Impact of DietarY and LIfestyle Risk Factors on Colorectal Cancer Screening

The main purpose of our project is to construct a lifestyle score based on a short questionnaire easy to complete and to validate it among participants in mass screening for colorectal cancer in Maine and Loire department over the next 2 years (2012 and 2013). We will evaluate the ability of our score to identify subjects with colorectal cancer diagnosed by the screening procedure (Hemoccult II ®, and colonoscopy if the test result is positive). Colorectal cancer will be the primary outcome for the assessment of the score's performance. The secondary endpoint will focus on colorectal adenomas diagnosed by the same procedure. Our secondary objectives are to test a second weighting system, evaluate the benefit in terms of predictive performance to add to the lifestyle score other dietary factors among that have a probable link with the risk of colorectal cancer, determine the acceptability of the questionnaire and to estimate by a cost-utility analysis the impact of applying a strategy of targeted screening using the developed score.

Sex

All

Minimum age

50 Years

Maximum age

75 Years

Inclusion Criteria:

* All participants in the organized screening for colorectal cancer over the next 2 years in the Maine-et-Loire department.

Exclusion Criteria:

* Personal or family history of polyps or colorectal cancer
* Personal history of bowel disease that already implies a surveillance by colonoscopy (inflammatory bowel syndrome, HNPCC, FAP)
* Diseases with known genetic risk of developing colorectal cancer