Molecular stool screening for colorectal cancer

Using DNA markers may be beneficial, but large scale evaluation is needed

Colorectal cancer is the most common fatal malignancy among non-smokers in North America and Europe. Better tools are needed to improve the accuracy, compliance rates, safety, and affordability of screening. Stool testing has several important advantages over structural screening methods and warrants more investigation. Stool testing is non-invasive, avoids unpleasant cathartic preparation, can be performed on transported specimens without people having to visit their physicians, and, unlike sigmoidoscopy, reflects the state of the full length of the colorectum. Screening for stool markers that are more accurate than occult blood could substantially improve screening outcomes, and there is a strong biological rationale for targeting the DNA alterations that are exfoliated from neoplasms.

Faecal occult blood testing, used to screen for colorectal cancer for nearly three decades, continues to be the most widely used tool. Although controlled trials have shown that is of significant benefit, deaths from colorectal cancer have only been reduced by 15-33% after 10–14 years, and it has had no real impact on reducing the cumulative incidence of cancer.1^–3 These outcomes are …