What is the recommended follow-up for a 51-year-old man with a history of positive multitarget stool DNA (MT-sDNA) test for Colorectal Cancer (CRC) screening, followed by a normal colonoscopy?

From the Guidelines

For a 51-year-old man with a positive multitarget stool DNA (MT-sDNA) test followed by a normal colonoscopy, the recommended follow-up is to repeat colorectal cancer screening with colonoscopy in 10 years. This recommendation follows standard colorectal cancer screening guidelines for average-risk individuals who have had a normal colonoscopy, as outlined in the most recent guidelines from the US Multi-Society Task Force on Colorectal Cancer 1. The positive MT-sDNA test that preceded the colonoscopy should be considered a false positive result since the colonoscopy was normal and found no concerning lesions. The colonoscopy is considered the gold standard diagnostic test, and its negative findings supersede the positive stool-based screening result.

Key Considerations

• The patient's normal colonoscopy indicates that there are no current lesions or abnormalities that require immediate attention or more frequent surveillance.
• The US Multi-Society Task Force on Colorectal Cancer recommends high-quality colonoscopy every 10 years or an annual FIT as first-tier options for screening of colorectal neoplasia, with a strong recommendation and moderate-quality evidence 1.
• The guidelines suggest that individuals who are up to date with screening and have negative prior screening tests, particularly high-quality colonoscopy, consider stopping screening at age 75 years or when life expectancy is less than 10 years, although this is a weak recommendation based on low-quality evidence 1.

Lifestyle Recommendations

• The patient should continue with routine age-appropriate cancer screenings.
• Maintaining healthy lifestyle habits is crucial, including:
  • Regular physical activity
  • A diet rich in fruits and vegetables
  • Limited red meat consumption
  • Avoidance of tobacco and excessive alcohol

Symptom Monitoring

• If the patient develops concerning symptoms such as rectal bleeding, change in bowel habits, unexplained weight loss, or abdominal pain before the next scheduled screening, he should seek medical attention promptly rather than waiting for the next screening interval.

From the Research

Colorectal Cancer Screening Recommendations

The user's question pertains to the best next step in future recommendations for CRC screening/surveillance for a 51-year-old man with a history of positive multitarget stool DNA (MT-sDNA) test, followed by a normal colonoscopy.

Analysis of Study Findings

• A study published in 2016 2 used clinical effectiveness modeling to project decreases in CRC incidence and related mortality associated with mt-sDNA screening. The study found that mt-sDNA testing at 3-year intervals reduced the CRC incidence by 57% and CRC mortality by 67%.
• Another study published in 2020 3 highlighted recent literature from post-market studies to provide an update on clinical use and utility of MT-sDNA testing. The study found that MT-sDNA appears to be attracting new patients to CRC screening, and patient adherence to diagnostic colonoscopy after a positive MT-sDNA test is high.
• A study published in 2022 4 covered current CRC screening guidelines and highlighted future blood-based and imaging-based options for screening. The study noted that non-invasive options will become increasingly important as the world attempts to recover from the COVID-19 pandemic and adapts to the start of CRC screening among people at average risk starting at age 45 years.
• A study published in 2022 5 reviewed the recently updated CRC screening recommendations and current and emerging testing options. The study noted that emerging CRC screening methods are being developed and evaluated, but additional large, multicenter clinical trials in diverse populations are needed to validate the diagnostic accuracy and generalizability of these new tests.
• A study published in 2025 6 evaluated the diagnostic performance of MT-sDNA testing and colonoscopy findings following a positive MT-sDNA testing result in a primary care setting. The study found that the majority of patients who completed MT-sDNA testing had a false positive result for advanced adenomas or CRC.

Recommendations for Future Screening

Based on the study findings, the best next step in future recommendations for CRC screening/surveillance for the 51-year-old man would be to:

• Repeat CRC screening in 3 years, as suggested by the 2016 study 2 and consistent with current guidelines.
• Consider alternative screening options, such as colonoscopy or other non-invasive tests, as highlighted in the 2022 studies 4, 5.
• Note that the 2025 study 6 raises questions about the effectiveness of screening based on MT-sDNA testing in an average risk population, but this finding is not directly relevant to the user's question.