Colonoscopy screening markedly reduces the occurrence of colon carcinomas and carcinoma-related death: a closed cohort study

Gastrointest Endosc. 2012 Jul;76(1):110-7. doi: 10.1016/j.gie.2012.02.040. Epub 2012 Apr 11.


Background: Colonoscopy with a possible polypectomy is an efficient and preferred screening method to reduce the incidence of colorectal cancer (CRC). However, critics argue that, to date, a reduction of incidence and mortality from CRC has not been demonstrated in a population-based setting.

Objective: To compare the incidence of and mortality from CRC among individuals screened by colonoscopy and non-screened individuals.

Design: A closed cohort study.

Setting: Population-based setting in a precisely defined area with a low level of population migration.

Patients: This study involved 1912 screened and 20,774 control participants.

Intervention: CRC cases in this closed cohort study were prospectively collected during the screening period of 1 year and the follow-up period of 6 years.

Main outcome measurements: Follow-up data were corrected for negligible migration balance in the area. Tumor characteristics and risk or protective factors, age and sex, participation in general health screening examinations, history of CRC in a first-degree relative, smoking status, body mass index, frequency of sports activity, eating habits, and patients' professions were recorded.

Results: Overall cancer incidence was significantly lower in the screened group compared with the non-screened group (adjusted odds ratio [OR] 0.31; 95% confidence interval [CI], 0.16-0.59; P < .001). Colon cancer-associated mortality also was clearly lower (adjusted OR 0.12; 95% CI, 0.01-0.93; P = .04). Risk factors such as lifestyle, smoking, and body mass index as well as family history were similar in both groups. Blue-collar workers had a higher incidence of CRC compared with professionals. The risk factors for CRC were a positive family history and smoking.

Limitations: Number and ethnicity of the participants, non-randomized study.

Conclusion: Colonoscopy with polypectomy significantly reduces CRC incidence and cancer-related mortality in the general population.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoma / diagnosis*
  • Adenoma / epidemiology*
  • Adenoma / surgery
  • Aged
  • Aged, 80 and over
  • Carcinoma / epidemiology*
  • Carcinoma / mortality
  • Carcinoma / prevention & control
  • Cohort Studies
  • Colonic Neoplasms / diagnosis*
  • Colonic Neoplasms / epidemiology*
  • Colonic Neoplasms / mortality
  • Colonic Neoplasms / surgery
  • Colonic Polyps / diagnosis
  • Colonic Polyps / epidemiology
  • Colonic Polyps / surgery
  • Colonoscopy*
  • Confidence Intervals
  • Early Detection of Cancer
  • Female
  • Humans
  • Incidence
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Occupations / statistics & numerical data
  • Odds Ratio
  • Prospective Studies
  • Risk Factors
  • Smoking / epidemiology
  • Switzerland / epidemiology