People with Type 2 diabetes may need to be screened earlier for colorectal cancer than people without diabetes, according to a preliminary study presented at the 2012 Digestive Disease Week (DDW) conference held in San Diego.
Current recommendations from the US Preventive Services Task Force call for colorectal cancer screening with high-sensitivity fecal occult blood testing, sigmoidoscopy, or colonoscopy to begin at age 50 in people at normal risk of the condition and to continue until age 75. (The decision to screen beyond age 75 should be made on a case-by-case basis.) People at higher risk of colorectal cancer — such as African-Americans and those with a family history of the disease — are advised to begin screening earlier and may need to be screened more frequently. (Type 2 diabetes has been associated with a higher risk for colorectal cancer, but people with Type 2 are not presently considered to be among the official at-risk population.)
To determine whether Type 2 diabetes is associated with an increased risk of developing colorectal cancer at a younger age, researchers from Washington University in St. Louis, Missouri, looked at data from three groups — people ages 40–49 with diabetes, people ages 40–49 without diabetes, and people ages 50–59 without diabetes — who had had colonoscopies at their center from June 2005 to June 2011.
They found that the rate of detecting benign tumors in the group with diabetes was similar to that found in the age 50–59 group without diabetes, translating to a significantly higher rate of tumor detection in people 40–49 with diabetes than in people 40–49 without diabetes. “These patients appear to be at the same risk level as those ages 50 to 59,” noted researcher Hongha Vu, MD.
The researchers were quick to note that the study was limited by its retrospective nature (finding a suitable control group, for instance, can be difficult in this type of study). They further add that larger, prospective studies (which follow a group of individuals over a period of time) will be needed before any revisions are made to the current colorectal cancer screening recommendations.
To learn more about the study, read the article “Diabetics May Need Early Colon Cancer Screening” (free registration required). For more information about colorectal cancer screening methods, see this section on the Web site of the National Cancer Institute. And for more about colorectal cancer and diabetes, see the article “Preventing Colorectal Cancer” by certified diabetes educator Judy Giusti.