Hypothesis / aims of study
Radical cystectomy (RC) is one of the most invasive urologic intervention, the reconstruction of orthotopic neobladder offers the advantage of preserving personal integrity by conserving a natural voiding function. Progressively increasing in the number of procedure, the robotic-assisted radical cystectomy with a totally intracorporal reconstruction of an ileal-orthotopic-neobladder (N-RARC) is becoming a reality in many referral centres for robotic surgery . Nevertheless, current literature about the functional characteristics of the robotic reconstructed neobladder is poor and urodynamic data are lacking. Since 2016, a new technique for ileal reconfiguration has been introduced to our institution; following the criteria of the IDEAL guidelines, an L-shaped reservoir has been developed to conjugate the advantage of robotic assistance with an ease and efficient reconfiguration . To date, with 65 patients operated, the surgical technique reached a consolidated grade of standardization, providing convincing oncologic and functional outcomes. We collected data on urodynamic features and we recorded the oncological follow-up of the N-RARC patients with the aim of examining the improvements provided by the robotic assistance and to study the urodynamic features of the L-shaped reservoirs. The results have been compared with a contemporary series of patients underwent to open RC (ORC) with a Vescica Ileale Padovana (VIP) reconstruction in the same institution.
Study design, materials and methods
Since February 2016, a consecutive series of patients undergoing RC with a reconstruction of L-shaped reservoir has been considered; only patients that reached a minimal follow-up of six months were included. The robotic procedures were all performed by the same equip of urologists, during the follow-up every undesired event and disconformable sensations were prospectively recorded in the informatic file system of our hospital and then collected in a database. Demographic features (age, BMI, smoking status, ECOG and Charlson Comorbidity Index (CCI) scores, previous surgery, radio or chemotherapy), preoperatory clinical and pathologic status, as well as preoperative-imaging data, were recorded. Intraoperative and postoperative data were also collected. The urodynamic studies (UDS), comprehensive of the urethral dynamic profile, followed ICS indications for good urodynamic practice and were performed with a timing of six months, considered the minimal lapse of time to reach a sufficient “maturity” of neo-reservoirs. The continence status of patients unable to perform a UDS at our institution underwent a telephonic investigation. We defined social continent (SC) patients using ≤2pads/24 hour and a post void residue (PVR) >100 ml was considered significative. The results of UDS were compared to results of an ORC-VIP and the differences were analyzed with a parametric test or a non-parametric test according to the nature of the variable or with a Chi^2 test when frequencies.
Overall 53 N-RARC have been included, 75.5% of patients were male and the median age at surgery was 66±9 years. 50.9% of cases were diagnosed with a pathologic T stage ≤2 and in 83.5% of patients the N stage was =1. At a median follow up of 10.0 months (IQR= 6.0; 16.0), 8 patients (15.1%) died of a cancer-specific death. 9 patients (17.0%) developed a major complication, according to a Clavien Dindo (CD) scale >2, within 30 days after RC and 11 patients (20.8%), developed a delayed major complication. Table 1 shows the demographic and follow-up characteristics, the continence status and the UDS results for L-shaped N-RARC and ORC with VIP reconstruction. For all the operative and pathologic results, the differences between the groups were not significative, except for the number of lymph nodes in the specimen that was higher in N-RARC.
15 N-RARC patients underwent the UDS at our institution, other 24 patients received the telephonic investigation about continence status.
25/39 (64.1%) patients were SC and 11/39 patients (28.2%) were using no pad or 1 security pad/day.
Among the parameters investigated by UDS, the two types of reservoirs were similar concerning the filling cystometry; the only significative difference was found between the compliance of the reservoirs that reached a value of 29 in the N-RARC and of 16 in the ORC. The cystometric capacity reached similar values of 304 ml (±101) in the robotic group and 275 ml (±107) in the ORC group. In both groups, the neo-bladder filling sensation was delayed, patients referred the “first desire” at a mean volume of 202 (±104) ml among N-RARC and 224 (±79) for the ORC group. The PVR was also similar in the groups, respectively 50 ml (±98) for N-RARC and 82 (±121) for the ORC. Among N-RARC 3/15 (20.0%) patients had a significative PVR and similarly 8/24 (33.3%) among the ORC. The pressure parameters appeared to be similar at cystometric capacity, respectively N-RARC and ORC-VIP reached 30 and 29 cmH2O. A not significative difference has been observed between the two groups for the pressure and the volume of leak point: the N-RARC recorder a mean leak point at 60cmH2O/226ml while the ORC settles the mean maximal pressure/volume before leaking at 37cmH2O/159ml.
Some ileal phasic contraction were recorded during the filling phase of cystometry in both groups with a similar rate of 43% among N-RARC and 35% among ORC.
At the urethral pressure profile, we discovered a not significative difference for closing pressure: 53 cmH2o (±26) for the robotic reservoir and 53 cmH2O (±17) for the ORC group.
Interpretation of results
We described the functional results of a new type of L-shaped ileal reservoir performed with robotic assistance that showed the interesting advantages of being easy to reproduce and to offer good functional outcomes. Despite the lack of data on some patients of our series, the results obtained by UDS are solid and consistent; when compared to a more standardized technique like the ORC-VIP the differences are imperceptible. The robotic dissection during RC provides probably a major precision and subsequently lower impact on the anatomical structure preponed to continence. Contrarily to what is possible in open surgery, a precise mensuration of the length of the ileal segment adopted for reconfiguration is hard to perform. Nevertheless, we found a good volume in our reservoirs and a good voiding capacity during micturition, even if we did not adopt any specific device to measure the length of the ileum. The higher compliance of our robotic reservoir is probably due to the different shape and maybe to a major volume. Likely, it also depends on a good vascularization status of the ileal segments that helps to avoid fibrotic transformation of bowel loops and loss of tone in the mucosa layer. The outcome of continence and of dry status are similar to other series reported in the literature.
Moreover, these results describe the first fifty procedures performed at our institution and prove that this type of neobladder is somewhat easier to reproduce than a VIP.