Functional and Clinicopathologic Outcomes Using a Modified Vescica Ileale Padovana Technique

INTRODUCTION

Radical cystectomy remains the gold standard for management of muscle-invasive bladder cancer [1, 2]. Estimates using data from the Surveillance, Epidemiology, and End Results (SEER) database predict that approximately 18,600 new muscle-invasive bladder cancer cases will be diagnosed in 2014. Analysis of this SEER data reveals that 42% of these patients with muscle-invasive disease ultimately undergo cystectomy [3], necessitating the surgical diversion of urine in the form of an incontinent ileal conduit, a continent orthotopic pouch that empties via urethra, or a catheterizable non-orthotopic cutaneous stoma [4]. Orthotopic neobladders allow voiding through the native urethra and can potentially eliminate the need for stoma appliances or catheters without compromising cancer control [5]. Neobladders created from ileum have been found to be more compliant than those created with large bowel [6], and by detubularizing and refolding into a spherical shape, low pressure filling at physiologic capacity can best be achieved [6]. Specifically, spherical configurations maximize volume for any given surface area, thus decreasing the length of bowel needed for harvest and minimizing the opportunity for electrolyte exchange across the neobladder wall [7]. The specific folding method used varies greatly among institutions and little evidence exists that definitively favors one technique versus another.

Two techniques routinely used at our institution for neobladder creation are the Studer and the vescica ileale Padovana (VIP) techniques. A distinction of the VIP technique is its complete use of bowel segment in the spherical component of the neobladder [8] whereas the Studer neobladder involves the creation of an afferent limb that does not contribute to bladder volume [9]. There are many published studies available that report functional and oncologic outcomes for the Studer neobladder [10–13], but fewer large studies exist that offer data on such outcomes specifically following VIP neobladder creation [8, 14].

Modified creation of the Vescica ileale Padovana (VIP) neobladder has been performed at our institution over a 15-year period. We sought to evaluate the clinicopathologic and functional outcomes of this technique.

METHODS

RESULTS

One hundred and sixty patients were identified as undergoing VIP neobladder creation during the study period. Patient characteristics are shown in Table 1. The majority of patients underwent radical cystectomy for muscle invasive bladder cancer (64%). Forty-seven percent of patients had ≤pT1 disease on cystectomy pathology, and 30% of patients were pT3-4.

With regard to early and late complications (Table 2), 16 patients (10%) developed a Clavien grade 3-4 complication within 30 days of surgery, and no patients died within 30 days of surgery (Clavien grade 5). Of the 13 women undergoing modified VIP replacement, all had attempted sparing of the anterior vaginal wall and none were clinically T3 or higher at the time of surgery. Two patients had small inadvertent vaginotomies that were closed primarily. There were no vesicovaginal fistulas. Seven patients (4%) developed ureteral stricture, four of which occurred within one year of surgery. All strictures were managed successfully: five with ureteral reimplantation, one with an ileal ureter, and one with temporary stenting. Three patients (2%) developed a bladder neck contracture, two of which occurred within one year of surgery. Two contractures were managed by incision, one was managed with sequential dilation, and only one patient required intermittent catheterization following contracture. One patient developed a late urethral stricture (1%), which was managed with conversion to ileal conduit.

Median follow-up of patients was 73 months. Two patients (1%) experienced urethral recurrence. Overall survival is shown in Fig. 2, with median survival not reached. Two-year overall survival was 84.2% and five-year overall survival was 72.6% . Fifteen patients died within one year of surgery, ten of which had progression of disease and five were disease free at last follow-up.

Functional outcomes are shown in Table 3, representing only those patients with twelve-month follow-up (n = 107). Incidence of mild hydronephrosis decreased dramatically from the three-week to twelve-month appointments and no patients had moderate or severe hydronephrosis at either point in time. Seven patients (7%) were catheterization dependent at 12 months due to urinary retention, and an additional nine patients opted to catheterize daily in addition to spontaneous voiding in order to ensure complete emptying.

DISCUSSION

The technique for VIP neobladder creation was first described in 1990, with its authors advocating orthotopic bladder replacement following cystectomy as “the ideal solution to enhance the quality of the patient’s life.” Their new surgical technique promised improved rates in both daytime and nighttime continence [8]. In performing this study we were able to investigate the validity of this claim as well as explore other clinicopathologic outcomes resulting from this particular method of bladder substitution.

In our modified technique for the neobladder there are several distinct advantages. The near pure spherical configuration maximizes the ratio of bladder volume to amount of bowel utilized [16]. Offset opening of the bowel wall results in a wider, well-vascularized bowel segment to use for ureteral reimplantation. This allows for a minimally mobilized ureter and reimplantation distant from any suture lines, which contributes to the very low ureteral stricture rate. This placement also ensures that when ureteral strictures do occur, they are easily accessible surgically. Stricture rates in the literature are reported to be as low as 2.7% following refluxing anastomosis, and we found our own rates to be comparable [12, 17]. Offset opening also facilitates ease in reaching the native urethra (even in obese individuals) when creating the neourethra, a dependent funnel that promotes better bladder emptying. And finally, this modified technique results in intervening mesentery that avoids posterior overlapping suture lines. This mitigates risk of fistulae formation potentially caused by ongoing urinary drainage into areas of injury [11, 18–20] should tumor anatomy necessitate removal of the anterior vaginal wall or if inadvertent entry is unavoidable. In our own experience, with two unplanned vaginotomies, neither resulted in vesicovaginal fistula.

Our rate of reported postoperative complications, while significant, was at the low end of ranges reported previously. Given the extent of disease and scope of this procedure, expected morbidity following radical cystectomy is high, ranging from 20 to 57% during the first 30 days postoperatively as reported in a review by Richards et al. [21] and rising to 64% of patients within the first 90 days as reported by Shabsigh et al. [22]. In the previously discussed studies, as well as within our own cohort, the predominant percentage of complications was minor in nature. Fortunately, despite these high complication rates mortality remains relatively low, with 1.5% deaths in the first 30 days as reported by Shabsigh et al. [22] and no perioperative deaths reported in our own series.

When comparing on the basis of quality of life, available literature does not definitively support the implementation of one type of reconstruction over another [23, 24]. With a funneled bladder outlet, there is some reported concern for kinking requiring catheterization to void [12]. However, the anatomic placement of the neobladder reservoir helps to avoid this concern for retention, with only seven patients requiring intermittent catheterization to void at one year. This is similar to that seen in other large cohorts, for example Studer et al. report 4.6% use of indwelling catheter or intermittent catheterization in their cohort [12]. Continence varies slightly between published cohorts based on the definition used. However, despite this, our rates compare favorably to those seen previously [10, 14, 16] with daytime continence (no leakage or minor leakage) at 96% and nighttime continence (no leak or occasional low leakage) of 70% . Hautmann et al. report ranges of 88–95% daytime and 66–93% nighttime in their review of the literature [16]. Studer et al. too found with their technique that 12 months after surgery, 92% of neobladder patients considered themselves continent (completely dry or minimal loss of a few drops of urine, 1-2 times per month) during the day and 79% reported continence at night [12, 25]. Although there are a number of factors including patient age as well as attempted nerve sparing and native sphincter preservation [16] that contribute to continence, the ability to achieve low pressure filling at physiologic capacity is a major contributor to both daytime and nighttime continence. This highlights the importance of the nearly spheroidal configuration of this neobladder technique.

Results of this study reveal favorable oncologic outcomes as compared to other published orthotopic diversions. Our five-year overall survival was 72.6% , as compared to the series published by Stein et al. that reported 66% 5-year overall survival in their cohort of 1,054 patients undergoing cystectomy [1]. Madersbacher et al. too reported a 5-year overall survival of 59% in 507 patients undergoing cystectomy for node negative, metastasis negative transitional cell carcinoma [2, 6]. Because neobladder creation necessitates sparing the urethra, it carries with it an inherent risk of urethral recurrence not universally present in other forms of continent diversion where urethrectomy is possible. Despite mitigating this risk with intraoperative urethral frozen section analysis, a small percentage of recurrences are expected. Our personal experience yielded two urethral recurrences (1%), which correlates well with a meta-analysis by Gakis et al. that reports urethral recurrence rates with orthotopic diversion of 1.1–2.5% [6]. These favorable results likely relate to patient selection, whereby patients chosen for neobladder creation are often lower clinical stage with less muscle invasive disease. This is evidenced by the fact that nearly half of our patients had ≤pT1 disease on cystectomy pathology and only ten patients were pT4.

We recognize that there are limitations in this study. Because the study is purely descriptive, without comparison or randomization, there is potential for bias whereby physician selection of patients with a potentially higher preoperative functional status and more favorable tumor features might bias the study results. Indeed our cohort has a predominance of younger patients with low stage disease, however this reflects the reality of patient selection for orthotopic bladder replacement – an option typically reserved by for patients meeting strict criteria that would indicate success. A lack of validated pre- and postoperative quality of life data makes comparison to other studies more challenging. Previously, generic questionnaires set strict standards for a definition of ‘continence’, particularly nighttime continence, that is potentially unreasonable to expect in the post-cystectomy setting. Although disease specific quality of life questionnaires have since been validated [27, 28] to address concerns that are more specific to this population such as need for catheterization, difficulties with stoma care or stoma appliances, and the distinction between daytime and nighttime continence, [23] many institutions (including ours) have only recently begun to incorporate these into practice. Perhaps the most challenging limitation is the retrospective nature of this study and its incomplete data set. Nevertheless, we believe that our cohort represents one of the largest experiences in the literature to assess functional, complication, and clinicopathologic outcomes in this unique population.

CONCLUSION

Modified VIP neobladder technique achieves favorable functional, survival, and recurrence outcomes similar to other published orthotopic continent diversions. Its near spheroidal shape optimizes the bowel surface area to volume ratio, lowering internal pressure and allowing for improved continence at physiologic filling capacity. Its offset bowel opening helps prevent unnecessary stretch to the native urethra, even in large individuals. The widened uretero-enteric anastomosis site distant from bowel suture lines contributes to decreased stricture rates and its placement on the dome of the neobladder facilitates endoscopic access should strictures occur. Finally, lack of posterior overlapping suture lines also mitigates the risk of fistulae formation in females should anterior vaginal wall excision or entry be unavoidable.