COLO-COHORT (Colorectal Cancer Cohort) Study

This study is building a large observational database (cohort) of people undergoing colonoscopy, to better understand the risk factors, early detection, and natural history of colorectal cancer. It includes both people who have cancer detected and those who don't. **You may be eligible if...** - You are 30 years or older and can give informed consent - You are attending for a colonoscopy (through cancer screening, NHS referral, surveillance, or for symptoms like rectal bleeding or iron deficiency anemia) - OR you are a first-degree relative of someone with colorectal cancer (for a separate cohort) **You may NOT be eligible if...** - You have a known inflammatory bowel disease (Crohn's or ulcerative colitis) - You have a hereditary colon cancer syndrome (e.g., Lynch syndrome, familial adenomatous polyposis) - You have previously had colorectal cancer Talk to your doctor to see if this trial is right for you.