SCREESCO Trial: Colonoscopy + FIT and Early CRC Detection? Nature Medicine | February 2026

The SCREESCO randomised controlled trial provides rare population-level evidence comparing primary colonoscopy, low-threshold faecal immunochemical testing (FIT), and usual care in colorectal cancer (CRC) screening. Over 278,000 Swedish adults aged 60 years were randomised and followed for nearly five years during the diagnostic phase.

During this early period, overall CRC incidence was similar between colonoscopy and usual care, and slightly lower in the FIT arm. However, both screening strategies detected significantly more stage I–II cancers compared with controls—particularly colonoscopy—suggesting a stage shift toward earlier diagnosis rather than immediate reduction in overall incidence.

Adverse events were modestly increased in the first year among screened participants, including gastrointestinal and cardiovascular events, but differences attenuated over time. Participation rates were 35% for colonoscopy and 55% for FIT, highlighting real-world uptake challenges.

These findings emphasise that the early benefit of CRC screening lies in increased detection of localised disease, while harms appear small and largely front-loaded. Long-term follow-up will determine whether this stage shift translates into reduced CRC mortality.

Clinical Implication: Both colonoscopy and FIT enhance early cancer detection, but participation, safety balance, and long-term mortality outcomes remain central to screening policy decisions.