Researchers say more study needed

Limitations to research on robotic surgery underlines the need for more large-scale, prospective studies that track patients afterward, doctors and researchers said.

While short-term benefits of robotic-assisted surgeries have been documented, including less blood loss versus open surgery and shorter length of hospital stays, the technology's superiority in long-term outcomes in not clear, they said.

Robotic surgeries first took off in the fields of urology and gynecology. Intuitive Surgical, which makes the da Vinci robot, claims that 85 percent of all prostate removal surgeries in the U.S. now are done on the da Vinci.

John Haller, a program director in the Division of Applied Science and Technology within a branch of the National Institutes of Health, said the technology caught on quickly.

"Part of it is the 'wow' factor of this technology, that every hospital wants to have the cutting-edge technology," he said.

The institute received $400 million in federal stimulus money to fund comparative effectiveness studies of medical technology, including robotic surgery.

Dr. Jim Hu, urologist at Brigham and Women's Hospital in Boston, said studies conducted on robotic prostatectomies thus far have largely focused on a single surgeon who had performed a high volume of the surgeries, skewing the results more positively. Dr. Hu recently led a large-scale study of Medicare patients who had undergone minimally invasive and open prostatectomies.

His study was one of the first to look at thousands of patients treated by both high-volume and low-volume surgeons, which he said is important since 70 percent of prostatectomies in the U.S. are done by low-volume surgeons.

The study, published in October in the Journal of the American Medical Association, actually found more diagnosed cases of erectile dysfunction and incontinence following minimally invasive prostatectomies. The study assumed most of the minimally invasive surgeries were robot-assisted, based on Intuitive Surgical's market share data.

Although his study was widely viewed as critical of robotic surgery, Dr. Hu, who has performed more than 1,000 robotic surgeries himself, said the take-away message should be that more research is needed to justify claims of robotic surgery's long-term benefits. Additionally, patient expectations must be realistic and above all, it is the experience of the surgeon with whatever technique he or she is using that matters most, he said.

"This isn't a clear-cut thing where you can say robotic is better than open surgery. The surgeon is really the most important thing," Dr. Hu said.

Dr. Lee Jackson, urological oncologist at Memorial, agrees that the most important factor in the outcome is surgeon experience, but he stressed that among surgeons adept at both open and robotic techniques, robot-assisted would practically always be preferred.

"There are authentic benefits," he said.