Postoperative complications and determinant of selecting non intracorporeal urinary diversion in patients undergoing robot-assisted radical cystectomy: an initial experience

Introduction

Radical cystectomy with urinary diversion (RCUD) is a gold standard treatment for non-metastatic muscle-invasive and non-muscle invasive high-risk superficial bladder cancer (1). RCUD is a complex surgical procedure, and ideally, it should be conducted at high-volume tertiary centers by experienced surgeons. According to experts, RCUD is still associated with a high risk of complications (1).

In 2003, Menon first introduced robot-assisted radical cystectomy (RARC) with extracorporeal urinary diversion (ECUD) (2). During the last few decades, RARC has gained popularity and has been rapidly expanding in North America and Europe, and in Japan, RARC has been expanding since 2018 after being covered by public insurance (3,4). According to the results from a systematic review and meta-analysis, the benefits conferred by RARC compared to open cystectomy were a decreased need for blood transfusion and earlier hospital discharge but RARC did not have impact on oncological, safety and quality of life outcomes in the patients (5). In a prospective randomized controlled study (RAZOR), the overall adverse event rates were 67% and 69% for patients receiving RARC and open RCUD, respectively, and infectious and gastrointestinal events were the most common complications in both the groups (6). RARC remains a technically complex procedure requiring considerable experience and advanced techniques, so it is meaningful to retrospectively investigate our initial experience with RARC, which was performed at a representative non-high-volume center in Japan.

The primary endpoint of this study was to evaluate postoperative early (within 30 days) and late (within 90 days) complications and to analyze pre- and peri-operative factors associated with these complications. The secondary endpoint was to evaluate factors correlated with selecting ECUD or cutaneous ureterostomy rather than intracorporeal urinary diversion (ICUD) for urinary diversion. We present this article in accordance with the STROBE reporting checklist (available at https://tcr.amegroups.com/article/view/10.21037/tcr-23-1234/rc).

Methods

Patients

This retrospective, single-center, observational cohort study described the postoperative complications following RARC at our institution. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). This study was approved by the Institutional Review Board of the Clinical Research Ethics Review Committee of Mie University Hospital (No. H2021-258 and No. H2023-182) and individual consent for this retrospective analysis was waived. From August 2019 to March 2023, 50 consecutive patients who underwent RARC for histologically proven muscle-invasive bladder cancer (MIBC) or high-risk non-MIBC with an indication for radical cystectomy according to the Japanese Urological Association Guideline 2019 were included. If clinical T stage was higher than cT2 or lymph node metastasis was suspected clinically, eligible patients received two to three cycles of pre-operative chemotherapy cisplatin/carboplatin together with gemcitabine. All patient characteristics were collected retrospectively through a review of inpatient and outpatient medical records on June 30th 2023. The age-adjusted Charlson comorbidity index (aCCI) was calculated according to ICD-10 (International Classification of Diseases 10th Revision) codes (7,8).

Surgical procedure

All robot-assisted surgeries were performed using the DaVinci Surgical System Xi (Intuitive Surgical, Inc. Sunnyvale, CA, USA). If the upper urinary tract urothelial carcinoma was complicated, laparoscopic or robot-assisted nephroureterectomy was performed before radical cystectomy. Surgical procedures for bladder cancer were divided into the following parts: pelvic lymph node dissection, RARC with urethrectomy, and urinary diversion to maintain a surgeon’s concentration, reduce fatigue, and train young urologists, as described by Nakane et al. (9). As for RARC, seven or six trocars were settled; the seventh trocar was placed in the midline just above the pubic bone for ICUD. The patients were placed in a 25° Trendelenburg position under general anesthesia, and pelvic lymph node dissection was initiated in the majority of cases. Pelvic lymph node dissection included removal of lymph nodes from an area around the bifurcation of the aorta, laterally by the genitofemoral nerve, distal to the deep circumflex iliac vein and Cloquet’s lymph node, and posteriorly by the internal iliac vessels, including the sacral nodes and obturator fossa. If the clinical stage was less than cT2, the sacral nodes and common iliac nodes cranial to the crossing of the ureter were omitted. Lymph node dissection was also omitted in patients with advanced age and severe complications.

RARC was performed according to the procedures reported by Menon (2), without the nerve-sparing method. Urethrectomy was performed, except in cases with urinary diversion using a neobladder. The ICUD ileal conduit procedure has been previously reported (10). Briefly, the ileocecal junction was identified, and the terminal 15–20 cm of the ileum was spared. About 15–20 cm segments of the ileum were chosen for the ileal conduit. An endovascular stapler and cutter (endoGIA, Covidien, Norwalk, CT, USA) with a 60-mm or 45-mm vascular load was introduced into the suprapubic port. Thereafter, the stapler was placed across the bowel and mesentery to ensure perpendicular orientation to the bowel. After firing the stapler and dividing the bowel and mesentery, an identical procedure was performed at the other end of the bowel segment. Bowel continuity was restored above the segment selected for the ileal conduit. Identification of the proximal and distal ends of the ileum and excision of a small amount of the stapled bowel at each end, followed by an endovascular stapler and cutter (endoGIA, Covidien, Norwalk, CT, USA) with a 60-mm vascular load, was introduced into the suprapubic port and stapled to create a side-to-side, functional end-to-end anastomosis. Another 60-mm stapler was introduced and stapled using the same procedure to prevent anastomotic stenosis. The remaining bowel opening was closed using a 60-mm stapler introduced in the assistant 12 mm left lateral port.

The distal ends of both ureters were held in position using the fourth robotic arm for ureteroileal anastomosis using the Wallace method. The ureters were partially transected, spatulated using robotic scissors, and sutured together with 4-0 Monocryl absorbable running sutures. The lateral edges of the newly conjoined ureters were anastomosed to the proximal end of an open ileal conduit segment, by 4-0 Monocryl absorbable running suture. 6-Fr single-J ureteral stent with a guidewire was introduced into each ureter through the suprapubic port. Intestinal laparoscopic forceps introduced from the fourth robotic port were gently guided through the entire loop, starting at the previously made opening at the distal conduit and passed up to the proximal end of the conduit. The stents were secured using forceps and passed through a conduit. 4-0 Vircyl Rapide suture was used to suture the stents to the ureter or conduit: the left stent to the left ureter and the right stent to the conduit to prevent accidental dislodgement. Finally, the anterior opening of the ureteroileal anastomosis was accomplished a 4-0 Monocryl absorbable running suture over the stent. The distal end of the conduit was removed through the pre-marked ostomy site, and the proximal end of the conduit was retroperitonealized by the peritoneum on the right side of the sigmoid colon. An ECUD was performed in a mini-open incisional fashion: a 5–7 cm incision centered on the naval using the same steps as ICUD.

In the case of an orthotopic ileal neobladder, we typically used a U-shaped reservoir described by Koie et al. (11).

Complications

We retrospectively collected data on patient characteristics, perioperative outcomes, and all perioperative complications within 30 and 90 days after surgery. Complications were reported according to the Clavien-Dindo classification system and defined as overall (any grade), low (grades 1–2), and major (grades 3–5) complications. Postoperative ileus was defined as oral intake intolerance after cystectomy, or nausea and emesis accompanied by abdominal distension requiring gastrointestinal rest at any time postoperatively. We also collected complication data related to surgical intervention for RARC.

Selection of urinary diversion methods

Since one of the authors (T.I.) has experienced more than 15 cases of ICUD ileal conduit or neobladder in a previous institution, our fundamental strategy is to perform ICUD when we use the ileum for urinary diversion. However, we selected EUCD or cutaneous ureterostomy for the following specific reasons: lack of proficiency as a team to perform ICUD, patient’s age or comorbidities, single kidney, and patient’s history of abdominal surgery. The reasons for selecting ECUD were retrospectively collected through a review of the inpatient and outpatient medical records.

Statistical analysis

Differences in the demographic features between cases with low and high complications within 30 and 90 days after surgery by Mann-Whitney U test or Chi-squared test and P values less than 0.05 were considered significant. There was no missing data. All analyses were performed using EZR version 1.61 (Jichi Medical University Saitama Medical Center).

Results

Table 1 shows the preoperative, perioperative, and pathological characteristics of the patients. Urinary diversion included ileal conduit, neobladder, and cutaneous ureterostomy in 35 (70%), 6 (12%), and 7 (14%) either by ECUD or ICUD. Cystectomy with bilateral nephroureterectomy was performed in two cases (4%). A total of 27 (54%) and 19 (38%) patients underwent extended, standard, or limited (only obturator lymph nodes) lymphadenectomy, respectively, whereas 4 (8%) patients did not undergo lymphadenectomy because of older age, patient complications, or palliative reasons for cystectomy for local control. Among 50 patients 9 had positive lymph node metastasis. Median positive lymph node number was 3 (maximum 18, minimum 1; IQR, 1–7) and median lymph node density (the number of positive nodes divided by total number of resected nodes) was 8.5% (maximum 63%, minimum 2.3%; IQR, 5–33%).

Table 2 shows pre-operative and peri-operative features of patients who received ileal conduit and compared them between ICDU and ECUD. Obviously, console time was significantly different between ICUD and ECUD. Interestingly, time to diet was shorter in patients who received ICUD than ECUD and it was statistically significant. However, there was no difference in G3 or higher complications within 30 and 90 days post-operation between cases with ICUD and ECUD.

Tables 3,4 show postoperative complications and grades. Briefly, 33 (66%) and 31 (62%) patients experienced complications during the first 90 and 30 days after RARC, respectively. Among them, 19 (38%) and 18 (36%) patients developed G2 complications, and 12 (24%) and 11 (22%) developed major complications during the first 90 and 30 days after RARC, respectively. The most common complications were gastrointestinal complications (24%) and urinary tract infections (22%). Nine patients (18%) underwent surgical intervention within 90 days of undergoing RARC.

Table 5 shows relation with preoperative/perioperative factors and complications. Higher infusion volume during the operations was significantly correlated with the occurrence of major complications both within 90 days (P=0.025) and 30 days (P=0.0158) after RARC, respectively.

Figure 1 summarizes the reasons for selecting ileal conduit/neobladder ECUD or cutaneous ureterostomy. Twelve patients received an ECUD ileal conduit or neobladder, and among them, five cases were selected because our team had been too immature to perform ICUD even though one of the authors (T.I.) had experienced more than 15 cases of ICUD ileal conduit or neobladder. Three patients underwent ECUD due to intraabdominal adhesions for previous abdominal surgery or radiation (gastric cancer, intestinal tumor, and chemoradiation for bladder cancer at a previous hospital). Among them the case with previous surgical history for intestinal tumor, was hard to pursue ICUD, so we determined to convert ICDU to ECUD during surgery; even if we attempted to move the intestinal tract to the cranial side with the head in a low position, it did not move to the cranial side and interfered with the field of vision. The remaining four cases received an ECUD ileal conduit due to comorbidities and advanced cases (palliative surgery) to shorten the surgery time.

Figure 1 Reasons of selecting non-intracorporeal urinary diversion. ECUD, extracorporeal urinary diversion.

Discussion

We investigated complications following RARC performed at a single institution and the factors affecting the occurrence of complications. We also investigated why ECUD or cutaneous ureterostomy was selected for urinary diversion. In Japan, most radical cystectomies for bladder cancer have been performed using open approaches until April 2018, when RARC was covered by public health insurance and has become rapidly widespread (4). Therefore, most doctors, except one of the authors (T.I.), had no experience with both laparoscopic cystectomy and RARC at our institution, which might be a similar situation in most of the hospitals in Japan. Therefore, it is meaningful to summarize our initial RARC experiences, focusing peri- and post-operative complications, for sharing information to prevent and manage complications following RARC.

The present study reported overall complication rates of 66% and 62% during the first 90 and 30 days after RARC, respectively, and major complication rates of 24% and 22% during the first 90 and 30 days, respectively. Of the nine patients who underwent surgical intervention within 90 days, 7 (14%) had gastrointestinal complications (12,13).

Previous studies have shown that the overall complication rates after RARC vary from center to center (14). Recently, Yamada et al. collected data on all complications after radical cystectomy, including open, laparoscopic, and robot-assisted, from a large cohort in Japan (15). In their study, the overall complication rate was 69%, and that of high-grade complications was 25% within 90 days in the current cohort (15), which was relatively similar to the rate observed in our cohort. Recently, a review of the Asian Robot-Assisted Radical Cystectomy Consortium database was published (16). The overall complication rate was 49.2%, whereas high-grade complications were 15.6% (16). The rate was relatively excellent, which might be because the Consortium is organized by nine academic institutions located in Asia and Australia, including two high-volume centers in Japan. Wijburg et al. performed a retrospective analysis of all consecutive RARC cases with intracorporeal reconstruction from nine European high-volume hospitals with ≥100 cases [European Association of Urology (EAU) Robotic Urology Section Scientific Working Group] (17). They analyzed the learning curve for RARC in terms of 90-day major complications (MC90), 90-day overall complications (OC90), operative time, estimated blood loss (EBL), and length of hospital stay. In total, 137 and 97 cases were needed to achieve a plateau at 14% and 48% for MC90 and OC90, respectively, which was longer than these outcomes than reaching a plateau for operative time and EBL (17). Piazza et al. reported the outcomes of RARC by two expert surgeons with extensive experience (>1,000 procedures) in robotic surgery. The rates of OC90 and MC90 after RARC were 46% and 16%, respectively, which were similar to the results of the EAU Robotic Urology Section Scientific Working Group (18). Compared to high-volume centers worldwide, the number of cases per institution is relatively small in Japan. Therefore, we divided the surgical procedures into three steps: pelvic lymphadenectomy, cystectomy with urethrectomy, and urinary diversion as modified version by Nakane et al. (9). This modified “Trisection method” may help the next generation of surgeons experience complex surgical procedures under the supervision of senior surgeons with limited cases in most institutions in Japan. At our institution, the major complication rate was not different between the first 25 cases (mostly performed by surgeons who had experience with more than 40 cases of RARP: first-generation surgeons) and the remaining 25 cases (performed by second-generation surgeons who were instructed by first-generation surgeons) (data not shown). However, from a safety perspective, the ability to safely complete a robotic-assisted radical prostatectomy is mandatory for the next generation surgeon before starting RARC, and this point should not be overlooked. We are still on the learning curve of RARC to achieve the level of experts; thus, we need more cases to perform RARC carefully to reduce these major complications.

The complication rate after RARC may vary according to patient background. We analyzed factors correlated with the occurrence of major complications within 30 and 90 days after RARC. Infusion volume during the operation was the only significantly different factor between patients who experienced major complications and those without complications. Kauffman et al. previously reported that on multivariate analysis, age ≥65 years, operative blood loss ≥500 mL and intraoperative intravenous fluids >5,000 mL were significantly associated with postoperative major complications (19). In their cohort, 49% and 16% of patients suffered overall and major complications after RARC, respectively (19). They also found that intraoperative intravenous fluids >5,000 mL were significantly associated with postoperative overall complications (19). Possible pathophysiological mechanisms of increased complications associated with excess body fluid may lead to ileus (increased gut edema) and impaired wound healing or infection (reduced lymphatic drainage and oxygenation) (20). However, when we divided the cases into the first 25 cases and the remaining 25 cases, the infusion volume during the operations was not significantly different between patients in the last 25 cases who suffered major complications after 30 and 90 days and those without complications (data not shown). Thus, more RARC cases are needed to evaluate the factors associated with major complications after RARC.

Although RARC has become a minimally invasive procedure for patients who undergo radical cystectomy, especially at high-volume centers, most patients eligible for surgery have comorbidities that make us hesitate to perform the surgery. ICUD is a technically challenging procedure and may require longer operative times while mastering the skill and has the potential for increased early perioperative complications; thus, ECUD may have been preferred in the majority of non-high-volume centers in Japan (21). In this report, we investigated the reasons for selecting ECUD or cutaneous ureterostomy in our institution. Excluding cases while mastering RARC procedures, the main two reasons were (I) intra-abdominal adhesions associated with a history of prior abdominal surgery that may make manipulation of the bowel in the abdominal cavity difficult and (II) patients’ comorbidities or age. However, increased experience with ICUD could shorten the operative time compared to ECUD and may become a preferred method of urinary diversion for patients with comorbidities or older age (22). Additionally, as Kadoriku et al. described in their article, ICUD ileal conduit is comparable to cutaneous ureterostomy in terms of oncological prognoses and perioperative outcomes, and can be performed safely in older patients (23).

The present study had some limitations. First, it was a retrospective study with a small sample size. Second, this study included heterogeneous patient characteristics: patients who underwent RARC and hemi- or bilateral nephroureterectomy, ICUD or ECUD ileal conduits, ICUD or ECUD neobladder, and cutaneous ureterostomy. Third, the follow-up duration was too short to evaluate the overall survival and late-phase complications (more than 90 days after RARC). Fourth, eight surgeons performed the operations; therefore, our results included technical and individual surgeon biases. Fifth, we have not yet applied enhanced recovery after surgery (ERAS) protocol for RARC, which may reduce incidence of post-operative ileus (24). Sixth, the frailty status of each patient was not assessed. Frailty may be associated not only with post-operative complications after RARC, but also with the prognosis of bladder cancer patients who have undergone radical cystectomy (24-26). Therefore, preoperative evaluation of frailty using the G-8 score could be a useful tool for predicting post-operative complications in patients.

Based on this assessment, perioperative nutrition therapy and physiotherapy for frail patients might reduce the rate of complications after RARC.

Seventh, our cases had high EBL and blood transfusion rate than those reported previously (27). Our EBL included urine spilled out in the operation field especially when performing ICUD, so thus it is relatively difficult to determine precise blood loss. Therefore, we think that our EBL was higher than the previous reports. Among 50 cases, 68% of the patients received pre-operative chemotherapy in our series. The percentage was higher than the previous reports (28), thus our cases might had relatively low reserve capacity for blood loss and needed transfusion. However, we need more cases to reach a plateau of EBL as indicated in reports by Wijburg et al. (17).

Conclusions

Surgical complications related to the initial experience with RARC at a non-high-volume center in Japan cannot be ignored. Although this complicated surgical procedure requires a learning curve to achieve a stable rate of much fewer major complications after RARC, careful assessment of patients’ status before surgery and critical postoperative management may reduce complication rates more quickly, even at non-high-volume centers.

Acknowledgments

Funding: This research was funded by JSPS KAKENHIGrant Number 21H03066 to T.I.

Footnote

Provenance and Peer Review: This article was commissioned by the Guest Editor (Takuya Koie) for the series “Current Status of Robotic Surgery for Genitourinary Diseases in Japan” published in Translational Cancer Research. The article has undergone external peer review.

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://tcr.amegroups.com/article/view/10.21037/tcr-23-1234/rc

Data Sharing Statement: Available at https://tcr.amegroups.com/article/view/10.21037/tcr-23-1234/dss

Peer Review File: Available at https://tcr.amegroups.com/article/view/10.21037/tcr-23-1234/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tcr.amegroups.com/article/view/10.21037/tcr-23-1234/coif). The series “Current Status of Robotic Surgery for Genitourinary Diseases in Japan” was commissioned by the editorial office without any funding or sponsorship. T.I. reports that he receives a grant (No. 21H03066) from JSPS KAKENHI. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). This study was approved by the Institutional Review Board of the Clinical Research Ethics Review Committee of Mie University Hospital (No. H2021-258 and No. H2023-182) and individual consent for this retrospective analysis was waived.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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