Safe transition from extracorporeal to intracorporeal urinary diversion following robot-assisted cystectomy: a recipe for reducing operative time, blood loss and complication rates

Radical cystectomy with extended pelvic lymph node dissection is the standard treatment for muscle-invasive and high-risk non-muscle-invasive carcinoma of the bladder [1]. Over the last decade, robot-assisted radical cystectomy (RARC) is increasingly being utilized in a number of institutions to reap the benefits of minimally invasive surgery [2‐5] while replicating principles of open surgery and maintaining oncological equivalence [6]. These benefits include a reduction in postoperative morbidity and an earlier return to normal activities.

Most of the literature evaluating RARC, including four randomized trials comparing RARC with open radical cystectomy [7‐10], have used extracorporeal urinary diversion (ECUD), deemed a simpler and quicker procedure than intracorporeal urinary diversion (ICUD). With increasing surgical experience, ICUD is increasingly being adopted allowing for potential benefits, including decreased fluid loss, reduced estimated blood loss (EBL), less pain, smaller incisions, a faster return of bowel function and fewer anastomotic strictures [11]. At present, there are limited studies comparing perioperative outcomes of ICUD and ECUD [12‐14].

We established a RARC program in our institution in 2004 and completed the transition from ECUD to ICUD in October 2016. The objectives of this study are to report on the perioperative outcomes and postoperative complications following our transition to ICUD.

RARC is a technically complex procedure consisting of three parts: extirpation of the bladder, pelvic lymph node dissection, and finally, urinary diversion. Patients with bladder cancer undergoing cystectomy are often elderly, chronic smokers and have multiple comorbidities. This makes the surgical procedure more challenging, and recovery, on occasion, unpredictable. ECUD is the most commonly performed technique in most centers when compared to ICUD as it is deemed quicker and technically less demanding. Ahmed et al. [13] performed an analysis of the International Robotic Cystectomy Consortium (IRCC) database, and 82% of the 935 patients received an ECUD, with only 18% of urinary diversions constructed intracorporeally.

However, with increasing surgical experience, rates of ICUD are increasing, due to its potential perceived benefits over ECUD. These include decreased fluid loss from evaporation, reduced EBL, less pain, smaller incisions and earlier return to normal bowel function [11]. Wound-related benefits may be even greater in females as the specimen can be extracted via the vagina and thus obviate the need for open extraction. There are, however, limited studies comparing perioperative outcomes of ECUD and ICUD, especially in centers transitioning from one to the other. To the best of our knowledge, our study is the largest comparing perioperative outcomes and complications from a unit transitioning between diversion techniques. We have performed RARC with ECUD since 2004 at our center [3] and transitioned to ICUD in October 2016. Late adoption of ICUD was a conscious decision to await the early published results of ICUD. It was felt that urinary diversion was a critical step in determining morbidity, functional outcomes and bowel recovery. The outcomes of our first 59 intracorporeal ileal conduit cases compared to our last 68 extracorporeal cases showed no differences in terms of patient demographics and oncological characteristics, but we found that ICUD resulted in benefits of shorter operative times, lower EBL, and 30-day complication rates.

One of the concerns with adoption of ICUD is the perceived longer operative times due to the complexity of intracorporeal bowel handling and suturing, especially early in the learning curve [15]. Having performed RARC in our unit for more than a decade, we did not experience any significant issues transitioning from ECUD to ICUD. In fact, we found that the median total operative time for RARC and intracorporeal ileal conduit to be significantly shorter (330 min compared to 375 min for extracorporeal, p = 0.019). This is likely due to the obviation of the need for undocking of the robot for urinary diversion and the presence of experienced robotic bedside assistants. In addition, despite the training needs of our bladder cancer fellowship program, we believe that a dual console robotic system in our center ensures a safe and efficient training environment and shortens the learning curve of our fellows.

Operative times also improved with experience, with a significantly reduced median operative time for RARC and intracorporeal ileal conduit in the second cohort of 29 cases compared to the first 30 cases (300 vs 360 min, p = 0.004). Our finding of a shorter operating time for RARC with intracorporeal ileal conduit is consistent with Novara et al.’s systemic review, which reported a mean operative time of 360 min for extracorporeal ileal conduit compared to 340 min for intracorporeal ileal conduit [16]. However, Ahmed et al.’s review of the IRCC database did not find a significant difference in the operative times between ECUD and ICUD [13]. Guru et al. described their experience transitioning from ECUD to ICUD in twenty-six patients (thirteen patients underwent ECUD and ICUD, respectively) [12]. They found that operative times were similar between the two groups. The only other published study of a unit transitioning from ECUD to ICUD was by Pyun et al. [14]. Their study consisted of 64 patients, 38 of whom underwent ECUD and 26 had ICUD. They noted ICUD resulted in significantly longer operative times (468 min for ECUD and 581 min for ICUD, p < 0.05).

We also found that ICUD resulted in lower EBL compared to ECUD (300 vs 425 ml, p < 0.035). We believe that the pneumoperitoneum and superior vision offered by utilizing the robotic approach for ICUD helped reduce blood loss by allowing more precise dissection and improved bowel division and anastomosis. The majority of the complications following radical cystectomy are usually a result of this complex reconstruction. A potential advantage of ICUD is reduced bowel handling with limited peritoneal cavity exposure to air. This is associated with reduced postoperative systemic inflammatory response and therefore improves bowel recovery [17, 18]. In our study, we noted a lower 30-day overall complication rate of the ICUD group compared to ECUD (48.4 vs 71.4%, p = 0.008). Our findings of a lower EBL and 30-day overall complication rate in favor of ICUD is mirrored in Pyun et al.’s study of their transition from ECUD to ICUD [14]. They reported a reduction in mean EBL from 265 to 148 ml (p < 0.001) and less overall complications in the ICUD group (30.8% for ICUD and 57.9% for ECUD, p = 0.033).

Our study, however, has some limitations. First, although this study had the largest cohort to date, the sample size was still relatively small. Second, despite our patient demographics and the oncological characteristics being similar between groups, there still remains a degree of selection bias due to the non-randomized nature. In addition, with a limited follow-up of these patients, there remains a long-term uncertainty with regards to outcomes between ECUD and ICUD. We are one of the participating institutions in the Phase III prospective multi-center randomized controlled trial comparing the outcomes from intracorporeal robotic-assisted radical cystectomy with open radical cystectomy (iROC trial) [19], and the results of this study will provide level 1 evidence on the outcomes of ICUD compared to open surgery.

In conclusion, our experience has shown that transitioning from ECUD to ICUD after RARC has specific benefits including shorter operative times, reduced EBL, and lower 30-day complication rates.