No participants in a study of the German colonoscopy screening program who had a clear colonoscopy developed colorectal cancer almost twelve years after their exam.
Advanced adenomas were also reduced significantly.
Scientists at the German Cancer Research Center in Heidelberg compared a group of 553 people who had a negative screening colonoscopy to another group of 2701 who didn’t receive a colonoscopy.
After an average of 11.9 years, there were no colorectal cancers diagnosed in people with a negative colonoscopy compared to 8.4 in the group that weren’t screened.
Advanced adenomas — polyps most likely to become cancerous — were more than 52 percent lower 11 to 15 years later. Even after 16 years, risk of finding an advanced adenoma was reduced by more than 47 percent.
Statutory health insurance in Germany has offered free screening colonoscopies to people over 55 since 2002. Since that time over 1.8 million colonoscopy screenings have been done reaching about 40 percent of German women and 30 percent of men.
Hermann Brenner, MD, MPH and his colleagues concluded:
The low risk of CRC and advanced adenomas after a negative colonoscopy supports suggestions that screening intervals be extended to ≥10 years.