The much-disputed field of robot-assisted surgery took another blow this week when doctors from Memorial Sloan Kettering Cancer Center warned that the high-tech procedure may be no better than traditional surgery for patients with invasive bladder cancer.
Device maker Intuitive Surgical (NSDQ:ISRG), which manufactures the surgical robot used in the study, disputed the researchers’ conclusions, calling the study "grossly misleading" because all patients enrolled received open surgery, even the ones the in the robot-assisted surgery arm.
The researchers said in a letter to the editor of the New England Journal of Medicine that their study turned up no benefits to using the more-costly surgical robot in radical cystectomy procedures, the surgical removal of the bladder. The researchers reported similar rates of complications and similar hospital stays for patients who had part of their surgery done less invasively with the da Vinci robot compared with those that had open surgery for the entire procedure.
The study, which was cut short after enrolling 118 participants, may be a bit problematic since it’s difficult to determine whether surgical complications in the hybrid arm were associated with the robot or with the open portion of the surgery. Researchers randomized patients to receive the 1st part of their cystectomy with either the less invasive surgical robot or with open surgery. The 2nd part of the procedure, the urinary diversion, was conducted via open surgery for all patients, according to the study protocol.
The doctors reported with confidence that patients who received robot-assisted laparoscopic surgery for part of their procedure were no better off than those than had open surgeries, which require more extensive incisions.
"The confidence intervals argue against a large benefit of robotic techniques with respect to perioperative morbidity," the authors wrote in their letter to the NEJM. "These results highlight the need for randomized trials to inform the benefits and risks of new surgical technologies before widespread implementation."
Intuitive Surgical which has long been fighting negative press about its costly high-tech devices, responded that the study isn’t a true representation of robot-assisted surgery. The results are muddled, the company said, because the complications in both arms were likely associated with the open portions of each procedure.
"The issue here is that, as described in the randomized study, open procedures were actually compared with hybrid procedures (a mixture of robotic for part of the procedure and then open for another part of the procedure). The authors’ not- too-surprising conclusion is that there is no difference in complications between surgical types," a company spokesman told MassDevice.com today. "That is because the primary complications are from the portions of these procedures that are performed using an open technique – which is done in both arms of the study. In essence, this letter to the editor is comparing open surgical complications to open surgical complications with a robotic dissection, and then concludes they are the same."
Intuitive Surgical also noted a couple of other studies of robot-assisted cystectomies that have turned up more favorable results. A 2011 study concluded that, "Despite an increased materials cost, [robot-assisted laparoscopic radical cystectomy] can be more cost efficient than [open radical cystectomy] as a treatment for bladder cancer when the impact of complications are considered." A 2010 report concluded that robot-assisted surgery "compares favorably with the open approach in several perioperative parameters," although that study found no differences in overall complication rates or hospital stays.
The company also emphasized that the NEJM publication was a letter to the editor and not in itself a peer-reviewed article, but a NEJM spokesperson confirmed that the researchers’ data had been peer-reviewed, the Wall Street Journal reported.
Analyst Lawrence Keusch at Raymond James Equity Research warned against putting too much weight on the NEJM letter, cautioning that the study isn’t a definitive one for robot-assisted surgery and that cystectomies aren’t a big revenue stream for Intuitive Surgical.
"Both procedures that were compared involve a 2nd phase, in which open surgery is used to reconstruct the bladder, making it tough to delineate the source of complications (which often occur in the bladder reconstruction phase), thus the comparison is not truly robotic to open surgery," Keusch wrote in a note to investors. "Radical cystectomy is not a large volume procedure for Intuitive Surgical, and clearly not one of the major growth drivers for the company. In fact, the conclusion of the letter states that more randomized clinical trials need to be performed before new surgical techniques are used broadly, which seems pretty benign to us."
Any weakness in the stock that results from this study, Keusch added, may represent a good opportunity to buy shares. ISRG shares actually gained a few points today, trading at a 4.2% increase to $480.92 as of about 1:50 p.m. EST. The stock got a big boost after beating expectations for its 2nd quarter in financial results released earlier this week. ISRG shares have gained 23.2% over the last 5 days.
Intuitive Surgical has had its hands full battling skeptics of robot-assisted surgery, who have argued largely that the technology represents significant unnecessary costs without added benefit to patients. The company was recently the primary subject of a study warning that novel devices may harm patients when clinics lean on the technology rather than on proper training. Earlier this year the da Vinci system also became a poster child for over-priced U.S. healthcare, with Permanente Medical Group CEO Dr. Robert Pearl blaming surgical robots and other devices for "increasing prices for products that don’t add much value."