Geography May Influence Colon Cancer Screening Rates

MONDAY, Jan. 10 (HealthDay News) — Race and ethnicity play major roles in whether people get screened for colon cancer in the United States, with minorities much less likely to undergo colonoscopies than white people. Now, a new study says another factor is at play: where people live.

Research by oncologist Dr. Thomas Semrad and colleagues at the University of California at Davis Cancer Center found that location makes a big difference in rates of colorectal screening for non-whites, although the same isn’t true for whites.

The study authors analyzed data regarding 53,990 people on Medicare who were aged 69 to 79. They were from 11 regions of the United States.

In all locations except Hawaii, whites were more likely than non-whites to be up-to-date on colorectal screening, meaning that they had had a colonoscopy or sigmoidoscopy within the prior five years or a fecal occult blood test within the past year.

In Hawaii, Asian-Pacific Islanders had the highest screening rates: More than half of them had been screened recently compared to just 38 percent of whites.

“This is a stunning finding,” said Semrad in a university news release. “Screening rates among Asians in Hawaii were the highest of any group in any cancer registry area, including whites.”

Semrad pointed out that gastrointestinal cancers are common among Japanese people, a fact that may boost awareness of the importance of screening in Hawaii, where Japanese culture is influential.

As for other minorities elsewhere in the United States, Semrad suspects that many of them may get medical care in practices that don’t provide colorectal cancer screening. They may also have less access to primary and specialized care.

“The next step is to look at different geographic areas to see what are the determinants for minorities in terms of getting screened,” Semrad said. “Are these culturally based? Are there problems with how health-care systems are set up? What are the barriers? If we can figure this out, we would have a target to improve some of these disparities.”

The study is published in the Jan. 10 online edition of the journal Cancer.

When analyzing the data, the researchers adjusted their figures to take into account for other factors that could affect regional screening differences, according to the news release.

More information

For more about colorectal cancer, visit the U.S. National Library of Medicine.