To understand both the simplicity of disparities in health care and the complexity of eliminating them, consider this:

In the late 1970s and early '80s, black and white death rates for breast and colorectal cancer, two of the biggest killers, were more or less the same. They've been diverging ever since, with African Americans now one-third more likely than whites to die from either disease.

The reason is simple, said Otis W. Brawley, chief medical officer of the American Cancer Society: Detection and treatment dramatically improved about 30 years ago.

"When treatments didn't work, it didn't matter," he said. "We've gotten a lot better in medicine, is what happened."

And the complexity of eliminating the gap?

"As treatment becomes more and more effective and as technology becomes higher and higher tech" - and pricier and pricier - "the group of people who are less likely to get that treatment are the poor and the disenfranchised," Brawley said in an interview after speaking Thursday at a cancer disparities symposium that was ironically subtitled "We've Come So Far, But Where Are We Going?"

Disparities in health care have long befuddled physicians. Looking to their own futures, third-year residents in family and community medicine at Thomas Jefferson University Hospital asked a panel of physicians, researchers, and clergy to examine the issues.

Brawley, the keynote speaker, led off with a bit of context. "Race is a sociopolitical and not biological categorization," he said, that is periodically redefined by the U.S. Office of Management and Budget. Barack Obama was classified as white earlier in his life because the government then linked a person's race to his mother's.

There's no question that race and ethnicity play a big role in medical care. A 2000 study, for example, found that 7.5 percent of black women in Atlanta who were diagnosed with a localized, highly curable breast cancer did not get surgical removal of the tumor, compared with 2 percent of white women.

Masked by color, however, are cultural differences such as acceptence of treatment, lack of access, disparities in multiple conditions that make treatment more difficult, and, perhaps most important, socioeconomic status.

People with higher education have better outcomes. When researchers manipulated statistics to model what would happen if all African Americans with cancer died at the same rate as black college graduates did, more than 80 percent of the racial difference disappeared, Brawley said.

Ronald E. Myers, a medical sociologist at Jefferson who spoke on the panel, recalled that when doctors mailed out notices urging patients to get screened for colorectal cancer in the 1980s, whites responded much more strongly than blacks. When they got additional help, like someone walking them through how to set up a test, the rates evened out.

"It is the social part of health care that we often forget," Brawley said.