Elements of screening and early diagnosis of lower GI neoplastic lesions: an overview

Dobrow's 12 consolidated principles were applied to evaluate the extent to which colorectal cancer (CRC) screening programmes align with these established screening principles. The principles within the first domain – disease and conditions – are fully met. CRC represents a significant global public health burden with a well-understood natural history, including a long preclinical phase. These features make CRC suitable for population-based screening. Current guidelines recommend screening average-risk individuals, with starting ages as early as 45 years and stopping ages up to 85 years in some programs, although most programs target those aged 50–75 years. For Dobrow's second domain – test or intervention - we found that established CRC screening methods (faecal immunochemical testing (FIT), colonoscopy, and flexible sigmoidoscopy) have known and acceptable sensitivity and specificity. These tests have clear thresholds for interpretation and follow-up and are associated with reductions in both CRC incidence and mortality, confirming their clinical effectiveness in organised programmes. Dobrow's third domain - programme or system - addresses how screening programmes should be structured, implemented, and integrated into health systems. Unlike the other domains, this is fully achieved in only a small minority of programmes. While implementation may vary from country to country, the principles provide benchmarks for well-organised programmes. CRC screening is generally cost-effective and widely accepted by patients, providers, and society. Successful programmes require dedicated teams, infrastructure, and systems for coordination and quality assurance. Before implementation, a CRC screening initiative must meet, or have a clear plan to meet 12 principles. In summary, robust infrastructure and governance are essential for organised CRC screening programmes to align with the Dobrow principles and achieve long-term success.