Screening colonoscopy helps reduce CRC incidence, death

Use of screening colonoscopy leads to a robust reduction in colorectal cancer (CRC) incidence and mortality, according to a large prospective cohort study from Germany.

To examine the link between screening colonoscopy and overall and site-specific CRC incidence and mortality, the authors obtained information on use of screening colonoscopy and potential confounding factors at baseline in 2000–2002, updated at 2-, 5-, 8-, and 17-year follow-up, from 9,207 participants aged 50–75 years without CRC history in a statewide cohort study in Saarland, Germany.

Cox proportional hazards models with time-varying exposure information were used to assess covariate-adjusted associations of screening colonoscopy with CRC incidence and mortality, obtained through record linkage with the Saarland Cancer Registry and mortality statistics up to 2018.

Overall, 268 individuals were diagnosed with CRC and 98 died from the disease during a median follow-up of 17.2 years.

Screening colonoscopy correlated with strongly reduced CRC incidence (adjusted hazard ratio [aHR], 0.44, 95 percent confidence interval [CI], 0.33–0.57) and mortality (aHR, 0.34, 95 percent CI, 0.21–0.53). Reductions in incidence and mortality were more robust for distal (aHR, 0.36, 95 percent CI, 0.25–0.51 and aHR, 0.33, 95 percent CI, 0.19–0.59, respectively) than for proximal cancer (aHR, 0.69, 95 percent CI, 0.42–1.13 and aHR, 0.62, 95 percent CI, 0.26–1.45, respectively).

Notably, a strong reduction in mortality from proximal cancer was observed within 10 years after screening colonoscopy (aHR, 0.31, 95 percent CI, 0.10–0.96).

“A claimed advantage of colonoscopy over sigmoidoscopy in CRC screening is prevention of CRC not only in the distal colon and rectum but also in the proximal colon,” the authors said.