Cancer Interception: Targeting the Seeds Years Before a Tumor Forms

Scientists are pursuing 'cancer interception'—targeting cancer-causing processes long before tumors appear, using genetic clues, precancerous lesions, and multicancer early detection (MCED) blood tests that look for circulating tumor DNA. While promising for catching cancers earlier (notably colorectal cancer), MCEDs face challenges like missed cancers, false positives requiring follow-ups, cost, and ethical concerns around overdiagnosis and health inequities. Regulators and researchers aim to combine genetic, environmental, and MCED data to guide prevention in a safe, fair, and effective way, with UK plans to expand diagnostic testing as part of national cancer strategy.