"People who are poor - frequently Hispanic, African American or black, and Medicaid patients - tend to get what is considered to be less high-quality care than those who are middle class and wealthy," said Dr. Otis Brawley, chief medical and scientific officer of the American Cancer Society.

But Brawley, who wasn't involved in the new study, also said there is no evidence that removing a prostate with a robot is better than the old-fashioned way, with "open" surgery that requires an incision across a man's stomach.

Those are two of several treatment options available for prostate cancer, including radiation as well as active surveillance, also known as watchful waiting.

The American Cancer Society estimates approximately 250,000 men were diagnosed with prostate cancer in 2012, and about 28,000 died from it.

Despite a lack of evidence showing its superiority, robot-assisted prostate removal has become the predominant method since being approved by the U.S. Food and Drug Administration in 2000, according to the researchers, led by Dr. Simon Kim at the Mayo Clinic in Rochester, Minnesota.

Robotic surgical tools allow doctors to operate through small incisions with the aid of a tiny video camera, an approach that is considered less invasive but also tends to be more expensive.

Kim and his colleagues write in The Journal of Urology that evidence does exist to show that black patients are already less likely to get radiation or to have their prostates removed, but there is less data on whether they and other minorities have equal access to robot-assisted prostate removal.

For the study, Kim's group used two national databases to compare the differences between the approximately 20,500 cancer patients who had their prostates removed at hospitals offering robotic surgery, and the 9,500 who had their surgery at hospitals without robots between 2006 and 2008.

Overall, the researchers found, the proportion of all prostate removals shifted from about 56 percent taking place at hospitals with robots in 2006 to 76 percent in 2008.

They also found that hospitals offering robotic surgery removed more than four times the number of prostates as other hospitals during that time.

That's important because hospitals that remove more prostates tend to report better patient outcomes after surgery.

In addition, black patients were 19 percent less likely to have their surgery at a hospital using robots compared to white patients, and Hispanic patients were 23 percent less likely.

Medicaid patients were also 30 percent less likely to go to a hospital offering robotic surgery, compared to patients with private insurance.

Dr. Michael Barry, who was not involved in the new research but has studied prostate cancer treatment and outcomes, pointed out that the new work shows a gap in who is able to access the hospitals that perform the greatest number of prostate removals.

"The issue here is not access to robot (surgery) but high-volume hospitals," said Barry, a clinical professor of medicine at Boston's Harvard Medical School.

The study authors, who were not available for comment by press time, similarly conclude that gaps in access to robotic surgery hospitals may also indicate limited access to high-volume hospitals.

"More effective health care policies focusing on incentives to provide better access for minorities or for patients primarily insured by Medicaid may reduce disparities in access to high volume hospitals with robotic surgery," they write.

SOURCE: bit.ly/ZcKqmd The Journal of Urology, online December 18, 2012.

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