Efficacy of a nationwide screening colonoscopy program for colorectal cancer

Background & aims: Screening colonoscopy examinations for colorectal cancer are offered in the United States and some European countries. Data on results and adverse effects of screening colonoscopy are limited. In autumn 2002, colonoscopy was introduced as part of a nationwide cancer screening program in Germany; it was offered to the general population for individuals 55 years of age or older. We collected and analyzed data from this program.

Methods: We performed a prospective cross-sectional study, collecting results from 2,821,392 screening colonoscopies performed at more than 2100 practices by highly qualified endoscopists in Germany from January 2003 to December 2008. Data on participation, colorectal adenoma and cancer detection, and complications were collected using standardized documentation forms. The data generated were centrally processed and evaluated.

Results: The cumulative participation rate was 17.2% of eligible women and 15.5% of eligible men 55-74 years old. The adenoma detection rate (ADR) was 19.4%, with a higher rate in men (25.8% vs 16.7% in women). Advanced adenomas were found in 6.4% of patients. Carcinomas were detected in 25,893 subjects (0.9%); most were of an early UICC stage (I, 47.3%; II, 22.3%; III, 20.7%; IV, 9.6%). The ADRs for gastroenterologists and nongastroenterologists were 25.1% and 22.3%, respectively (adjusted odds ratio, 1.18; 95% confidence interval, 1.16-1.21). The overall complication rate was 2.8/1000 colonoscopies, and the rate of serious complications was 0.58/1000 colonoscopies.

Conclusions: A nationwide colonoscopy screening program that uses highly qualified endoscopists can detect a significant number of adenomas and early-stage carcinomas. The ADR for gastroenterologists was higher than for nongastroenterologists.