by Carla K. Johnson, AP

A new study suggests that a less-invasive keyhole surgery for prostate cancer may mean a higher risk for lasting incontinence and impotence when compared with traditional surgery.

For the study, appearing in Wednesday's Journal of the American Medical Association, researchers analyzed Medicare data for nearly 9,000 prostate cancer patients who had surgical treatment from 2003-07. Of those, 1,938 patients had minimally invasive surgery and 6,899 patients had standard surgery. The data did not indicate how many of the less invasive cases involved robotics.

The patients who had keyhole surgery left the hospital in two days, rather than three, on average. They also had lower rates of blood transfusions, breathing problems and internal scarring. There was no difference in the rate of additional cancer therapy down the road, suggesting the two techniques were about the same for cancer control.

But the men who had keyhole surgery were more likely to report complications in the first 30 days after surgery involving genital and urinary function. About five percent of the minimally invasive surgery patients, versus about two percent of the standard surgery patients had these complications. And after 18 months, they had more incontinence and erectile dysfunction.

One potential explanation is the lack of experience many surgeons have before attempting to implement robot-assisted surgeries. Previous research has shown doctors who perform the most surgeries get the best results.

Dr. Steve Freedland of Duke University School of Medicine in Durham, N.C., said he doubts the findings will dampen the enthusiasm for robotic surgery — he termed it “mass hysteria over new technology” — because surgeons will claim better-than-average results when they talk to men considering their options.

Freedland, who does prostate surgery, said the results just reinforce his decision to stick with traditional, open surgery. “One of the reasons why health care in this country is extremely expensive is because it's assumed that what's newest must be best,” Freedland said.

The researchers found that the less-invasive surgery was more popular among more affluent, highly-educated men. So it might be that those patients are more likely to seek help for urinary and sexual problems compared to men who had traditional surgery, said Dr. Ashutosh Tewari, director of the Prostate Cancer Institute at New York Presbyterian Hospital/Weill Cornell Medical Center.

Tewari, who receives research funding from Intuitive Surgical (makers of the highly-touted da Vinci system) and had no role in the study, faulted the research for lumping all minimally invasive surgeries together, both robotic and those using older laparoscopic techniques.

Ryan Rhodes, a spokesman for Intuitive Surgical, said there have been more than 800 previous studies on robot-assisted prostate surgery. “The overwhelming majority of these show superior results,” for cancer treatment, urinary continence and sexual function, Rhodes said in an e-mail.

Dr. Greg Zagaja of University of Chicago Medical Center, who does similar research but wasn't involved in the new study, said the Medicare billing codes don't necessarily represent the surgical outcomes. He noted there wasn't a difference in the rate of procedures for treating incontinence and sexual dysfunction between the two groups.

Zagaja said the best advice for men is to ask how many robot-assisted surgeries a doctor has done.

Sources: JAMA: