Sigmoid Colon Neobladder
The sigmoid (left colon) neobladder is an orthotopic bladder substitute constructed from a detubularized segment of sigmoid colon and anastomosed to the native urethra, offered as an alternative to the more common ileal neobladders when the sigmoid is better suited to the patient's mesenteric anatomy, bowel history, or surgeon preference. It is a total bladder replacement after cystectomy, distinct from sigmoid cystoplasty, which augments a retained native bladder.[1][2]
Rationale and Patient Selection
Candidacy follows the same general requirements as any orthotopic reconstruction: an oncologically appropriate urethra, adequate sphincter function, and a patient able and willing to learn abdominal straining and scheduled voiding, with acceptance of possible nighttime incontinence or catheterization. See Urinary Diversion Principles for general orthotopic selection criteria. The sigmoid has been proposed over an ileal segment when the left colon offers a shorter, broader mesenteric reach to the pelvis on the sigmoid-artery pedicle, when ileal length or quality is a concern, or according to surgeon experience; no comparative trial establishes that sigmoid substitution is preferable to an ileal neobladder for any specific patient group.[2][3]
Operative Technique
The following sequence has been described for the sigmoid neobladder: a well-vascularized segment of left colon is isolated on its sigmoid-artery pedicle, keeping the mesenteric incision limited to protect the blood supply; the segment is detubularized along its antimesenteric (medial tenia) border and reconfigured into a dependent, low-pressure pouch; the ureters are implanted with a submucosal antireflux tunnel; and the dependent portion of the reservoir is anastomosed to the urethral stump without tension. Preserving the ipsilateral hypogastric artery during cystectomy and limiting pelvic-floor muscle dissection have been emphasized as technical points relevant to later continence and sexual function.[2] Reported segment lengths have varied; an early technique description used a minimum of 20-25 cm of sigmoid, and a separate chapter description describes 30-35 cm as the length one group of authors considers necessary for a capacious reservoir, substituting another bowel segment when that length is unavailable. These are the stated practice of individual surgeons and series, not a validated minimum.[2][4] A detaenialized (non-detubularized) technique, in which the taenia is incised to open the sigmoid lumen without full detubularization, has also been reported as a technical variant.[5]
Outcomes
Series are retrospective and single-institution, with varying definitions of continence and complications; figures should not be pooled across studies or treated as a single cohort.
| Series | Patients | Follow-up | Key findings |
|---|---|---|---|
| Reddy 1991[1] | 27 | Not specified beyond 1 year | At 1 year, mean capacity 600 mL, filling and capacity pressures low (mean 12 and 16 cm H₂O); all patients continent by day, 67% continent at night without excessive voiding frequency |
| Miyake 2010[6] | 82 (80 evaluated) | Mean 55 months | 73/80 voided spontaneously; daytime and nighttime continence in 69/80 and 46/80; mean maximum flow rate 18.6 mL/s, postvoid residual 24.5 mL; severe hyperchloremic metabolic acidosis in 3; no significant difference in SF-36 quality-of-life scores versus an age-matched reference population |
| Xu 2013 (detaenialized technique)[5] | 210 | Median 48 months | 5-year daytime and nighttime complete continence 74.6% and 57.1%; younger age independently associated with continence; early complications in 31%, late complications in 21.5% |
| Nicita 2016[3] | 160 | Mean 6.8 years (range 0.65-21.7) | Complete (day and night) continence 45% and daytime-only continence 36% at 5 years, stable to 10 years; early complications 22.6%, late complications 25%; stage V chronic kidney disease in 1.3%; capacity and postvoid residual improved significantly between 6 months and 5 years, then stabilized |
| El-Helaly 2019 (sigmoid vs ileal)[7] | 52 (25 sigmoid, 27 ileal) | Not specified | No significant difference between sigmoid and ileal groups in continence, spontaneous voiding, or complication rate; voiding time and volume on free-flow study favored the sigmoid group, while maximum and closing urethral pressures were higher in the ileal group |
The continence rates reported for sigmoid neobladders span a wide range (45% to 100% complete continence, depending on the series, definition, and follow-up), reflecting differences in patient selection, surgical technique, and how continence was defined and measured rather than a single expected outcome.
Complications
Reported complications across these series include wound infection, ileus, pyelonephritis, ureterointestinal stricture, neobladder or enteric stones, entero-urethral stricture, metabolic acidosis, and progressive chronic kidney disease.[3][5][6] As with any bowel-based orthotopic reservoir, lifelong surveillance of renal function, metabolic status, and reservoir emptying follows the general diversion follow-up framework; see Urinary Diversion Principles.
See Also
- Urinary Diversion Principles
- Sigmoid Cystoplasty
- Right Colon Pouch
- Mansoura Neobladder
- Modified Studer Pouch
References
1. Reddy PK, Lange PH, Fraley EE. "Total Bladder Replacement Using Detubularized Sigmoid Colon: Technique and Results." J Urol. 1991;145(1):51-5. doi:10.1016/s0022-5347(17)38245-9
2. Reddy AK, Reddy PK. Left Colon Neobladder. In: Montague DK, Gill IS, Angermeier KW, Ross JH, eds. Textbook of Reconstructive Urologic Surgery. Informa Healthcare; 2008:345-348.
3. Nicita G, Martini A, Filocamo MT, Saieva C, Tosto A, Stomaci N, Bigazzi B, Villari D. "Use of Sigmoid Colon in Orthotopic Neobladder Reconstruction: Long-Term Results." Int J Urol. 2016;23(12):984-90. doi:10.1111/iju.13201
4. Reddy PK, Lange PH, Fraley EE. "Bladder Replacement After Cystoprostatectomy: Efforts to Achieve Total Continence." J Urol. 1987;138(3):495-9. doi:10.1016/s0022-5347(17)43238-1
5. Xu K, Liu CX, Zheng SB, Li HL, Xu YW, Xu AB, Chen BS, Shen HY. "Orthotopic Detaenial Sigmoid Neobladder After Radical Cystectomy: Technical Considerations, Complications and Functional Outcomes." J Urol. 2013;190(3):928-34. doi:10.1016/j.juro.2013.03.072
6. Miyake H, Furukawa J, Muramaki M, Takenaka A, Fujisawa M. "Orthotopic Sigmoid Neobladder After Radical Cystectomy: Assessment of Complications, Functional Outcomes and Quality of Life in 82 Japanese Patients." BJU Int. 2010;106(3):412-6. doi:10.1111/j.1464-410X.2009.09006.x
7. El-Helaly HA, Saifelnasr MK, Mohamed KM, Abdelaziz AS, Youssof HA. "Outcome of Orthotopic Sigmoid Versus Ileal Neobladder Reconstruction." Urol Ann. 2019;11(2):204-10. doi:10.4103/UA.UA_137_18