Lifestyle Intervention Among Participants of the French Colorectal Cancer Screening Program (LIFE-SCREEN)

A pilot study was launched on March 23rd 2022 to assess the feasibility and acceptance of the LIFE-SCREEN study protocol. During the pilot study, participants were asked to complete several questionnaires about their lifestyle and health, while also having their anthropometrics measured and optional their blood taken and faecal sample collected. Evaluation questionnaires were completed by all participants and some participated in focus group meetings. Based upon this pilot study, it was decided in 2024 to drop the biospecimen collections due to feasibility issues. This RCT study launched in November 2024 will be a parallel, two-arm, randomized controlled trial (RCT) in individuals at higher risk of colorectal cancer (CRC), comparing an evidence-based diet and lifestyle advice intervention with 'usual care'. Participants will be recruited during CRC screening and will be included if they have a positive faecal immunochemical test (FIT) and are diagnosed with adenomas but are CRC negative during the colonoscopy. The advice provided will be developed based on the World Cancer Research Fund (WCRF) \& French National Cancer Institute (INCA) evidence-based diet and lifestyle recommendations using the habit-theory and will be delivered using multiple materials (e.g. leaflets, posters and digital information) by health professionals in hospitals based in the Rhone region, France. Invitation to participate in the trial will be performed by the gastroenterologist during the clinical visit to provide information on colonoscopy, but the delivery of the intervention and baseline measurement will happen two to three weeks after the colonoscopy. Data will be collected at baseline, 3, 6 and 12 months. At baseline, participants will be required to answer questionnaires on sociodemographic and medical history. At all aforementioned time points, online or paper-based questionnaires will be administered to collect information on diet and lifestyle behaviours, knowledge on healthy lifestyle, quality of life and medical therapy. Participants will also have their anthropometric measured during baseline and follow-up appointments. The primary outcome of this intervention will be adherence to target recommendations at 3 months and beyond. Univariate and multivariate statistical analyses as well as qualitative analyses will be performed. Providing lifestyle advice for cancer prevention at screening programs is a new field in public health that has the potential to be cost-effective, convenient, appealing and widereaching. It may also help to reach individuals at higher risk at a time-window when they adherence to cancer prevention recommendations, as well as on quality of life and body weight among individuals at higher risk of CRC.