Robotic-assisted cystectomy demonstrated comparable 2-year PFS to open cystectomy among patients with bladder cancer, according to phase 3 results from the RAZOR trial.
Robotic-assisted surgery has served as an alternative minimally invasive surgical option for patients with cancer for more than a decade. However, only a few small, single-center, randomized trials have been performed, focusing only on perioperative recovery.
“No one had followed these patients over a period of time to find out if you are impacting their cancer outcomes with this robotic approach,” Dipen J. Parekh, MD, chair of urology and director of robotic surgery at University of Miami Miller School of Medicine, said in a press release. “We were able to prove unequivocally that we are not compromising patient outcomes by using robotic surgery.
“There are close to 5,000 robotic systems installed all over the world — each costs about $2 million — and yet until we did this study, there was not a single phase 3 multicenter randomized trial comparing this expensive new technology to the traditional open approach of doing surgeries,” Parekh added.
Radical cystectomy with pelvic lymphadenectomy and urinary diversions is standard surgical treatment for patients with invasive bladder cancer. Open cystectomy has risks, which include substantial blood loss, perioperative complications and mortality.
Although laparoscopic cystectomy is also a minimally invasive approach, robotic-assisted cystectomy offers advantages such as expanded views and mechanical wrists.
Researchers randomly assigned 350 patients to undergo robot-assisted radical cystectomy (n = 176) or open radical cystectomy with extracorporeal urinary diversion (n = 174). Patients had biopsy-proven clinical stage T1 to T4, N0 to N1, or M0 bladder cancer or refractory carcinoma in situ.
Researchers stratified patients based on type of urinary diversion, clinical T stage and ECOG performance status.
Two-year PFS served as the primary endpoint, with noninferiority classified as when the lower bound of the one-sided 97.5% CI for the treatment difference was more than 15 percentage points.
Ten percent of patients in the robotic cystectomy group did not undergo surgery, and 5% of patients had a different surgery than previously assigned. In the open cystectomy group, 12% did not undergo surgery, and 1% had robotic-assisted cystectomy instead of open cystectomy.
The per-protocol analysis set included 150 patients who underwent robotic-assisted cystectomy and 152 patients who underwent open cystectomy.
Two-year PFS was 72.3% (95% CI, 64.3-78.8) among patients in the robotic-assisted cystectomy group and 71.6% (95% CI, 63.6-78.2) among patients in the open cystectomy group, for a difference of 0.7% (95% CI, 9.6 to 10.9).
Researchers observed significantly less blood loss among patients in the robotic-assisted cystectomy group than the open cystectomy group (P < .0001). Also, fewer patients who underwent the robotic procedure required intraoperative blood transfusion (P = .0002) and postoperative blood transfusion (P = .0089).
The number of patients with local recurrence appeared similar between the groups (4% of robotic-assisted vs. 3% of cystectomy), as did local recurrence in the cystectomy bed (4% vs. 1%).
Poorer PFS was associated with increasing pathologic stage and positive surgical margins (P < .0001 for both).
Adverse events occurred among 67% of patients who received robotic-assisted cystectomy and 69% of those who underwent open cystectomy. Commonly observed adverse events included urinary tract infection (35% of robotic-assisted cystectomy vs. 26% of open cystectomy) and postoperative ileus (22% vs. 20%).
“There’s a steep cost to robotic technology, and there is a learning curve, so we need to build on this in terms of making rational, data-based decisions,” Parekh said.
“The patients will ask better questions, and the physicians, for the first time, will be able to answer these questions, based on data rather than based on intuition,” he added. “This is the highest level of data one can get.”
Although the results of the study were positive, favorable case selection may suggest the data should not be applied to all patients with bladder cancer, Roland Seiler, MD, and George N. Thalmann, MD, both from the department of urology at University of Bern, wrote in a related editorial.
“In the present study, case selection was highly suggestive; five to six patients per year per center were randomly assigned at high-volume centers,” they wrote. “Thus, the authors enrolled a cohort in which approximately 70% of patients had organ-confined disease, which is higher than that observed in most standard cystectomy series.”
Thus, that 4% of patients in the robot-assisted cystectomy group who had positive bladder margins and cystectomy bed recurrences had organ-confined disease needs to be considered when discussing this surgical approach, they added.
“Nevertheless, the authors should be congratulated for their effort and for showing that although robot-assisted radical cystectomy is probably more expensive than open cystectomy, when done by experienced surgeons and in selected cases, the approach is comparable to open radical cystectomy in terms of perioperative morbidity, quality of life and short-term oncological outcomes,” Seiler and Thalmann wrote. – by Melinda Stevens
Disclosures: Parekh reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures. Seiler and Thalmann report no relevant financial disclosures.