Colorectal cancer: prevention and early diagnosis

Colorectal cancer (CRC) is one of the leading causes of cancer deaths worldwide. This article reviews the aetiology and risk factors for CRC and focuses on strategies for prevention and early diagnosis. Prevention involves identifying and optimizing modifiable risk factors through public health awareness. Population screening for CRC is well established in clinical practice and increasing data support it as an effective method for early cancer detection and prevention through polypectomy, although multiple different appropriate faecal tests and endoscopic approaches exist and will be evaluated. Recent changes to UK screening programmes and advances in the understanding of molecular pathways for CRC development are highlighted and their respective roles for cancer prevention discussed. Endoscopic surveillance in the UK is currently offered to high-risk groups including those with multiple high-risk polyps and previous CRC after baseline colonoscopy, with recent changes to UK guidelines highlighted. Endoscopic surveillance is also offered to individuals with a genetic predisposition or long-standing inflammatory bowel disease. Finally, future directions in technology and research for prevention and early diagnosis of CRC, including those aided by artificial intelligence, are explored.