 82% versus 25% at 1 month (P < 0.001), and 91% versus 50% at 3 months (P < 0.01), respectively. Postoperative ALPP at all points of measurement was significantly higher in the suspension group than in the non-suspension group (P < 0.0002). There was no difference in MUP, FUL or MCC at each point following radical prostatectomy between the two groups. CONCLUSIONS: These observations suggest that preserving anterior attachments of puboprostatic ligaments to pubic bone and fixation of urethral hyper-mobility by the suspension of vesicourethral anastomosis promotes rapid recovery of urinary continence after radical retropubic prostatectomy.     

A matched-pair comparison between bilateral intrafascial and interfascial nerve-sparing techniques in extraperitoneal laparoscopic radical prostatectomy

The aim of this study was to validate the advantages of the intrafascial nerve-sparing technique compared with the interfascial nerve-sparing technique in extraperitoneal laparoscopic radical prostatectomy. From March 2010 to August 2011, 65 patients with localized prostate cancer (PCa) underwent bilateral intrafascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy. These patients were matched in a 1∶2 ratio to 130 patients with localized PCa who had undergone bilateral interfascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy between January 2008 and August 2011. Operative data and oncological and functional results of both groups were compared. There was no difference in operative data, pathological stages and overall rates of positive surgical margins between the groups. There were 9 and 13 patients lost to follow-up in the intrafascial group and interfascial group, respectively. The intrafascial technique provided earlier recovery of continence at both 3 and 6 months than the interfascial technique. Equal results in terms of continence were found in both groups at 12 months. Better rates of potency at 6 months and 12 months were found in younger patients (age ≤65 years) and overall patients who had undergone the intrafascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy. Biochemical progression-free survival rates 1 year postoperatively were similar in both groups. Using strict indications, compared with the interfascial nerve-sparing technique, the intrafascial technique provided similar operative outcomes and short-term oncological results, quicker recovery of continence and better potency. The intrafascial nerve-sparing technique is recommended as a preferred approach for young PCa patients who are clinical stages cT1 to cT2a and have normal preoperative potency.     

Potency-Sparing Radical Retropubic Prostatectomy: A Simplified Anatomical Approach

A simplified method of nerve sparing radical retropubic prostatectomy for clinical stage T2a prostate cancer is described based on primary isolation of both neurovascular bundles and secondary division of the urethra, with the puboprostatic ligaments undivided to provide suspension of the deep venous complex above the urethra. The principles for this approach after division of the deep vein complex are based on early unilateral incision of the prostatic fascia laterally, parallel to the ipsilateral neurovascular bundle and extending from the proximal prostate to the urethra; separation of anterior (prostatic) and posterior (rectal) Denonvilliers' fascia, which leaves the neurovascular bundle invested in the latter tissue; perforation and incision of contralateral prostatic fascia at its urethroprostatic angle, with cranial extension of the fascial opening dropping the ipsilateral neurovascular bundle invested in its fascia (Denonvilliers' posterior), and anastomotic division of the urethra at its entrance into the prostate.     

Anatomy and physiology of the male urethral sphincter and its preservation in prostatic surgery

Radical prostatectomy is commonly used in the management of localized prostate cancer. Urinary incontinence after prostatectomy is of great concern to many patients. Improved understanding of the anatomy of the external urethral sphincter complex has resulted in a statistically significant decrease in the incidence of postprostatectomy incontinence. Most recent anatomic studies have described the external urethral sphincter complex as consisting of an intrinsic rhabdosphincter surrounding the smooth musculature of the urethra and an extrinsic sphincter incorporating the levator ani muscle and the pelvic floor. Both form a condensed striated muscle ring around the membranous urethra. Preservation of as much as possible of the normal anatomy of the sphincter mechanism and its nerve supply results in an excellent return to continence after radical prostatectomy. Received: 26 February 1999 / Accepted: 20 May 1999     

筋膜内切除法在腹腔镜下前列腺癌根治术中的应用

目的 探讨筋膜内切除法在腹腔镜下根治性前列腺切除术中的应用.方法 前列腺癌患者23例,平均年龄65岁.术前PSA 4.5～8.6(6.25 ±2.1)ng/ml;临床分期T1 16例、T2 7例;活检组织Gleason评分:5分3例、6分11例、7分9例.有性生活者18例.行腹腔镜下根治性前列腺切除术.不打开盆内筋膜,自前列腺基底部沿前部正中线纵形切开前列腺筋膜,贴前列腺包囊分离前列腺前面、两侧、尖部.保留神经血管束.保护前列腺尖尿道相连处括约肌.结果 23例手术顺利.平均手术时间125(110～170)min.出血量320～1500(550±210)ml,输血3例.平均留置尿管12(9～15)d.术后随访12个月,完全尿控20例(87%).有轻微压力性尿失禁3例(13%).18例术前有性生活的患者能充分勃起完成性交13例(72%).随访期间出现生化复发2例(9%).结论 腹腔镜下筋膜内切除法剥离前列腺对前列腺周围筋膜、附着于筋膜的神经血管束以及尿道外括约肌损伤小.手术方法可行.     

腹腔镜前列腺癌根治术术中实时盆底括约肌肌电监测的可行性研究

目的 通过在腹腔镜前列腺癌根治术中实时用NIM-ResponseTM肌电监测仪监测盆底括约肌电活动,了解控尿神经的分布,以便术中保护控尿神经,提高术后控尿效果;并对比手术前后患者控尿情况,评价实时监测技术在保护控尿神经方面的效果及意义.方法 80例前列腺癌患者临床分期为T2a~T3a纳入研究.将这些术前控尿正常的患者随机分成2组,每组40例.其中A组(神经监测组)利用NIM-ResponseTM肌电监测仪对以上患者腹腔镜前列腺癌根治术中盆底括约肌电活动进行术中实时监测.所有患者均采用气管全麻,避免术中使用肌松药.接地电极接于上臂,探测电极置于肛门括约肌及尿道括约肌.术中在前列腺邻近结构处以神经刺激探针以最高5 mA电流刺激和探测证实控尿神经在膀胱颈、前列腺、尿道周围行程及功能状态,通过避免电切电凝破坏控尿神经邻近结构达到保护其免受损伤的目的.B组(非神经监测组)行常规腹腔镜前列腺癌根治术.对比术前、术后拔尿管后24 h、术后3个月和术后6个月患者控尿情况,包括尿动力学检查、尿垫试验、膀胱镜检查.结果 术后两组拔尿管后24 h完全控尿率有显著差异(65.0%vs 37.5%,P<0.05)、术后3个月和术后6个月控尿率则无差异(80.0%vs 75.0%,P>0.05和92.5%vs 90.0%,P>0.05).术后30 d尿动力学检查证实80例患者前列腺部尿道控制带阻力消失,尿道闭合压正常存在,括约肌肌电正常存在.膀胱镜见40例患者尿道括约肌结构存在,镜下括约肌收缩功能良好.结论 腹腔镜前列腺癌根治术中采用盆底括约肌电活动实时监测,对控尿神经的解剖及功能分布有较强的准确性,可加快术后控尿功能恢复.     

提高腹腔镜前列腺癌根治术后控尿的临床研究

目的 分析总结腹腔镜前列腺癌根治术51例手术控尿技术的经验.方法 回顾性总结腹腔镜前列腺癌根治术患者51例.术前均病理证实前列腺癌诊断.T la～1b 4例(8%),T 1c 15例(29%),T2a 7例(14%),T2b 5例(10%),T2c 20例(39%).结果 腹腔镜下成功完成前列腺癌根治术49例.术后发生尿漏3例,均自愈.术后尿管留置14～45 d,平均16 d.术后随访3～53个月,平均17个月.术后3个月随访51例患者,13例尿失禁;术后6个月随访39例患者,7例尿失禁;术后12个月随访患者20例,5例尿失禁,其中完全性尿失禁1例.前20例和后31例在术后3个月时尿失禁发生率分别为6/20(30%)和7/31(22%),差异有统计学意义(P<0.05).直肠损伤2例,行结肠造口术.术后复发2例,一例行内分泌治疗后停药.另一例肺转移手术后死亡.其余病例前列腺特异抗原<0.2μL.结论 腹腔镜前列腺癌根治术治疗局限性前列腺癌是安全、有效的.术后控尿功能主要与术中前列腺尖部、耻骨前列腺韧带和神经血管束的处理及手术经验相关.     

Nerve sparing endoscopic extraperitoneal radical prostatectomy--effect of puboprostatic ligament preservation on early continence and positive margins

INTRODUCTION: A technical modification of nerve sparing endoscopic extraperitoneal radical prostatectomy (nsEERPE) with preservation of the puboprostatic ligaments is presented and compared to a previous technique. MATERIALS AND METHODS: nsEERPE was performed in 100 men with clinically localized adenocarcinoma of the prostate from March 2004 through February 2005. Patients were divided into two groups: Group A included patients in whom a standard nsEERPE was performed (n=50), and group B included patients in whom a puboprostatic ligament sparing nsEERPE was performed (n=50). The postoperative follow-up was 2 weeks and 3 months evaluating preliminary effects on early continence and positive margins. RESULTS: The early return to continence at 2 weeks postoperatively was achieved by 6 patients (12%) in group A, and 12 patients (24%) in group B. Three months after the procedure 24 (48%) and 38 (76%) patients were continent, in groups A and B respectively. Clinical outcome (early continence) was significantly better for Group B patients, at 2 weeks (chi-square test, p=0.0019) and at 3 months (chi-square test, p=0.0347) following surgery. No cases of complete or severe incontinence (more than 5 pads/day) were observed at 3 months after surgery, in either groups. Groups A and B did not exhibit significant differences regarding their histological status. In group A, positive margins were detected in 6.5% and 26.3% of patients with pT2 and pT3, respectively. In group B, positive margins were found in 3.2% and 15.8% of patients with pT2 and pT3, respectively CONCLUSION: We propose the use of puboprostatic ligament-sparing nsEERPE as an intriguing method to ascertain recuperation of early continence after nerve sparing procedures, without hindering the final oncological outcome.     

低温下筋膜内前列腺癌根治术对早期控尿及勃起功能的影响

目的：探讨低温下筋膜内前列腺癌根治术对早期控尿及勃起功能的影响。方法：选择穿刺活检证实的早期前列腺癌患者21例,其中有性生活者17例,在25℃生理盐水局部低温处理下行筋膜内前列腺癌根治术。结果：21例手术均顺利完成,出血量2001100（300±95）ml,平均留置尿管8（6～14）天。术后随访6个月,完全控尿18例（85％）;17例术前有性生活的患者中,术后6个月可完成性生活者13例（76％）。结论：局部低温的应用减轻了前列腺癌根治术的创伤性炎症后遗反应;低温下筋膜内前列腺癌根治术对早期控尿与勃起功能的恢复有益。     

Prostate shape, external striated urethral sphincter and radical prostatectomy: the apical dissection

In an anatomical study of 64 gross specimens the external striated urethral sphincter was reconfirmed to extend as a single unit from the proximal penile urethra to the bladder base. The configuration of the external striated urethral sphincter was variable and was related to the shape of the apical prostate. Two basic prostatic shapes were recognized, distinguished by the presence or absence of an anterior apical notch. Whether a notch existed depended upon the degree of lateral lobe development and the position of its anterior commissure. In radical prostatectomy knowledge of the variation in the shape of the prostatic apex can help the surgeon to achieve optimal urethral transection with maximal preservation of the external striated urethral sphincter and other tissues of the continence mechanism.