Invasive bladder cancer is typically treated surgically with radical cystectomy, the removal of the urinary bladder. In a landmark study published in The Lancet, investigators found that robot-assisted cystectomy was non-inferior to open surgery based on post-operative progression-free survival (PFS).
The RAZOR study was a randomized, open-label, non-inferiority, phase 3 trial performed at 13 U.S. sites and enrolling 350 subjects. Patients were randomized 1:1 to receive either robot-assisted or open surgery, and were followed for two-year PFS (the primary endpoint), surgical complications and health-related quality of life. Two-year PFS was 72.3% in the robotic cystectomy group and 71.6% in the open cystectomy group, which indicated statistically significant non-inferiority (P=0.001). Adverse events were similar in both groups (101 [67%] of 150 patients in the robotic cystectomy group and 105 [69%] of 152 patients in the open cystectomy group, with the most common being urinary tract infection (53 [35%] in the robotic cystectomy group, compared to 39 [26%] in the open cystectomy group) and postoperative ileus (33 [22%] in the robotic cystectomy group, compared to 31 [20%] in the open cystectomy group). Notably, subjects in the robotic group also experienced lower rates of blood loss and blood transfusion rates and shorter hospital stays.
The study is significant for several reasons. As noted in a press release from the University of Miami, one of the investigational sites, there are more than 5,000 surgical robots installed worldwide, but the RAZOR was the first phase 3, multi-center randomized trial comparing outcomes from robotic to open procedures. Further, it demonstrated not only immediate non-inferiority (as measured by AEs and intra- and post-operative factors, such as blood loss and length of stay), but that cancer-related outcomes were the same at two years.