Before his handlers took back what the actor had divulged, Michael Douglas touched off a media and medical sensation last June when he announced he had contracted throat cancer as a result, years earlier, of oral sex. Inadvertently, he inspired a teachable moment for a persistent problem — the sometimes highly disparate rates of cancer among racial and ethnic groups. But this disparity was a mirror image of the usual: Head and neck cancers rank among the rare cancers that afflict white Americans more often than any other demographic group.
The explanation is historical — and scintillating. This form of cancer is most often caused by the human papillomavirus, or HPV, which is transmitted by oral sex. In the wake of the sexual revolution of the 1960s, according to the Centers for Disease Control and Prevention, whites took to oral sex earlier and more enthusiastically than Americans in other racial and ethnic groups. That, explains Otis Brawley, the American Cancer Society's chief medical officer, is why white Americans now in their 50s and 60s are suffering disproportionately from head and neck cancers.
But there's something even more revealing in Douglas's tale: His cancer (at the base of his tongue, as it turned out) is in remission, and he expects to survive. While whites account for 85 percent of the nation's cases of head and neck cancer, they die of it no more often than African-Americans do. The reason: earlier diagnosis and better medical care. Head and neck cancers, particularly those caused by HPV, are highly survivable when they're caught in time.
These disparities won't be easy to erase, in part because they may be behavioral in origin. In the 1990s, for instance, black men were nearly 40 percent more likely to die of lung cancer than white men — and sooner. The average black victim had smoked for 30 "pack-years," compared with 50 pack-years for whites. Why the higher fatality rate? The answer was discovered in 1998, buried in tobacco-industry documents released as part of the mega-settlement between state attorneys general and cigarette companies: Lower-income smokers smoke differently than those with more money. They don't talk as much while they puff or let their cigarettes burn as long between drags. Wealthier smokers are less efficient, to their medical benefit. This research finding discredited the theory that the difference was genetic.
As Michael Douglas has learned, behavioral and cultural differences can work in minorities' favor. For decades, Latinos and Asian-Americans have been diagnosed far less often with several common cancers, including those of the lung, breast, and prostate. This has been particularly true for immigrants, regardless of income — largely because of diet and exercise habits, cancer researchers say. But in subsequent, presumably more assimilated generations, these advantages shrink.
Or consider the advantage that black and Latino women hold in sidestepping "estrogen-sensitive" breast cancer, the most common form of the disease. The cancer strikes less often among women who don't smoke, first give birth before age 30, and avoid hormone-replacement therapy at menopause. White women have been disadvantaged on all counts.
Yet white women fare better with the less common but more aggressive "triple-negative" breast cancer. African-American women develop this cancer twice as often as white women do and are 40 percent more likely to die of breast cancer in either form. Indeed, among all categories of Americans, black women are the likeliest to die of cancer of any sort — mainly, Brawley says, because of whites' greater access to medical care.
In Chicago, for example, all of the mammography machines able to detect smaller tumors and growths in dense, harder-to-analyze breast tissue — which is more common among black women — were outside the city line and hard to reach by public transportation, according to a Sinai Urban Health Institute study in 2012. Among women in metropolitan Chicago diagnosed with breast cancer between 2005 and 2007, 38 percent of African-Americans died within five years, compared with 23 percent of whites.
Latinas suffer the most from cervical cancer, which is ordinarily linked to HPV. In the United States from 2006 to 2010, 10.9 out of 100,000 Latinas fell victim, compared with 9.6 blacks, 7.9 whites, and 6.6 Asian-Americans. The reason, researchers say, is that many Latinas avoid regular gynecological screening that might detect cervical cancer or its precursors, partly from embarrassment but even more from lack of health care.
How might the United States reduce these disparities in cancer? There may be a lesson in the earlier experience with measles. In the late 1980s and early 1990s, an outbreak caused nearly 200 deaths across the country, mostly among children who hadn't been immunized. The result, in 1994, was the federal Vaccines for Children program, which mandates inoculations and covers the vaccination costs for the poor and uninsured. Today, vaccination rates for measles among poor children nearly match those for kids in wealthier households — between 90 percent and 93 percent in every racial and ethnic group.
"This may not be what some people want to hear," said Anna Kirkland, a University of Michigan political scientist who is an expert on public resistance to vaccines. "We use the two strongest tools that we have as a society. We mandate vaccination, then we cover the cost — and you basically eliminate disparities."