Posterior musculofascial plate reconstruction promotes early restoration of continence and prevents severe incontinence in patients undergoing laparoscopic radical prostatectomy

Authors


Takeshi Sano M.D., Department of Urology, Otsu Municipal Hospital, 2-9-9 Motomiya, Otsu-shi, Shiga 520-0804, Japan. Email: sanotake@kuhp.kyoto-u.ac.jp

Abstract

The objective of the present study was to assess the efficacy of posterior reconstruction of Denonvilliers' musculofascial plate for restoring urinary continence after laparoscopic radical prostatectomy. A total of 48 consecutive patients who underwent laparoscopic radical prostatectomy were retrospectively reviewed. Of them, 23 underwent laparoscopic radical prostatectomy without posterior reconstruction of Denonvilliers' musculofascial plate (group 1) and 25 underwent laparoscopic radical prostatectomy with posterior reconstruction of Denonvilliers' musculofascial plate (group 2). Patients' demographics were analyzed and continence rates between the two groups at 1, 3, 6 and 12 months after surgery were compared. Patients in group 2 had significantly larger prostates than in group 1. There were no significant differences between the two groups in terms of the other patient characteristics. The urinary continence rates were significantly higher in group 2 than in group 1 at 1, 3 and 12 months after surgery, and the rates of severe incontinence were significantly lower in group 2 at all time-points considered. These findings suggest that posterior reconstruction of Denonvilliers' musculofascial plate helps in restoring early continence and decreasing severe incontinence in patients undergoing laparoscopic radical prostatectomy.

Abbreviations & Acronyms
BMI =

body mass index

LRP =

laparoscopic radical prostatectomy

MUL =

membranous urethral length

PRDMP =

posterior reconstruction of Denonvilliers' musculofascial plate

PSA =

prostate-specific antigen

RP =

radical prostatectomy

Introduction

Urinary incontinence caused by RP for prostate cancer is a major disadvantage of the surgical treatment. At 1 year after both open RP and LRP, urinary continence rates are high, ranging from 88% to 97%.1–5 Early continence recovery rates, however, are still insufficient. Recently, several technical modifications have been proposed to promote an earlier return of continence, including sparing of the bladder neck,6,7 preservation of the puboprostatic ligament8 and anterior reconstruction of the puboprostatic collar.9 PRDMP is one of the most common procedures. Although the technique was originally proposed by Rocco et al. to acquire an early recovery of urinary continence in open retropubic RP,10 similar results have been reported in LRP and robotic prostatectomy.11,12 In Japan, however, no study has examined the efficacy of this procedure. In the present study, we investigated whether an adapted version of PRDMP shortened continence time after LRP.

Methods

We carried out LRP without PRDMP for 23 consecutive patients between January and August 2007 (group 1), and LRP with PRDMP for 25 consecutive patients between August 2007 and September 2008 (group 2). A single surgeon, who had carried out more than 100 LRP operations, carried out the surgery in accordance with the technique developed at the University of Leipzig and reported by Stolzenburg et al.13,14 We carried out PRDMP according to the original procedure introduced by Rocco et al. (Fig. 1a–f).10 After the prostate was removed, the transected musculofascial plate posterior to the urethra (posterior median raphe) was fixed to the cranial residuum of Denonvilliers' fascia using two 2-0 polyglactin sutures on a CT-2 needle. Then, these two sutures were applied 1–2 cm cranial and dorsal to the bladder neck. After PRDMP, urethrovesical anastomosis was carried out using the technique proposed by Shichiri et al.15 The primary end-points of the study were the comparison of continence rates between the two groups at 1, 3, 6 and 12 months after surgery. Urinary continence was defined as no pad use or 0–1 security pad per day, and severe incontinence was defined as the use of three or more pads per day. Clinical demographics of the patients were analyzed using Student's t-test and the χ2-test. Comparison of continence rate within each time-point between groups was carried out by Fisher's exact probability test of the χ2-test. Statistical significance was considered to be P < 0.05. All statistical analyses were carried out with JMP 6.0.2 (SAS Institute, Cary, NC, USA).

Figure 1.

Intraoperative photographs. (a,b) The first 2-0 suture is placed on the right side of the posterior median raphe and the cranial residuum of Denonvilliers' fascia. (c) The suture is tightened and additionally placed 1–2 cm cranial and dorsal to the bladder neck. (d) On tying down the suture, the bladder neck descends into the urethral stump. (e,f) The second 2-0 suture is placed on the left side, using the same procedure.

Results

The two groups were similar in terms of age, BMI, preoperative PSA, pathological stage, operation time and blood loss (including through urine). Patients in group 2 had significantly larger prostates than in group 1 (Table 1). The urinary continence rates at 1, 3, 6 and 12 months after surgery were 0%, 30.4%, 52.2% and 56.5% (group 1), and 44%, 60%, 72% and 88% (group 2), respectively. The urinary continence rates of group 2 were significantly higher than those of group 1 at 1, 3 and 12 months after surgery (Fig. 2). Severe incontinence rates were significantly lower in group 2 at all examined time-points (Fig. 3). Unilateral nerve-sparing procedures were carried out in one patient of group 1 and in five patients of group 2. Three of the patients of group 2 regained continence within 3 months. We found no significant correlation between nerve sparing and recovery of urinary continence, as determined using Fisher's exact probability test (data not shown).

Table 1.  Baseline patient characteristics and perioperative outcomes
 LRP without PRDMP (Group 1)LRP with PRDMP (Group 2)P-value
  1. Evaluated by unpaired Student's t-test; *evaluated by χ2-test.

No. patients2325 
Age (years), mean ± SD70.8 ± 6.467.2 ± 8.30.098
BMI (kg/m2), mean ± SD23.6 ± 2.323.3 ± 2.60.7
PSA (ng/mL), mean ± SD12.3 ± 12.412.1 ± 10.10.95
Prostate weight (g), mean ± SD35.5 ± 9.145.5 ± 19.20.036
Pathological stage (%)   
 T252.2600.48*
 T347.836
 T404
Operative time (min), mean ± SD211 ± 40.6231 ± 47.70.15
Blood loss (mL), mean ± SD382 ± 299515 ± 4450.23
Figure 2.

Continence after catheter removal. Rates of continence in group 2 (LRP with PRDMP) were significantly higher than in group 1 (LRP without PRDMP) at 1, 3 and 12 months after LRP (Fisher's exact probability test, *P < 0.05). Urinary continence was defined as no pad use or 0–1 security pad per day. inline image, LRP without PRDMP (group 1); inline image, LRP with PRDMP (group 2).

Figure 3.

Rates of severe incontinence after catheter removal. Rates of severe incontinence in group 2 were significantly lower than in group 1 at 1, 3, 6 and 12 months after surgery (Fisher's exact probability test, *P < 0.05). Severe incontinence was defined as the use of three or more pads per day. inline image, LRP without PRDMP (group 1); inline image, LRP with PRDMP (group 2).

Discussion

Musculofascial plate reconstruction was introduced by Rocco et al. with the aim of reducing the time required to regain continence. According to the authors, PRDMP promotes early continence recovery by restoring both anatomical and functional urethral length, and reconstructing the posterior support of the longitudinal urethrovesical axis.10 Nguyen et al. assessed the MUL during LRP or robotic RP by transrectal ultrasonography, and found that the MUL is decreased by an average of 3.6 mm during prostate ablation. In contrast, PRDMP restores MUL by an average of 2.0 mm.12 In line with these studies, Woo et al. showed that PRDMP reduces the time required to achieve continence, the median time to continence of patients undergoing robotic RP with or without PRDMP being 90 and 150 days, respectively.16

Although compelling evidence has shown the advantages of the reconstruction, some less optimistic results have been recently reported. Menon et al. carried out a randomized controlled trial that compared one group undergoing reconstruction with another group undergoing the standard procedure, and found no significant differences in continence rates between the two groups at 1, 2, 7 and 30 days after catheter removal.17 All of the enrolled patients underwent meticulous nerve-sparing operations after experiencing extremely high-volume robotic RP, which might have contributed to early continence recovery (the continence rate was 74% in the standard group at 30 days after catheter removal).18 We speculate that their results might not be generally applicable to other institutions. Joshi et al. also reported that reconstruction provides no benefit for urinary continence 3 and 6 months after surgery.19 They suggested that robotic RP lessens urinary incontinence during the early postoperative period, because the magnified stereoscopic view and more maneuverable instruments might allow better preservation of the sphincteric/supporting musculature.

The present results suggest that PRDMP is beneficial for early urinary continence recovery after standard LRP in a community hospital without intensive fascia preservation. To the best of our knowledge, this is the first report showing the efficacy of musculofascial plate reconstruction in preventing severe postoperative incontinence. In the present study, reconstruction significantly decreased severe incontinence at all analyzed time-points. Remarkably, none of the patients in group 2 had severe incontinence at 12 months after catheter removal.

The present study had several limitations. First, the outcomes of the present retrospective non-randomized study might have been biased by patient selection. Patients with PRDMP (group 2) had slightly greater prostate weight, which might affect the outcomes. However, there have been no reports that larger prostate glands are associated with decreased risk of incontinence after prostatectomy. Furthermore, we carried out unilateral nerve sparing for more patients in group 2 than in group 1. We, however, carried out unilateral extrafascial nerve sparing for a small number of patients, which would not affect the recovery of urinary continence. Some reports have suggested that even bilateral extrafascial nerve sparing does not improve urinary continence.20,21 Second, the learning curve of a single surgeon might have affected the continence outcome. However, we regard this limitation as minimal, because our team had carried out more than 100 LRP and had reached a technical plateau. Third, the former 23 patients (who did not undergo reconstruction) had continence rates that were lower than those reported in the literature. We regarded any involuntary urine loss as incontinence, and this strict definition might have accounted for the difference in the outcomes.

In conclusion, the present study showed that musculofascial plate reconstruction is a useful technique to promote early restoration of continence and prevent severe incontinence after LRP. In Japan, further randomized controlled trials are required to confirm that PRDMP – when carried out at the time of LRP – shortens continence recovery and prevents severe incontinence.

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