Invitation to Screening Colonoscopy in the Population at Familial Risk for Colorectal Cancer

Screening colonoscopy can lower the incidence of colorectal cancer (CRC), yet participation rates are low even in groups at high risk. The goal of this study was to double the rate of participation in screening colonoscopy among persons at familial risk and then to determine the frequency of neoplasia in this risk group.

In a nationwide, cluster-randomized, multicenter study, first-degree relatives (FDR) of patients with CRC across Germany received written informational materials concerning the familial risk of CRC, along with an invitation to undergo colonoscopy. Participants in the intervention group were additionally counseled by nurses over the telephone. The primary endpoint of the study was colonoscopy uptake within 30 days.

The participants' mean age was 50.8 years. The colonoscopy uptake rates were 99/125 (79%) in the intervention group and 97/136 (71%) in the control group (RR = 1.11; 95% confidence interval [0.97; 1.28]). A polypectomy was performed in 72 of 196 asymptomatic persons (37%). In 13 cases (7%), an advanced neoplasia was detected; two of these persons had colon cancer (stages T0 and T1). 42% of the participants expressed barriers against colonoscopy. 22 reported mild side effects; there were no serious side effects.

Additional counseling by nurses over the telephone does not increase the participation rate. Approaching patients who have CRC is an opportunity to increase the participation of their first-degree relatives in screening colonoscopy. The frequency of neoplasia that was found in this study underscores the need to screen relatives even before they reach the usual age threshold for screening.