Urinary diversion and reconstruction following cystectomy

INTRODUCTION — Removal of the bladder (cystectomy) is required to treat certain malignant (eg, bladder, colorectal cancer) or nonmalignant conditions (eg, congenital anomaly, trauma, neurologic disorders) [1-3]. After cystectomy, urine needs to be redirected with a urinary diversion and reconstruction procedure.

Ureterosigmoidostomy, which relied upon the anal sphincter for continence, was the first widely used surgical technique of urinary diversion. Its usefulness, however, was limited by deterioration of renal function over time, metabolic complications, and the development of secondary sigmoid colon cancers. (See 'Complications' below.)

Newer urinary diversion techniques, including continent cutaneous diversions and internal reservoirs connected to the native urethra, have improved quality of life and patient acceptance by permitting volitional voiding. Earlier patient acceptance of radical cystectomy in the natural history of bladder cancer may ultimately improve the outcome of bladder cancer treatment [4].

This topic discusses the three reconstructive options most widely used after cystectomy, ileal conduit, continent cutaneous diversion, and orthotopic neobladder. The management of bladder cancer is discussed separately, as are the techniques of radical cystectomy:

●(See "Overview of the initial approach and management of urothelial bladder cancer".)

●(See "Radical cystectomy".)

RECONSTRUCTIVE OPTIONS

Conduits and reservoirs — In urinary diversion, a conduit or a continent reservoir is required to replace the bladder and provide an internal reservoir or facilitate transit of urine to an external appliance. The ideal characteristics of a urinary reservoir are listed in the following table (table 1).

Urinary conduits and reservoirs are typically constructed from an isolated segment of bowel. In theory, any segment of bowel can be used to form a urinary diversion. However, there are metabolic consequences to using each bowel segment, determined by its absorptive function [5-21]. While most metabolic abnormalities are clinically subtle, they may assume significance in patients with renal insufficiency and in adolescents and young adults who will be subjected to the metabolic abnormalities for a prolonged period. (See 'Nutritional and metabolic abnormalities' below.)

The most commonly used bowel segments in urinary diversions include the distal ileum and/or cecum and the ascending or sigmoid colon; these sites are associated with the fewest metabolic consequences.

The primary indications for the use of various bowel segments and the associated metabolic consequences and symptomatology are shown in the following table (table 2) [19,22-25]. In addition, the length and location of the segment used can affect the patient's postoperative bowel function.

Reconstructive techniques — Urinary diversion procedures following cystectomy fall into two general categories: incontinent diversions and continent reconstructions.

●Incontinent urine diversion simply directs urine from the ureters through a segment of isolated bowel to the surface of the abdominal wall via a cutaneous stoma. There, urine drains continuously and is collected by an external appliance adhered to the skin surface [26]. The most common type of incontinent urinary diversion is an ileal conduit. (See 'Ileal conduits' below.)

●By contrast, continent reservoirs collect and store urine internally and empty stored urine intermittently by catheterization via a cutaneous stoma or volitional voiding. The patient is thereby freed from the need for an external appliance.

•A continent cutaneous diversion creates a low-pressure reservoir from a bowel segment and connects it to the skin via a continent channel. The patient empties the urine by self-catheterizing the continent channel. (See 'Continent cutaneous diversions' below.)

•By contrast, an orthotopic neobladder connects the bowel segment to the intact urethra. This procedure allows the patient to void volitionally through the urethra, restoring a more natural voiding pattern. (See 'Orthotopic neobladders' below.)

The process of selecting a particular urinary diversion option is complex and will be presented after each procedure has been described in detail. Factors that should be considered include oncologic (cancer stage and location, urethral margin), surgical (available bowel segment, pelvic radiation, surgeon experience), and patient-related factors (comorbidity, lifestyle, quality of life expectations) (table 3). (See 'Procedural selection' below.)

ILEAL CONDUITS — Ileal conduits were the gold standard for urinary reconstruction before the advent of continent diversions [27]. Due to the relative ease of their formation and the shorter operative time, ileal conduits are often used in patients with significant medical comorbidities to minimize postoperative complications and the risk of reoperation. Ileal conduits remain the procedures of choice for many patients, especially those with a shorter life expectancy and those who cannot complete the necessary rehabilitation process to learn how to manage a continent diversion.

Techniques of ileal conduit — An ileal conduit serves as a method for urine to drain to the exterior. A segment of ileum is selected; the terminal 10 to 15 cm of ileum at the ileocecal junction is typically preserved to maintain adequate absorption of bile salts, vitamin B12, and fat-soluble vitamins. The isolated segment of ileum is exteriorized through the abdominal wall as a stoma, around which an appliance is secured to collect urine. The presence of the stoma and appliance can affect a patient's body image.

Patients with obesity may require a loop-type (Turnbull) stoma because a short bowel mesentery and thick abdominal wall may prevent the creation of an end-on stoma without undue tension [28].

Outcomes of ileal conduit — Ileal conduits have been used for decades since the first report in 1950 by Bricker [26], and therefore detailed information is available regarding the incidence of complications [27,29,30]. Despite the fact that ileal conduits are often performed for patients with significant medical comorbidities, the complication rates are comparable to those of continent diversions performed for generally healthier patients (table 4).

The outcomes of ileal conduits are best illustrated by a series of 412 patients followed for a median of 98 months; the frequency of complications ranged from 45 percent at five years to 94 percent at greater than 15 years [27]. The overall rate of complications associated with conduits is similar for ileum and colon segments among properly selected patients [27,31,32]. The most frequent complications are renal insufficiency, stomal problems, bowel problems, urinary tract infections, ureteral obstruction, and urinary calculi (in 27, 24, 24, 24, 14, and 9 percent, respectively) [27].

Parastomal hernias are another frequent complication after ileal conduit diversion. The incidence varies widely from 12 to 48 percent, depending on the definition used, the length of follow-up, and whether the diagnosis is made clinically or radiographically [30,33,34]. Factors that increase the risk for developing a parastomal hernia include female sex, obesity, low preoperative albumin, and prior abdominal surgery [34]. Approximately 40 percent of patients with clinically apparent parastomal hernias report symptoms, such as difficulties with the ostomy appliance (poor fit, leakage), pain, and incarceration. As subsequent surgical repair of a parastomal hernia has potential morbidity and high rates of hernia recurrence [35], prophylactic mesh placement at the time of ileal conduit creation is being evaluated in several randomized controlled trials and may prove to be a preferred approach to patients at increased risk for parastomal hernia development [35-38]. (See "Parastomal hernia" and "Prophylactic mesh for ventral incisional hernia prevention".)

CONTINENT CUTANEOUS DIVERSIONS — All continent cutaneous reservoirs rely upon a low-pressure pouch constructed of various detubularized bowel segments and a functional mechanism that connects the reservoir to the skin designed to prevent involuntary urine flow. The most obvious advantage of this type of diversion is the ability to avoid continuous urine drainage with the need for an external appliance. These continent cutaneous diversions require lifelong intermittent clean self-catheterization through the stoma both to empty the reservoir and to irrigate mucous.

Patient education, motivation, and manual dexterity are required to manage the stoma and perform the necessary self-catheterization successfully [29]. Although continent cutaneous diversions have been largely supplanted by the orthotopic neobladder, this procedure is used when avoidance of an external appliance is desired but the urethra or bladder neck is nonfunctional or involved by tumor.

Techniques of continent cutaneous diversions — Many technical variations exist based upon the type of valve mechanism constructed and the segment of intestine utilized. Examples include the Kock, Indiana, and Miami pouches [39-41]. The Kock pouch has fallen out of favor due to the technical complexity of constructing the continent nipple valve and a high rate of complications often requiring reoperation. The Indiana and Miami pouches rely on a tapered ileal segment and plicated ileocecal valve to maintain continence.

Using the in situ appendix as the continence mechanism and catheterizable limb has improved outcomes and lowered major complication rates [42], and it is a pouch design that can be performed in previously radiated patients [43,44].

Another modification uses a tubularized segment of terminal ileum as a ureteral substitute to allow a more proximal ureteroenteric anastomosis and avoid the use of distal ureteral segments that may have been within the fields of radiation. The length of the ileal limb can be tailored to achieve a tension-free anastomosis with the proximal left ureter in the retroperitoneum [45].

Outcomes of continent cutaneous diversions — The majority of studies have demonstrated the safety and functional benefits of continent cutaneous diversions, with daytime and nighttime continence rates reported in the range of 90 to 98 percent [46,47].

However, complication rates can be significant. As an example, among 112 patients receiving a modified Indiana pouch at a single institution, 90 percent experienced one or more complications at 41 months [48]. Incontinence (any leakage) was the most common complication (28 percent) [48]. The reported rates of incontinence vary significantly depending upon the criteria used to define incontinence and the length of follow-up [29,32,48-51].

Incontinence with a continent cutaneous diversion can be due to uninhibited pouch contractions, poor pouch compliance, or an incompetent continence mechanism. Pouch urodynamics are helpful in categorizing the cause of the incontinence.

●In patients with a poorly compliant, high-pressure reservoir, an initial trial of anticholinergics is the preferred approach. Refractory cases usually benefit from augmenting the reservoir with a patch of bowel to decrease pressure and increase capacity.

●Incompetent continence mechanisms usually require open revision, although minimally invasive approaches, such as injecting bulking agents, are often helpful for mild incontinence.

Other frequent and troublesome long-term complications involve the efferent limb and catheterizable stoma. The reported rate of stomal stenosis and difficulty in catheterizing the stoma is 4 to 15 percent [48,51]. Additional problems include stone formation within the pouch and urinary tract infections, which are observed in up to 20 percent of patients. Twenty-one percent required a reoperation, mostly for stomal stenosis [48].

ORTHOTOPIC NEOBLADDERS — Orthotopic neobladders are internal reservoirs connected to the native urethra that rely upon the external striated sphincter and a high-capacity, low-pressure reservoir for continence. Because this approach facilitates the restoration of normal self-image by approximating normal voiding, orthotopic neobladders have become the procedure of choice for many patients requiring reconstruction following cystectomy for bladder cancer [52].

Techniques of orthotopic neobladders — Neobladder reservoirs are constructed from a segment of detubularized intestine (usually ileum) and anastomosed to the native urethra.

Some neobladders (eg, the hemi-Kock) incorporate an antireflux mechanism to limit backflow of urine from the reservoir to the upper urinary tracts. Although this mechanism mimics the normal antireflux apparatus of the native bladder, its requirement is controversial, and most urologists do not perform this mechanism:

●Proponents cite the detrimental upper tract changes seen in patients who are followed for 10 years or longer after ileal conduits or ureterosigmoidostomy, both of which are associated with free reflux of infected urine [53-56].

●Opponents question the need for specific antireflux maneuvers for the following reasons:

•Long-term complications of reflux with orthotopic neobladders have been predominantly seen in patients who have high-pressure reservoirs. Contemporary neobladder designs ensure low filling pressures.

•Voiding pressures within orthotopic neobladders are generated via the Valsalva maneuver and exerted to all of the intra-abdominal contents, including the ureters and renal pelvis. This equal pressure distribution minimizes reflux during voiding. In addition, some neobladder designs (eg, the Studer reservoir) utilize a long isoperistaltic proximal limb, which provides resistance to retrograde flow, thereby providing additional antireflux protection [57,58]. Long-term follow-up of patients with neobladders that do not incorporate an antireflux design have confirmed that reflux-related complications are rare.

•Ureteral anastomoses that are designed to prevent reflux may lead to a greater risk of complications (eg, ureteroenteric stricture, ischemic fibrosis of the antireflux valve, stone formation from staples used to construct the valve system), which contribute substantially to morbidities, including impaired renal function [59,60].

Orthotopic neobladders were initially limited to men. In women, urethra-sparing orthotopic substitution was thought to be associated with an increased risk of local recurrence and voiding dysfunction. With improved understanding of the female rhabdoid sphincteric (continence) mechanism, however, this approach has become technically feasible and oncologically safe in selected women as well [61]. The selection criteria for orthotopic neobladders are discussed below. (See 'General approach' below.)

Outcomes of orthotopic neobladders — The functional goals of an orthotopic neobladder are to maintain continence during both the day and night and to allow consistent emptying of the neobladder without the need for intermittent catheterization.

Continence after an orthotopic urinary diversion is dependent upon an intact external urinary sphincter and pelvic floor, adequate functional urethral length, a high-capacity/low-pressure reservoir, and the age of the patient. Attention to neobladder design, careful surgical technique, appropriate patient selection, and patient education all contribute to optimizing functional results [29,62].

Urinary continence — Generally speaking, continence continues to improve over the first year after surgery as the capacity and compliance of the neobladder increase [63,64]. The continence rate, however, can vary by day versus night, men versus women, and young versus old:

●Daytime continence with orthotopic diversions is better and typically precedes nighttime urinary control by 6 to 12 months.

Daytime continence rates after orthotopic diversions generally exceed 85 to 90 percent at centers of excellence but have been reported to range from 47 to 100 percent depending on the definition of continence and the length of follow-up [56,65-69].

As with daytime control, nocturnal continence is achieved gradually over the first year once the capacity and compliance of the continent diversion increase. Satisfactory nighttime continence rates at one year range between 71 to 80 percent at high-volume centers [65,70,71]. However, many patients still require nighttime protection, as there is no communication between the contractions in the reservoir and the urinary sphincter, due to loss of afferent input from the detrusor to the central nervous system, and no corresponding increase in urethra resistance during filling. Nerve-sparing surgery, when appropriate, is associated with optimal diurnal continence.

●In several large series comprised predominantly of men, daytime and nighttime continence rates ranged from 87 to 100 percent and 70 to 95 percent, respectively (table 5) [56]. In women, daytime continence rates were also very high (75 to 93 percent) at average follow-up durations of 20 to 33 months; nighttime rates were similar to those of men at 72 to 84 percent (table 6) [72-76].

●Continence rates in individuals over age 70 are lower than those in younger patients.

Voiding dysfunction — A meta-analysis of more than 2000 patients showed a 4 to 25 percent rate of intermittent self-catheterization after neobladder diversion for incomplete emptying [62]. Reported causes of incomplete emptying include urethral angulation, elongation of the neobladder neck, the neobladder neck being in a nondependent portion of pouch, an oversized floppy neobladder, a preserved but dysfunctional native bladder neck, denervated proximal urethra, inadequate pelvic floor relaxation during voiding, and ineffective Valsalva straining [77].

Inadequate emptying of the neobladder in men is uncommon. In a single-institution series of 655 men, inadequate emptying (defined as a residual volume >100 mL) was observed in 75 cases (11.5 percent) [77]. In 52 patients, this was due to mechanical obstruction, most commonly either benign strictures of the neovesicourethral anastomosis or local tumor recurrence; in 38 of these cases bladder emptying was restored with a local urological procedure, while 14 required some form of long-term catheterization. In the 23 cases without a mechanical obstruction, failure of bladder emptying was dysfunctional, and intermittent or indwelling catheterization was required.

Women have a higher risk of requiring intermittent catheterization after orthotopic neobladders, ranging from 11 to 70 percent. The increased need for intermittent catheterization (due to urinary retention) in women is thought to be due in part to a posterior prolapse of the neobladder during Valsalva voiding. Urinary retention associated with female neobladders may be minimized if meticulous surgical technique is used to preserve the autonomous nerve fibers to the remnant urethra and omental flaps are used to provide additional support [78].

Quality of life — Comparisons between orthotopic diversion and incontinent cutaneous diversion are limited by inherent selection bias and the lack of validated instruments to measure bladder-cancer-specific health-related quality of life (QOL) [79]. For example, patients undergoing continent diversion report better baseline QOL levels for physical, urinary, and sexual function compared with patients receiving ileal conduit diversions [80].

Although some reports have noted improvements in various aspects of QOL (eg, body image) using newer reconstructive techniques such as orthotopic neobladder, few formal studies have documented an improvement in overall QOL [81-85]. A systematic overview of 15 published studies (only one prospective, none randomized) examining health-related QOL after radical cystectomy and urinary diversion for bladder cancer found insufficient data to conclude that any one form of urinary diversion was associated with a better QOL [86].

Ultimately, diversion type may not be the defining factor in QOL after cystectomy. Instead, other patient, social, or process factors may control long-term outcomes. While orthotopic diversion may provide several QOL benefits for selected patients, psychological adaptation to urinary diversion appears to result in similar QOL states for patients one year after surgery.

Critically, regardless of the selected urinary diversion type, there is excellent preservation of QOL following cystectomy across multiple domains [80]. Recovery of QOL occurs as early as three months after cystectomy, which provides further support for radical cystectomy as the standard for high-risk bladder cancer [80].

PROCEDURAL SELECTION — The primary goals in selecting a urinary diversion are to provide the patient with convenient, low-pressure urinary storage and the best quality of life with the lowest potential for short- and long-term complications.

General principles — Detailed evaluations of patients' medical, physical, and psychological status, as well as their social support systems, are required prior to selection of the appropriate urinary diversion procedure. The decision requires consideration of surgical, oncologic, medical, and psychosocial issues [87].

While patient preference is of the utmost importance, there are some absolute and relative contraindications to the use of various bowel segments and continent urinary reservoirs (table 7). In addition, patients should be informed that intraoperative findings may dictate a change in the planned form of urinary diversion; these include a foreshortened mesentery or cancer-related issues such as a positive urethral margin or gross extravesical disease precluding a negative surgical margin.

Even when an orthotopic neobladder is planned, patients should have a stoma site marked preoperatively by an enterostomal therapist if an ileal conduit is the alternative, in case it becomes necessary based upon intraoperative findings.

General approach — For most patients who require urinary diversion following cystectomy and are candidates for all three procedures, we suggest an orthotopic neobladder [52,63]. In appropriately selected patients, the creation of an orthotopic neobladder obviates the need for an external stoma and preserves body image without compromising cancer surgery. The patient needs to be fully educated about the necessary commitment to the rehabilitation process and needs to possess adequate manual dexterity to perform self-catheterization, if that becomes necessary.

The contraindications for orthotopic neobladder include [88]:

●Insufficient bowel segment length.

●Inability to perform self-catheterization. (See 'Psychosocial and medical considerations' below.)

●Inadequate renal or hepatic function (eg, estimated glomerular filtration rate [eGFR] <45 mL/min/1.73 m²). (See 'Psychosocial and medical considerations' below.)

●Cancer at the urethral margin. (See 'Urethral margin' below.)

●Intractable urethral stricture.

A continent cutaneous diversion may still offer substantial advantages over an incontinent ileal conduit for patients who desire to avoid a stomal appliance but are not candidates for an orthotopic neobladder due to tumor involvement of the urinary outflow tract or who do not desire an orthotopic neobladder. Candidates for a continent cutaneous reservoir should be willing and able to self-catheterize and have sufficient bowel segment length and adequate renal and hepatic function as well.

From the patient's perspective, one of the primary reasons for choosing an orthotopic neobladder over continent cutaneous diversion is the maintenance of normal body image and function. Conversely, continent cutaneous diversion may offer a significantly better quality of life compared with an orthotopic neobladder with respect to social dryness.

An ileal conduit is used for the remaining patients who are candidates for neither option of continent diversion. There is no contraindication for an ileal conduit in patients who can tolerate a cystectomy.

Ileal conduit is the most commonly performed urinary diversion after radical cystectomy worldwide. It is associated with lower morbidity and reoperation rates compared with those of continent diversion options. It is also the procedure of choice for older adults as well as patients with anatomical constraints, poor hepatorenal function, and limited ability to self-catheterize [89].

Oncologic considerations — The primary goal of cystectomy for bladder cancer is control of the underlying tumor, and every effort must be made to avoid compromising the effectiveness of the resection. Disease extent and anatomic considerations can limit reconstructive options.

Urethral margin — Preservation of the urethra in patients with urothelial tumors in order to construct an orthotopic neobladder raises concerns about possible recurrence of cancer, since the transitional cell lining of the urethra may be particularly susceptible to the development of new tumors in these patients. (See 'Recurrent urothelial cancer' below.)

Creation of an orthotopic neobladder requires that the urethra be free of cancer. We recommend performing an intraoperative pathologic assessment of the distal urethral margin at the time of surgery (frozen section) before proceeding with an orthotopic neobladder, rather than relying upon preoperative criteria to predict urethral recurrence [88,90].

●For men, intraoperative frozen section assessment of the urethral margin is required, even if the preoperative evaluation was negative. Transurethral prostatic biopsy was previously performed to assess prostatic urethral involvement prior to construction of an orthotopic neobladder [91]. However, biopsy results do not always correlate with final histology [92,93]. Furthermore, although microscopic involvement of the prostatic urethra may be predictive of a higher rate of urethral recurrence, lower-than-expected urethral recurrence rates have been observed in orthotopically reconstructed patients despite involvement of the prostate. Thus, routine preoperative prostatic biopsies are generally not required, although this can be the surgeon's preference [94].

●In women, creation of an orthotopic neobladder is contraindicated when there is overt involvement of the urethra. Tumor involvement of the bladder neck or invasion of the anterior vaginal wall is associated with an increased risk of concomitant urethral involvement, often representing an absolute contraindication to an orthotopic diversion [95-99]. Such patients should be excluded from orthotopic diversion; however, select women with a negative full-thickness frozen section of their urethral margin can be safely reconstructed to the urethra [100].

Locally advanced disease — Locally advanced bladder cancer and/or regional node-positive disease used to be an absolute contraindication to a continent diversion. The concerns were having to treat a local recurrence and giving chemotherapy and radiation therapy to patients with a urinary reservoir.

The contemporary view is that orthotopic urethral diversions and continent cutaneous diversions can be used in selected patients with regional metastases or locally advanced disease as few such patients will experience complications that would disrupt neobladder function [65,101].

The dwell time of urine in the reservoirs during chemotherapy is a concern and can cause toxicity due to the risk of methotrexate absorption with methotrexate vinblastine doxorubicin cisplatin (MVAC) treatment [102]. This issue has generally been managed by the use of an indwelling catheter during the chemotherapy infusion along with increased hydration [103]. Placement of an indwelling catheter in reservoirs during aggressive hydration required for receiving cisplatin can also avoid the risk of specific issues related to the reservoir, such as overdistension or rupture.

Data are limited regarding the proportion of patients in whom adjuvant chemotherapy is delayed by postoperative complications. However, neoadjuvant, rather than adjuvant, chemotherapy is generally used in patients with muscle-invasive bladder cancer because of a survival benefit [104]. (See "Adjuvant therapy for muscle-invasive urothelial carcinoma of the bladder" and "Neoadjuvant treatment options for muscle-invasive urothelial bladder cancer".)

Minimally invasive urinary diversion — Minimally invasive approaches for radical cystectomy are increasingly being adopted at some centers [105-107]. While all minimally invasive radical cystectomies are performed laparoscopically or robotically, the urinary diversion portion of the procedure can be performed either extracorporeally or intracorporeally due to time and technical constraints.

●Extracorporeal diversion – To date, most randomized trials comparing open with robotic cystectomies have used extracorporeal diversions through a mini-laparotomy and have shown similar short-term complication rates and oncologic outcomes [108-110]. When constructing an extracorporeal urinary diversion, it is important to maintain a robust blood supply to the ureters to minimize the risk of ureteroenteric strictures [111,112].

●Intracorporeal diversion – As more surgeons become comfortable with robotic cystectomy, there is increasing interest in performing intracorporeal urinary diversions [113]. The iROC trial reported that a robotic-assisted radical cystectomy with a completely intracorporeal urinary diversion had some short-term benefits over open cystectomy, including 2.2 (95% CI 0.50-3.85) fewer days in the hospital in the first 90 days, less blood loss, fewer wound complications and venous thrombotic events, and better quality of life scores at up to 12 weeks [114].

With the growing popularity of minimally invasive radical cystectomy, there is also concern that patients who would otherwise be excellent candidates for (open) continent urinary diversions have instead been treated with intracorporeal incontinent diversions [115]. A completely intracorporal approach to both neobladder urinary diversions [116] and cutaneous catheterizable pouches [117] are feasible but present a technically challenging operation.

●A single-center randomized controlled trial of open versus robotic radical cystectomy with extracorporeal diversion reported use of orthotopic neobladder urinary diversion in 55 percent of patients in each arm of the trial [118]. By contrast, in the iROC trial, only 12 percent (19 of 161) in the robotic intracorporeal urinary diversion and only 10 percent (16 of 156) in the open group underwent a continent/neobladder diversion [114].

●While the National Cancer Database demonstrated increasing utilization of minimally invasive approaches for radical cystectomy, the American College of Surgeons National Surgical Quality Improvement Program has shown that utilization of orthotopic neobladder has decreased over time, with now fewer than 20 percent of patients receiving an orthotopic neobladder [119]. Similarly, European countries have also reported declining rates in the utilization of orthotopic neobladder from 33 percent in 2006 to 27 percent by 2014 [120].

While intracorporeal continent urinary diversions have been routinely performed by high-volume robotic bladder cancer surgeons, for less experienced surgeons, performing radical cystectomy robotically should not come at the expense of selecting an incontinent diversion for a patient who is a reasonable continent diversion. Thus, it is critical that surgeons performing robotic cystectomy continue to offer continent urinary diversions to appropriate candidates regardless of whether they perform the diversion through an intracorporeal or extracorporeal after a robotic cystectomy or opt for an open cystectomy with urinary diversion.

Diversion after pelvic radiation therapy — Precystectomy pelvic radiation therapy (RT) was formerly thought to impair functional outcomes (particularly continence) and increase postoperative complications (eg, wound infections, ureteroileal anastomotic leaks) from urinary diversions. These concerns arose from earlier reports of a high incidence of serious complications following salvage cystectomy after failure of primary RT for bladder cancer [121,122].

However, more contemporary studies support the feasibility of continent urinary diversions in irradiated patients [123]:

●In a retrospective series of 86 patients undergoing continent cutaneous diversion with Kock pouch, 44 of whom were previously irradiated, there were no significant differences between irradiated and nonirradiated patients with respect to operative time, intraoperative blood loss, or transfusion requirements [124]. The irradiated group had eight urine leaks (20 percent) with three requiring surgical repair, while the control group had five urine leaks (12 percent) with one requiring repair.

●In a cohort of 18 patients who underwent cystectomy and orthotopic neobladder after pelvic RT, daytime and nighttime continence rates were only 67 and 56 percent, respectively [125]. However, for those with persistent postoperative incontinence, placement of an artificial urethral sphincter successfully restored complete voiding control in all patients with incontinence.

For patients who have had prior radiation therapy, careful attention should be paid to the character, viability, and vascularity of the tissues, particularly the ureters and urethra. The bowel segment to be used for diversion may need to be selected based upon intraoperative findings of irradiated bowel segments. Although the transverse colon has historically been used as a conduit in patients with prior pelvic radiation, there is still risk of ureteral-colonic stricture development [126]. Experience has shown that the ileum can be safely used in carefully selected patients [127]. Orthotopic neobladder reconstruction can also be performed with reasonable functional outcomes at experienced centers [125,128].

Radiation-induced blood vessel damage can result in ureteral stricture rates as high as 32 percent, prolonged incontinence in up to 44 percent of neobladder reconstructions, stomal stenosis in up to 39 percent of catheterizable channels, and fistulas in up to 7 percent [125,129,130]. Reoperation is required to address these complications in 8 to 69 percent of patients; the most common reasons for reoperation include stomal revisions, ureteral anastomotic revisions, and procedures to correct incontinence and repair of fistulas [125,129].

Psychosocial and medical considerations — The choice of urinary diversion has a significant impact on the long-term health-related quality of life for patients who undergo radical cystectomy, and each type of diversion is associated with its own unique set of advantages and disadvantages. Thus, clinicians must first determine if a patient is a candidate for each diversion option and counsel the patient on all feasible options. Only then should an option be selected based upon the patient's values and preferences. Multiple factors need to be considered when choosing the appropriate procedure for an individual patient:

●The patient and caretaker should have realistic expectations about the outcome associated with each reconstruction option. They also need to understand the efforts that will be required on their part during the rehabilitation process. In addition, patients need to have sufficient manual dexterity to master self-catheterization if the decision is made to proceed with a continent diversion. In particular, women who desire a neobladder need to have manual dexterity given the risk of urinary retention. In addition to the clinician, the enterostomal nurse specialist can be invaluable in educating the patient and caretaker and assisting with the decision-making process [131].

●Advanced age can complicate both the procedure and the rehabilitation process. However, physiologic age is more relevant, and no formal cutoff should be applied. Older patients need to be aware that recovery of continence may take longer than in younger patients. Nonetheless, the ultimate results seem to be similar to those achievable in younger patients [132,133]. Our policy is to offer orthotopic neobladder and continent cutaneous diversion to older patients if they are healthy and motivated enough to care for the diversion. If an older patient subsequently becomes unable to care for the continent diversion, then an indwelling Foley catheter may be placed into the diversion, similar to what might be done for the native bladder.

●Obesity increases the technical difficulty of cystectomy and may complicate orthotopic neobladder construction [134]. However, the postoperative management of an ileal loop conduit or a continent reservoir is also more difficult in patients with obesity, and most surgeons do not consider obesity to be a contraindication to reconstruction with an orthotopic neobladder [135]. Many, including the authors, feel that reconstruction to the urethra may be the least complicated reconstructive option for patients with obesity. However, obesity may be associated with a higher incidence of a thickened, foreshortened mesenteric root, which can preclude the ability to anastomose an orthotopic urinary diversion to the native urethra.

●Adequate renal function is required for the creation of any continent diversion. Urinary excretion products are resorbed through the mucosal surface, imposing an extra metabolic burden on the kidneys. Typically, only mild metabolic abnormalities will be observed in patients who have normal renal function. For those with more severe renal dysfunction with serum creatinine values >2.0 to 2.5 mg/dL (180 to 230 microM/L), or an eGFR rate of <45 mL/min/1.73 m², an ileal conduit is preferred over other approaches. (See 'Impaired renal function' below.)

COMPLICATIONS — Reported early and long-term morbidity rates following urinary diversions range between 20 to 56 percent within the first 30 days after surgery, and from 28 to 94 percent beyond 30 days [27,49,136].

When using strict reporting criteria, as many as 64 percent of patients will experience a complication within 90 days of their radical cystectomy, including 67 percent during the operative hospital admission and 58 percent following discharge [137]. The most common complications are gastrointestinal complications (29 percent), followed by infectious complications (25 percent) and wound-related complications (15 percent) [137].

Diversion-related complications are specific to the type of diversion and are generally categorized into those involving the bowel anastomosis, those related to the type of reservoir/conduit, and those associated with the ureterointestinal anastomosis [29]. The complications seen with continent urinary diversions also differ by the time of occurrence (early versus long-term) (table 8) [29,32,48-51]. If one combines the reported percentage of early and late complications in large institutional series associated with each procedure, the risk of having a significant complication over the lifetime of the patient is approximately 8 to 10 percent for orthotopic neobladders and 18 to 38 percent for continent cutaneous reservoirs.

Complications unique to a particular type of diversion have been discussed in the appropriate sections above. Complications common to most or all types of diversions are further discussed below.

Infection — Infectious complications can contribute to acute morbidity and chronic renal insufficiency. Among the contributory factors are the following:

●Intestinal segments that are used to fashion the reservoir/conduit are normally colonized with bacteria [138].

●Incomplete voluntary voiding may leave residual urine, a nidus for infection.

●Intermittent catheterization may introduce bacteria into the reservoir in a retrograde manner, especially if it is done carelessly.

After urinary diversion, patients do not require chronic suppressive antibiotic therapy unless there is a history of recurrent infections. Although the presence of small bowel intestinal mucosa appears to promote asymptomatic bacterial colonization, urosepsis rarely occurs unless the patient has recurrent urinary tract infections. This was illustrated in a series of 66 patients with orthotopic neobladders [139]. Asymptomatic bacteriuria was seen in 78 percent of the 55 patients who voided through an orthotopic neobladder, while only 39 percent developed urinary infection, and urosepsis rarely occurred, except in the context of recurrent urinary tract infections.

Impaired renal function — Progressive impairment of renal function over time is observed in some patients after urinary diversion. The development of urinary tract obstruction (at the site of either ureteral implantation or reservoir/conduit outflow), stones, and chronic infection are contributory factors. Careful surveillance for evidence of obstruction or stone formation and treatment of infection will allow for prompt intervention, which may prevent or minimize loss of renal function.

The most extensive data on clinically important impaired renal function come from a Surveillance, Epidemiology, and End Results (SEER) Medicare database study of a cohort of 4015 patients with normal renal function and no hydronephrosis who underwent radical cystectomy between 1992 and 2010, in which 84 percent were reconstructed with an ileal conduit and 16 percent with a continent diversion [140]. End-stage kidney disease developed in 7 percent of patients; the estimated risks of developing end-stage kidney disease at 5 and 10 years were 8 and 17 percent, respectively.

On multivariate analysis, the risk of developing end-stage kidney disease was not associated with whether patients had an ileal conduit or a continent diversion (hazard ratio 1.06, 95% CI 0.78-1.44). Neither was the choice of urinary diversion independently associated with decreased renal function (measured by estimated glomerular filtration rate) in other studies [141,142].

Absorption of urinary contents in a patient with renal insufficiency can result in chronic acidosis and in osteopenia/osteoporosis from mobilization of phosphate stores. Because ileal conduits have less contact time with urine compared with continent diversion options, they are preferred in patients with existing renal insufficiency. (See 'General approach' above.)

Nutritional and metabolic abnormalities — Exclusion of an ileal or colonic segment of bowel may result in malabsorption of bile salts and vitamin B12.

●Extensive ileal resection can lead to lipid malabsorption and gallstone formation secondary to the loss of bile salts, which are absorbed in the terminal ileum. However, the ileal segments used for urinary reconstruction are generally short enough to avoid this problem [19]. In one study, 10 percent of men and 25 percent of women developed gallstones at a mean follow-up of 41 months after urinary diversion; these incidences were comparable to those seen in the American general population [143]. Excess loss of bile salts can also lead to chronic diarrhea. (See "Gallstones: Epidemiology, risk factors and prevention", section on 'Prolonged fasting/parenteral nutrition'.)

●Vitamin B12 is primarily absorbed by the ileum. Thus, if an ileal segment is used for the urinary diversion, B12 deficiency can develop [19]. The true incidence of B12 deficiency that develops as a result of urinary diversion is unknown; long-term estimates range from 0 to as high as 33 percent five years after urinary reconstruction [56,65]. Periodic monitoring of B12 levels should be considered in all patients who undergo urinary diversion using the terminal ileum, particularly long-term survivors [144,145]. The authors recommend that B12 levels be monitored annually beginning three to five years following diversion and that patients be evaluated and treated for symptoms consistent with B12 deficiency. (See "Causes and pathophysiology of vitamin B12 and folate deficiencies", section on 'Small intestinal inflammation or surgery'.)

The use of any bowel segment for a reservoir or conduit can cause metabolic abnormalities through the resorption of urinary metabolites via the intestinal mucosa [19].

Hyperchloremic metabolic acidosis can result from resorption of excreted metabolites through the intestinal mucosa of the diversion. Severe acidosis was a major problem following ureterosigmoidostomy but is less so with modern reconstructions using ileum and colon that have reduced contact between urine and bowel mucosa [19]. (See "Acid-base and electrolyte abnormalities with diarrhea".)

The long-term effects of uncorrected acidosis include osteomalacia from mineral dissolution and stimulation of osteoclasts. Chronic metabolic acidosis can occur in 5 to 13 percent of patients after urinary diversion, but it takes years of uncorrected acidosis before radiographic evidence of bone demineralization develops [146]. Population-based studies suggest that the risk of fractures increases as much as 21 percent following cystectomy and urinary diversion [147].

To reduce the likelihood of developing bone sequelae from chronic acidosis, patients with a venous bicarbonate level of less than 21 mmol/L should be considered for supplementation with oral sodium bicarbonate and potentially calcium and vitamin D [148-150]. Regardless of the type of diversion, regular monitoring of electrolytes and acid-base status should occur at both early and late follow-up visits to allow for the institution of appropriate corrective therapy as needed.

Intestinal cancer — Bowel segments used to construct urinary diversions are more susceptible to intestinal tumor development than bowel segments in the general population [151]. Chronic exposure to urine causes progressive changes, including relatively thin intestinal epithelium with villous atrophy that initially does not have dysplastic or neoplastic features [152].

The risk after an ureterosigmoidostomy (or variants) is higher than after other types of diversions due to the mixing of fecal and urinary stream [153,154]. The pathogenesis of such tumors remains uncertain but may involve a combination of carcinogenic action and mucosal cellular instability at the anastomotic site, leading first to dysplasia and subsequently to carcinoma. With a ureterosigmoidostomy, adenocarcinoma of the conduit develops after a median latency of 26 years [155]. Patients undergoing ureterosigmoidostomy should be given information concerning this risk and should undergo regular colonoscopic surveillance beginning five years after surgery [156,157].

Reservoir rupture — Spontaneous rupture of either a continent cutaneous reservoir or an orthotopic neobladder is rare [158]. Generally, this has been associated with poor compliance with catheterization of a continent cutaneous reservoir or, rarely, with acute or chronic neobladder overdistention.

RECURRENT UROTHELIAL CANCER — The incidence of urethral recurrence after radical cystectomy ranges from 0.5 to 18 percent [95,159-168]; a meta-analysis including more than 3100 patients described an overall risk of 8 percent [96,167].

Risk factors — Risk factors associated with urethral recurrence after radical cystectomy include multifocal disease, carcinoma in situ (CIS), upper tract urothelial carcinoma, and involvement of the bladder neck or prostatic urethra [95,159-171].

In men, one of the most important risk factors for urethral recurrence is prostatic stromal invasion [90,92,172,173]. In a study of 436 radical cystectomy patients, the five-year probability of urethral recurrence was 6 percent for patients without prostatic involvement, compared with 15 percent for patients with superficial involvement and 21 percent for those with stromal invasion of the prostate [95].

In a study of 235 consecutive patients undergoing radical cystoprostatectomy, 33 percent of specimens had prostatic urothelial carcinoma, of which 64 percent had prostatic stromal invasion [174].

However, patients whose urinary stream has been diverted through the urethra have a lower-than-expected recurrence rate, despite the retention of the urethra. In some series, this has been observed even in men with tumor involvement of the prostatic urethra. In one series of 196 men undergoing cystoprostatectomy and orthotopic urinary diversion, only one had a urethral recurrence despite the finding of microscopic involvement of the prostatic urethra in 13 and foci of CIS in 83 [159].

Thus, although prostate tumor involvement is a risk factor for urethral recurrence, it should not preclude orthotopic diversion, provided that intraoperative frozen section analysis of the urethral margin after radical cystectomy is without evidence of tumor [88,90,160]. (See 'Urethral margin' above.)

Although data are more limited, oncologic outcomes in women appear to be similar to those in men [4,76,175]. As an example, in one series of 145 women with negative margins on frozen section at the time of cystectomy, only two (1.4 percent) developed isolated urethral recurrence [4].

When patients are properly selected for orthotopic diversion, the risk of urothelial recurrence is small, and close follow-up with prompt intervention for urethral recurrence can result in a good oncologic outcome [95,159-168].

Surveillance — Most recurrences are apparent within the first two years following cystectomy, although late recurrences have been reported [95,159-171]. Thus, regular follow-up of the retained urethra is indicated.

We follow patients with a urine cytology using either a voided or urethral wash specimen depending on the diversion, particularly patients at high risk (ie, those with CIS or any prostatic involvement at the time of cystectomy). We also urethroscope any patient with urethral-related symptoms, abnormal discharge, or hematuria.

However, the utility of surveillance programs (ie, urethral wash cytology) to monitor for urethral recurrence following cystectomy is controversial [176]:

●Some studies have not demonstrated a difference in clinical outcome in screened patients compared with those followed clinically [177,178]. As an example, in a series of 176 men undergoing cystoprostatectomy with urinary diversion, urethral recurrence was documented in 13 of 48 monitored individuals (10 of whom underwent urethrectomy) and 16 of 128 patients who were followed clinically (all of whom underwent urethrectomy) [177]. There was no difference in the rate of disease progression regardless of the method of diagnosis.

●On the other hand, proponents of surveillance argue that earlier diagnosis of an asymptomatic urethral recurrence provides a better chance for curative urethrectomy [168]. A poorer outcome in patients with more advanced urethral recurrences has been demonstrated, strongly supporting the use of techniques to detect recurrent disease at an early stage [161].

Management of recurrence — Urethral recurrence often presents with bloody urethral discharge, pelvic/perineal pain, and/or a mass in the urethra [95,159-168] and can occur up to 20 years after radical cystectomy [179].

The management of urethral recurrence after cystectomy is total urethrectomy, including excision of the meatus. Surgical management of these recurrences has limited morbidity, and, when revision of the diversion is indicated, a continent diversion can be maintained [95,159-168].

Transurethral management of noninvasive urethral recurrences has been described [95,162]. With proper patient selection, this approach may obviate a more invasive urethrectomy and revision of the urinary diversion. Intraurethral therapy with bacille Calmette-Guerin (BCG) has been described with mixed results [70,164]. (See "Treatment of primary non-muscle invasive urothelial bladder cancer".)

Patients with urethral recurrence and gross disease on cross-sectional imaging should be considered for systemic chemotherapy. (See "Treatment of metastatic urothelial carcinoma of the bladder and urinary tract".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Bladder cancer" and "Society guideline links: Cystectomy".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Beyond the Basics topic (see "Patient education: Bladder cancer treatment; muscle invasive cancer (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Types of urinary diversion after radical cystectomy – Urinary diversion is required following cystectomy for benign or malignant conditions. Ileal conduit, continent cutaneous diversion, and orthotopic neobladder are the three most commonly used techniques of urinary diversion. (See 'Introduction' above and 'Reconstructive options' above.)

•Ileal conduit – Ileal conduits are the archetypical procedure of incontinent urinary diversions. Urine is directed from the ureters through a segment of isolated bowel to the surface of the abdominal wall via a cutaneous stoma. There, urine drains continuously and is collected by an external appliance adhered to the skin surface. (See 'Ileal conduits' above.)

•Continent cutaneous diversion – Continent cutaneous diversions create a low-pressure reservoir from a bowel segment and connect it to the skin via a continent channel. The patient empties the urine by self-catheterizing the continent channel. (See 'Continent cutaneous diversions' above.)

•Orthotopic neobladder – Orthotopic neobladders connect a bowel segment to the intact urethra. This procedure allows the patient to void volitionally through the urethra, restoring a relatively more natural voiding pattern. (See 'Orthotopic neobladders' above.)

●How to select a method of diversion procedure – For most patients who require urinary diversion following cystectomy, we suggest an orthotopic neobladder (Grade 2C). An orthotopic neobladder obviates the need for an external stoma and preserves the patient's body image without compromising cancer surgery. The patient needs to have sufficient bowel segment length, adequate renal and hepatic reserve, no tumor involvement at the urethral margin or intractable urethral stricture, and the ability to self-catheterize if necessary. (See 'General approach' above.)

•A continent cutaneous diversion may still offer substantial advantages over an incontinent ileal conduit for patients who desire to avoid a stomal appliance but are not candidates for an orthotopic neobladder due to tumor involvement of the urinary outflow tract or who do not desire an orthotopic neobladder. Patients seeking continent cutaneous diversions should be willing and able to self-catheterize and have sufficient bowel segment length and adequate renal and hepatic function.

•An ileal conduit is used for the remaining patients who are candidates for neither option of continent diversion. There is no contraindication to an ileal conduit in patients who can tolerate a cystectomy.

●Intraoperative pathologic assessment before orthotopic neobladder construction – Intraoperative pathologic assessment of the distal urethral margin is recommended at the time of surgery (frozen section) before proceeding with an orthotopic neobladder. Patients should be informed that intraoperative findings may dictate a change in the planned form of urinary diversion. (See 'Oncologic considerations' above and 'General principles' above.)