ORTHOTOPIC SIGMOID RESERVOIR: MORE THAN TWENTY YEARS EXPERIENCE

The aim of this study is to present 23 years of experience with sigmoid orthotopic neobladder (SON) to explain the advantages of the technique. We assess functional and oncological outcomes and describe complications. We retrospectively evaluated 167 patients who underwent SON reconstruction, from Jan 1993, using a detubularized 20-25 cm segment: 141 (88.2%) male and 19 (11.8%) female, 7 (4.19%) lost at follow-up (FU). Urodynamic evaluation was performed in all consenting patients after 6 months, 2, 5 year and 10 ys. Survival is estimated at 5 and 10 ys according to specific clinicpathological variables of interest. Uni and multivariate Cox regression and log-rank analysis were used. ANOVA was used to investigate urodynamic finding differentials. There were 85 (53.1%) deaths and 75 (46.9%) living at the end of the study period (mean follow-up: 6.8 ys, SD: 6.1; median 4.71, range 0.07 - 21.5). Early complications occurred in 36 patients (22.6%), late in 40 (25%), Chronic Kidney Disease developed in 2 (1.3%) because of ureteral stenosis, one (0.6%) developed hyperchloremic metabolic acidosis. Mean Creatinine level at the end of follow-up is 1.22 mg/dl. Daytime continence was achieved by 81.8% at 5 years and was unchanged at 10. Urodynamic results are listed in table 1. A significant difference in maximum neobladder capacity between six months and two years follow-up and between two and five years has become clear (p<0.001 and p¼0.03, respectively). No significant difference between five years and ten years follow-up is evident (p>0.05). Moreover, data showed a significant statistical difference in PVR values between six months and two years follow-up and between two and five years (p<0.01 and p<0.05 respectively), but no difference between five and ten years. No statistical difference was demonstrated in maximum flow rate (QMax), max neobladder pressure and reservoir compliance in any followup evaluation. A statistical difference in neobladder pressure at maximum capacity between two years and five years urodynamic evaluation (p<0.01) has been found. Advantages of a SON are its low tendency to hyper-dilatation, a good filling sensation, high continence rates, and its insignificant metabolic effects. SON higher endoreservoir pressure does not significantly impact upper urinary tract function.