Scientists are puzzling over a surprising increase in stomach cancer in young white adults, while rates in all other American adults have declined.
Chances for developing stomach cancer are still very low in young adults, but the incidence among 25- to 39-year-old whites nonetheless climbed by almost 70 percent in the past three decades, a study found.
National Cancer Institute researchers and colleagues examined new cases from 1977 to 2006 of cancer in the lower stomach, which can be caused by chronic infection with the common bacterium H. pylori. It also causes stomach ulcers.
The incidence rate for young white adults climbed from 0.54 per 200,000 to about 1 per 200,000.
Among white adults ages 25 to 84, the rate declined from almost 12 per 200,000 to 8 per 200,000. Among black adults, it declined from about 27 per 200,000 to 19 per 200,000.
Rates also declined for other races, which weren't specified.
The study appears in today's Journal of the American Medical Association.