The initial target market for the da Vinci system was cardiothoracic surgery, attempting to minimize morbidity by avoiding a sternotomy and taking advantage of the precision and fine instrument movement afforded by the robot. Both coronary revascularization and mitral valve repair are currently performed with robotic assistance, but the operations are technically demanding and have not expanded as rapidly as the application to radical prostatectomy. The first laparoscopic radical prostatectomy was performed in 1991 and several centers reported their experiences with the minimally invasive approach in the late 1990s. Despite refinements in techniques and outcomes comparable with those of traditional open prostatectomy, laparoscopic radical prostatectomy remained a challenging operation, with significant learning curve, and was performed by relatively few surgeons. However, the operation ultimately proved to be the ideal application of robotic assistance and over the past decade, it has largely supplanted both open and laparoscopic prostatectomy; in 2010 it is estimated that 80% of radical prostatectomy operations in the United States will be performed with robotic assistance. Moreover the robot is widely available and has been rapidly adopted by surgeons throughout the country, in both community and academic medical centers.
The operation is fundamentally no different than open or laparoscopic radical prostatectomy, with the goals of complete removal of the prostate and seminal vesicles, performing lymphadenectomy when indicated, and preservation of urinary and sexual function. Various approaches have been described including transperitoneal versus extraperitoneal, and for the transperitoneal technique, the initial dissection can proceed either anteriorly (ie, retropubic space and through the bladder neck) or posteriorly (ie, dissection of the seminal vesicles and through the plane between the prostate and rectum). Regardless of technique, the patient must be placed in a steep Trendelenburg position in order to displace the bowels cranially, away from the pelvis. Some patients with underlying cardiac or pulmonary disease or obesity may not tolerate being in this position for a prolonged period. In addition, the abdomen is insufflated with carbon dioxide typically to 15 mm Hg pressure, further affecting pulmonary and cardiac function and requiring carefully monitoring by the anesthesia team. Meticulous attention to patient positioning is critical to prevent neuropraxia in the dark operating room environment; it may also be difficult to assess the patient with the additional equipment and bulk of the robotic system. Once the robot is docked in position with the camera and instruments inserted through the ports, the patient and operating room table cannot be moved until the instruments and robot are disengaged. Factors that make the robotic approach challenging include prior complex abdominal or pelvic surgery, morbid obesity, large prostate or median lobe, and prior radiation or prostate surgery; nevertheless, these are not absolute contraindications and surgery is often feasible despite these factors.
In assessing the success of robotic-assisted laparoscopic radical prostatectomy, the relevant outcomes of cancer control, urinary continence, and sexual function must be evaluated. Compared with open retropubic prostatectomy, robotic-assisted prostatectomy is associated with decreased risks of operative blood loss and need for transfusion.
With respect to oncologic outcomes, open radical retropubic prostatectomy is the gold standard against which new techniques must be compared. Large series of men undergoing surgery at high-volume centers have been published with long-term follow-up and include both pathologic outcomes and biochemical outcomes (Table 10–1). Smith et al (2007) reported lower rates of positive surgical margins in the robotic group compared with the open group (15% vs 35%, p< .001). Similar rates of positive surgical margins have been reported by Ahlering et al (2004) (16.7%), Menon et al (2007) (11%), and Patel et al (2010) (10.6%) and are likely not significantly different when compared with radical retropubic prostatectomy. In two large robotic series, the risk of positive margin was 4% and 13% in pT2 and 34% and 35% in pT3 (Badani et al, 2007; Patel et al, 2008). The risk of biochemical recurrence after robotic prostatectomy appears to be low and comparable with that of open prostatectomy. At median follow-up of 22 months, Badani et al (2007) reported 5-year actuarial biochemical-free survival of 84%. Longer follow-up is required to evaluate if there are significant differences in recurrence-free, and more importantly, cancer-specific survival. Using the SEER-Medicare Linked Database, Hu et al (2009) did not find a difference in rates of utilization of secondary cancer treatments, such as androgen deprivation and radiation therapy, for men undergoing minimally invasive versus open surgery, suggesting that cancer outcomes were similar.
Table 10–1. Perioperative and Oncologic Outcomes of Robotic-Assisted Laparoscopic Radical Prostatectomy from Select Published Series. |Favorite Table|Download (.pdf)
After open prostatectomy, continence rates 1 year after surgery are expected to be ≥90%. Most single institution series of robotic prostatectomy report comparable results, with ≥93% of men being continent 12 months after surgery (Table 10–2). Although there do not appear to be significant differences, men undergoing robotic prostatectomy may have more rapid return of continence. However, data from Hu et al (2009) suggest that men undergoing minimally invasive prostatectomy may have worse urinary outcomes compared with open prostatectomy. The population-based study found an increase in diagnosis of both incontinence and erectile dysfunction. It is important to note that the study did not differentiate between laparoscopic and robotic surgery, covered the early period of minimally invasive prostatectomy (2003–2007), and relied on Medicare claims rather than validated surveys to assess outcomes.
Table 10–2. Urinary Outcomes after Robotic-Assisted Laparoscopic Radical Prostatectomy from Select Series.
The enhanced three-dimensional and magnified visualization of the da Vinci system has led to a better appreciation and renewed consideration of the neuroanatomy of the prostate and parasympathetic innervation responsible for male erections. Techniques developed during the evolution of robotic prostatectomy to improve preservation of nerve bundles include high anterior release of the periprostatic fascia (coined the Veil of Aphrodite) and minimizing the use of thermal energy during dissection around the neurovascular bundles. Whether these maneuvers ultimately improve erectile function is unclear, but the reexamination of technique and anatomy has led to alterations in both minimally invasive and open surgical operations; it is difficult to determine which approach yields the best sexual function. Overall rates of potency after open prostatectomy have been reported to approach 70%, but are largely dependent on baseline function and age (Table 10–3). Approximately 60–70% of patients undergoing bilateral nerve-sparing robotic prostatectomy can be expected to have erections 12 months after surgery. As mentioned, Hu et al (2009) reported an increased diagnosis of erectile dysfunction (26.8 vs 19.2 per 100 person-years) in men undergoing minimally invasive prostatectomy. They also noted that the minimally invasive approach was associated with shorter hospitalization, lower rates of blood transfusion, fewer respiratory and surgical complications, and fewer anastomotic strictures. However, they noted an increased rate of genitourinary complications. Table 10–4 summarizes complications in published robotic prostatectomy series.
Table 10–3. Sexual Function Outcomes after Robotic-Assisted Laparoscopic Radical Prostatectomy from Select Series.
Table 10–4. Reported Complications after Robotic-Assisted Laparoscopic Radical Prostatectomy from Select Series.
Similar to laparoscopic radical prostatectomy, laparoscopic cystectomy was reported to be feasible early in the evolution of laparoscopy (1992) but was infrequently performed due to the technical challenges and limitations in instrumentation, prolonged operative time, and need for complex reconstruction. With increasing laparoscopic skills and experience with radical prostatectomy, more reports of laparoscopic cystectomy emerged and the operation developed over the past decade, with robotic-assisted cystectomy a natural progression given the benefits provided by the robot. Nevertheless, it remains a difficult operation given the need for meticulous cancer excision, extended lymphadenectomy in all cases, and urinary tract reconstruction.
The primary indication for robotic cystectomy includes patients with muscle-invasive or high-risk/refractory noninvasive urothelial carcinoma of the bladder. The operation has been reported to be feasible in both men (cystoprostatectomy) and women (anterior pelvic exenteration), and it also includes removal of the pelvic lymph nodes. Most surgeons perform the extirpative portion of the operation using the robot, and then make a small lower abdominal incision to extract the specimens as well as perform the urinary diversion; however, a purely minimally invasive approach to the entire operation has been described and is feasible, but it is time consuming and potentially of little additional benefit.
Most series regarding robotic cystectomy are single-institution, nonrandomized case series. Nix et al (2010) report the only prospective, randomized trial comparing robotic versus open radical cystectomy for bladder cancer in a total of 41 men. The primary endpoint evaluated was the lymph node yield, and the mean number removed in the robotic and open groups was 19 and 18, respectively. There were no significant differences with respect to positive surgical margins or perioperative outcomes, including length of hospitalization and overall complication rate. The same group reported no case of positive surgical margin in 100 consecutive cases of robotic radical cystectomy (Pruthi et al, 2010), while the International Robotic Cystectomy Consortium (Hellenthal et al, 2010) reported a rate of 6.8% in 513 patients—1.5% for stage ≤pT2, 8.8% for pT3, and 39% for pT4. Further evaluation, beyond surrogates such as lymph node number and margin status, is necessary to assess the oncologic efficacy of the operation.
Yuh et al. (2009) prospectively analyzed the impact of robotic cystectomy on quality of life in 34 patients undergoing surgery. Despite a significant number (38%) requiring chemotherapy, quality of life as assessed by the Functional Assessment of Cancer Therapy-Bladder instrument showed improvements at 3 months after surgery and total scores at 6 months exceeding preoperative scores.
Kauffman et al (2010) characterized the complications in 79 consecutive patients undergoing robotic radical cystectomy. Within 90 days of surgery, 49% experienced a complication of which 79% were low grade including infectious (41%) or gastrointestinal (27%). Sixteen percent of patients had a high-grade complication and were significantly associated with age older than 65 years, operative blood loss ≥500 mL, and intravenous fluids >5 L. These compare favorably with open radical cystectomy. Other studies suggest that advantages of the robotic approach include reduced blood loss, lower transfusion rate, shorter hospital stay, and earlier resumption of regular diet (Wang et al, 2008).