Black Americans are at higher risk for colon polyps

September 24, 2008

Black Americans have a higher occurrence of colon polyps, according to a new study. This is a significant finding considering the incidence of colon cancer among black men has increased and remained unchanged among black women during the last 20 years.

The article will be published in the Sept. 24, issue of JAMA (Journal of the American Medical Association).

The new study, led by David A. Lieberman, M.D., head of gastroenterology, Oregon Health & Science University School of Medicine and Portland VA Medical Center, measured the incidence and location of colon polyps that were more than 9 mm in diameter, about the size of a pencil eraser, in men and women of all age groups who had undergone colonoscopy screenings at 67 sites across the United States.

Lieberman and colleagues found that of 5,464 black patients and 80,061 white patients who had undergone a colonoscopy, 7.7 percent (422) black patients and 6.2 percent of white patients (4,964) had at least one or more polyps larger than 9 mm. Black men had a 16 percent greater chance of having polyps larger than 9 mm, while black women had a 62 percent greater chance.

"These data show that Blacks who receive screening are more likely to have serious polyps, compared to Whites, and are therefore likely to benefit from more intensive screening. Black men and women age 50 years and older should be strongly encouraged to receive colon cancer screening," said Lieberman, who also is co-director of the OHSU Digestive Health Center at the Center for Health & Healing and a member of the OHSU Cancer Institute.

According to the researchers, colorectal cancer prevalence and death are higher among black patients. Death rates for black men and women are 38 percent to 43 percent higher than for white men and women, and incidence rates are 15.5 percent to 23 percent higher in black individuals.

Lieberman and colleagues published the first large study using colonoscopy for colon cancer screening (New England Journal of Medicine, 2000), and demonstrated the limitations of other screening tests, such as fecal occult blood test and sigmoidoscopy (New England Journal of Medicine, 2001), and office fecal testing (Annals of Internal Medicine, 2005). Since these publications, colonoscopy has become the most commonly used colon screening test in the United States and has contributed to the reduction in both incidence and mortality during the past few years.

Source: Oregon Health & Science University