Family history and screening for colorectal cancer

African Americans have the highest colorectal cancer (CRC) incidence and death rates of all racial groups in the United States. The reason for this is thought to be multifactorial but remains poorly understood. Overall, African Americans have low rates of colorectal cancer screening compared to most other racial groups. Early detection is especially important for those with family histories of CRC who are at higher risk of developing the disease. Factors associated with CRC screening are not well understood for African Americans, both those with and without family histories of CRC.

To investigate the factors associated with risk-appropriate CRC screening, Kathleen Griffith, Ph.D., CRNP, of the Johns Hopkins University School of Nursing and colleagues at the University of Maryland Baltimore analyzed data from the 2002 Maryland Cancer Survey, a telephone survey of more than 5,000 Maryland residents, performed under the Maryland Cigarette Restitution Fund Program, to identify predictors of screening among African Americans.

The researchers' analyses revealed that for African Americans, regardless of family history, a health care provider's recommendation for colorectal cancer screening was strongly correlated with a higher likelihood of screening. Furthermore, individuals who were more physically active were also more likely to have been screened for colorectal cancer. Surprisingly, though, having a family history of colorectal cancer did not predict a higher likelihood of screening. In fact, the researchers found that African Americans with a family history were less likely to have received risk-appropriate screening than those without a family history. Family history of colorectal cancer is often associated with increased rates of screening in whites.

The authors say it is difficult to explain why a perception of increased risk, which is significantly higher in African Americans with a family history of CRC than in those without, did not translate into screening. Their findings suggest that other unknown or unmeasured factors may play a role is screening decisions. Additional studies to determine what those factors might be could lead to culturally tailored interventions designed to increase screening rates, which in turn could ultimately improve early detection and reduce colorectal cancer deaths in African Americans. "This study suggests that African Americans would benefit from a primary care approach that evaluates their risk factors for colorectal cancer, and provides corresponding recommendations for appropriate screening tests," the authors write.

Regular colorectal cancer screening is one of the most powerful weapons in preventing colorectal cancer. It can, in many cases, prevent colorectal cancer altogether. Experts estimate adherence to national screening guidelines could prevent up to eight in ten deaths from the disease. The American Cancer Society recommends that people at average risk begin screening for colorectal cancer at age 50. Colorectal cancer is the third most common cancer diagnosed in both men and women in the United States, as well as the third leading cause of cancer-related death among both men and women in the United States.

Source: American Cancer Society