Robotic Prostate Surgery: Too Much Too Fast?
In the console - the command center of a robotic surgery unit - the surgeons have a super-magnified, three-dimensional image of the patient's interior. The camera providing those images perches on the end of one of four long robotic arms inserted into the lower abdomen via small "keyhole" incisions only a few centimeters wide. The other three arms hold the tiny instruments the surgeons use to perform what is, in effect, laparoscopic surgery.
According to Intuitive Surgical, which manufactures the da Vinci, the only surgical robot cleared by the Food and Drug Administration (FDA), 390 facilities in North America now have a robotic surgical device. The FDA only cleared the device for radical prostatectomy in 2001, yet, according to Intuitive, it is now used in more than one in every three such procedures performed in the United States. In some facilities, the device is used far more often.
"We have decided that 90 percent of what we do with open surgery we can do better with the robot," says Dr. Mani Menon, director of the Henry Ford Health System's Vattikuti Urology Institute, and one of the earliest adopters of robotic prostatectomy.
The expanding popularity of robotic prostatectomy - as well as robotic gastric bypass, mitral valve repair, and hysterectomy to treat cervical and endometrial cancer, among other procedures - has been fueled largely by patient demand, says Dr. David Lee, a urologic surgeon at the University of Pennsylvania Medical Center, which has five robots.
Because it's minimally invasive and, so far, appears to offer "the same level of outcomes for important parameters," he says, "I think it's appealing for everybody."
Even with such rapid proliferation, some urologists and urologic surgeons note that a true benefit of robotic prostatectomy compared with open surgery has yet to be shown. That's a significant piece of missing data, they argue, particularly in the face of the da Vinci's cost: approximately $1.5 million, which includes annual maintenance fees and disposable equipment costs (but excludes the time and resources needed to train surgeons on its use). That combination, they say, suggests that it could be premature to widely embrace robotic surgery as the standard of care for radical prostatectomy.
Waiting on the Data
"You can really do a precise dissection around the prostate because of the built-in advantages the robot has," Dr. Lee says.
The benefits of robotic radical prostatectomy, explains Dr. Peter Pinto, a surgeon in NCI's Urologic Oncology Branch in the Center for Cancer Research (CCR), appear to be less postoperative pain, less blood loss, and faster return to regular activities and work.
And based on short-term results from published surgical "series," he continues, robotic radical prostatectomy may yield equivalent cancer control outcomes compared with open surgery. Generally speaking, that means the removal of the prostate without leaving any cancerous cells at the surgical "margin." However, because of the short time that surgical robots have been in use, reliable data on biochemical recurrence - life without the return of prostate cancer - another important oncologic measure, aren't available.
So-called functional outcomes, mainly return to continence without the need for protection from urinary leakage and the ability to gain an erection and have sexual intercourse, also appear to be equivalent in robotic procedures compared with open surgery, Dr. Pinto adds.
Because of his advanced training in minimally invasive surgery, Dr. Pinto tells his prostatectomy patients that, in his hands, they are likely to have the best outcome with a robotic procedure. Even so, he cautions, overall, "there are not enough long-term data to support that this approach is superior to open surgery. It's still too new to say that."
Drs. Lee and Menon believe the oncologic and urinary function outcomes data - much of which are still unpublished - are trending in favor of the surgical robot.
For sexual function, says Dr. Lee, "That may be an area where we do a little bit better with the robot."
Dr. Menon says he is still pulling together data on a large series of patients - more than 1,600 with 5 years of follow-up - that is looking especially promising in terms of biochemical recurrence rates.
"Normally, it would take 10 years to accumulate so many patients," he says. "But robotics has been so well accepted by patients that we've been able to get the series."
In terms of oncologic outcomes, comparing the robotic procedure with open surgery is complicated by the slow-developing nature of prostate cancer, which can take up to two decades to develop into full-blown disease. So the ultimate measure, survival rates, will not be available for some time.
Even then, says Dr. Yair Lotan, a urologist the University of Texas Southwestern Medical Center, there may not be much to see.
"The bottom line is that it's difficult to improve on what Patrick Walsh did," he says, referring to the Johns Hopkins researcher famous for pioneering the "nerve-sparing" radical prostatectomy, an open surgery approach that offers good oncologic outcomes while also limiting damage to the nerves that ride along the prostate and control urinary and erectile function. "A survival benefit will be difficult to demonstrate."
Dr. Lee argues, however, that robotic surgeons only need to demonstrate that the less-invasive robotic procedure generates equivalent, not superior, outcomes to justify its use.
Even if the robot does turn out to have equivalent or superior outcomes compared to open surgery, Dr. Pinto is concerned about two things: the burgeoning popularity of robotic surgery, particularly among younger surgeons, and the reliance on a computer system running the robot that can "crash" during a procedure, which has happened once to Dr. Pinto. In that case, he subsequently completed the surgery by hand, with laparoscopic techniques.
"Today, surgeons still learn the open approach during training. However, if the current trend toward robotic surgery continues, there may come a time when young surgeons never see an open case," he says. "Although a rare occurrence, what happens when the robot stops working during the surgery? Will they have the skill set to complete the procedure safely?
By Carmen Phillips