Clinical Study Of Orthotopic Ileocecal Neobladder After Retrograde Radical Cystectomy

【Background】Bladder cancer is the second most common malignant tumors of the male genitourinary system.Bladder cancer is usually described as muscle invasive bladder cancer（MIBC）and non-muscle invasive bladder cancer（NMIBC）based on the tumor invasiveness and prognosis.For the treatment of MIBC and high-risk NMIBC,radical cystectomy（RC）for bladder and urinary diversion（UD）is considered the gold standard.The most common paths of UD are ileal or colonic conduit,continent cutaneous diversion and orthotopic neobladder（ONB）,among which,the ileal conduit holds the most commonly application for its easy accessibility and reliability.The goals of UD after removal of the bladder have evolved from simple diverting through a conduit to functional and anatomic reconstruction by ONB.Orthotopic neobladder could be the first choice than other techniques attributes to its high similarity like the original preoperative state,long-term oncologic safety and better quality of life for patients free of contraindications.Nowadays,orthotopic neobladder is regarded as a popular and standard form of diversion in many clinical centers of excellence worldwide.Construction of an orthotopic neobladder using existing intestinal segments depends on the healthy external urethral sphincter;large-volume,low-pressure and highly-compliant reservoir and adequate antireflux mechanism.Various gut segments have been used for neobladder construction.However,there is no ideal urinary diversion for all patients.The specific methods should tailor to the patients’needs.Furthermore,patients should be encouraged to participate in the procedure of surgical decision-making.Many surgical techniques have been used to reconstruct different kinds of neobladders including the using of intestinal segment,the configurations of the reservoir and the method of ureteric implantation.The Studer pouch,W?ileal neobladder,orthotopic Mainz pouch and sigmoid neobladder are commonly performed.However,any form of neobladder has its specific problems.The resorption of urinary contents,abnormal peristalsis,better daytime and nighttime continence and long-term upper tract protection remain the problems.We have tried constructing the ileocecal orthotopic neobladder with ileocecum since 2018.The basic principles of the surgical technique of UD after retrograde radical cystectomy were described briefly here:（1）the tubular cecum is used as the reservoir;（2）the freely refluxing end-to-side ureteroileal anastomosis connected to an afferent isoperistaltic ileal limb and the ileocecal valve are used as the antireflux procedure;（3）inversion and end-to-end anastomosis of cecum to urethra.【Objective】To evaluate daytime and nighttime continence,short-term and long-term complications and urodynamic parameters among ileocecal orthotopic neobladder and preliminarily explore the safety and feasibility of the surgery.【Methods】1.Four patients with bladder cancer underwent retrograde radical cystectomy and subsequent neobladder reconstruction in our department between November 2018 and August 2019 were involved.We retrospectively analyzed the continence rates,short-term and long-term complications,the medical imaging tests（intraudio videoenous urography,retrograde urography,CT,etc.）and laboratory examination（hemogram,serum creatinine,renal function,etc.）associated with urinary diversion.2.The urodynamic data of the patients were examined at 6th month and 12th month after surgery,respectively,including maximum cystometric capacity,intravesical pressure,maximum flow rate,post-void residual volume,etc.3.Statistics analysis:for quantitative data,comparison between two groups was done using Student’s t-tests.P-value<0.05 was defined as statistically significant.【Results】1.1/4 of the patients achieved daytime continence,and all patients had enuresis three months after surgery.3/4 patients were able to achieve daytime and nighttime continence six months after surgery.2.Comparison of the preoperative and postoperative follow-up laboratory examination data:hemoglobin was significantly reduced after surgery（131.1±23.8 vs.102.0±19.0 g/L,P<0.05）;None of the 2 anemia patients were megaloblastic anemia associated with vitamin B12 deficiency;No significant difference was shown in contents of K⁺（4.3±0.5 vs.4.0±0.4）mmol/L,Na⁺（139.4±3.3 vs.138.2±3.7）mmol/L,Cl^-（104.6±1.7 vs.102.8±3.6）mmol/L,Ca²⁺（2.2±0.3 vs.2.2±0.1）mmol/L,BUN（5.6±1.1 vs.6.7±3.4）mmol/L,Cr（67.7±14.3 vs.64.6±21.5）μmol/L and e GFR（96.1±12.0 vs.101.2±19.0）ml/min/1.73m².3.Comparison of the follow-up urodynamics data at 6 and 12 months after surgery:The maximum cystometric capacity（303.3±41.4 vs.401.7±53.0 ml,P<0.05）and maximum flow rate（13.9±2.3 vs.18.7±1.5 ml/s,P<0.05）were increased at 12-month compared with 6th month.The post-void residual volume was significantly decreased at12th month（61.6±24.0 vs.21.3±4.4 ml,P<0.05）.Intravesical pressure decreased significantly（30.5±5.4 vs.19.0±5.7 cm H₂O,P<0.05）at 12-month,which is lower than urethral closure pressure（52.9±9.7 vs.53.6±9.4 cm H₂O,P<0.05）during the filling phase;There is no significant difference between intravesical pressure and urethral closure pressure（45.7±6.6 vs.47.7±3.2 cm H₂O,P>0.05）during the voiding phase.【Conclusions】Orthotopic ileocecal neobladder following retrograde radical cystectomy is an ideal urinary diversion,with the advantages of large-capacity and low-pressure reservoir,satisfying continence and feasible techniques.