The decision by Senator Kennedy to undergo brain surgery at Duke University Medical Center is illustrative of the strides some medical centers in the South have made in competing with hospitals in the Northeast as centers of excellence.

The proliferation of top-tier Southern hospitals has largely been driven by patient demand, and the result is often an increase in competition to recruit the best doctors and to offer the most cutting-edge treatments.

“The MD Andersons and the Sloan-Ketterings and the Dana-Farbers are the ones synonymous with cancer research, but so much research is being done in other places, obviously there are other places that will rise up in prestige and public awareness,” the senior vice president of communications at the American Hospital Association, Richard Wade, said.

Whereas choices were limited in the past, he said, nearly every state now has a major medical center that is doing “remarkable” cancer treatment. “Every one of these hospitals wants to be known as a national center of something,” he said.

Health care analysts said patient demand, and a growing recognition that providing cancer treatment is profitable for hospitals, has fueled a marketplace for treatment centers. “Cancer treatment is becoming more of a commodity,” an analyst at Moody’s Investors Service, Pamela Federbusch, said. “Patients are getting very educated and are willing to travel to seek out physicians with a particular expertise since the more experience tends to lead to better outcomes.”

In the case of Mr. Kennedy, the decision was reportedly based on the expertise of his neurosurgeon, Dr. Allan Friedman. It was also a boon to North Carolina, whose 7,000-acre Research Triangle Park is considered one of the country’s most well-known research and development sites.

“The fact that Duke is doing superior work at a high level is not a secret here,” the executive vice president and chief operating officer of the Research Triangle Regional Partnership, Ted Abernathy, said. Mr. Abernathy said the region has recruited top-notch researchers over the years in part because of the relatively low cost of living in the area, where the average price for a four-bedroom house is less than $300,000, he said.

According to a spokesman for the North Carolina Hospital Association, Don Dalton, the state’s hospitals routinely rank high on best hospitals lists, along with hospitals in Florida and Texas. “Obviously we’re pleased Senator Kennedy chose health care in North Carolina. It’s a point of pride for us,” he said.

Last year, the University of Texas MD Anderson Cancer Center ranked first on the magazine U.S. News and World Report’s list of the country’s best cancer hospitals. New York’s Memorial Sloan-Kettering Cancer Center ranked second, and Johns Hopkins Hospital ranked third. Other hospitals in the top 10 included the University of Washington Medical Center in Seattle; the University of Chicago Medical Center; UCLA Medical Center in Los Angeles; Duke University Medical Center, and Massachusetts General Hospital in Boston.

Given patient demand, geography plays a large role in the development of health care facilities, some said. “As the years passed, most of the academic institutions saw a need for establishing cancer centers at their institutions,” the executive director of the Association of American Cancer Institutes, which represents 92 hospitals and freestanding cancer centers, Barbara Duffy Stewart, said. She said there are about 30 institutions nationwide that are “emerging,” or seeking designation by the National Cancer Institute. The list includes Emory University; the University of Miami; Howard University; George Washington University; Loyola Cancer Center; the University of Kentucky, and the Nevada Cancer Institute. “It’s not as if they’re all in the Northeast by any means,” she said.

Doctors at some of those hospitals said patients flock to institutions that are doing cutting-edge research on their specific disease.

At Cedars-Sinai Medical Center, the chairman of neurosurgery, Dr. Keith Black, said patients have been attracted to the hospital’s brain cancer vaccine trials, which started about a decade ago. “We see patients now from around the world,” Dr. Black said. “As some of the newer and more advanced trials take place, given the severity of this disease, sometimes patients are attracted to clinical trials that are offering more hope and promise.”

At the same time, a generation of doctors and researchers who trained at East Coast institutions are branching out.

“Young people come along and they say, ‘The establishment is working in this direction, let’s try something new,'” the director of neurosurgery at Johns Hopkins Hospital, Dr. Henry Brem, said. He said 11 physicians who trained under him now direct brain tumor units at various hospitals nationwide. “The training and the NIH funding has led to another generation that’s spread out that’s not consolidated in places like Hopkins.”

Patient advocates said having more top-notch doctors improves patient care. Hospitals, in an effort to distinguish themselves, are developing programs specializing in certain aspects of care, and at least one byproduct is collaboration between facilities.

“It’s not as though one of two or three are better than the others,” Patricia Goldsmith, the executive vice president of the National Comprehensive Cancer Network, a network of the 21 leading cancer centers, said. “The sum of the parts is greater than the whole.”

Dr. Brem also downplayed competition, saying there is enough work to go around. “It’s a bad disease and we don’t have all the answers,” he said.