Management after a positive fecal immunochemical test and a nonexplanatory colonoscopy: a scoping review and practical decision framework

Key Takeaways for GI Nurses

• A positive fecal immunochemical test (FIT) followed by a colonoscopy that finds no cancer or advanced neoplasia — termed a "nonexplanatory colonoscopy" — is a common but poorly standardized clinical scenario that nursing staff will encounter regularly in FIT-based screening programs.
• This scoping review found wide variation in how "nonexplanatory colonoscopy" is defined across studies and policies, which has direct implications for how nurses document findings, communicate results to patients, and support scheduling of follow-up care.
• Colonoscopy quality metrics (e.g., bowel prep adequacy, cecal intubation, withdrawal time, adenoma detection) are central to determining whether a colonoscopy truly explains a positive FIT — reinforcing the nurse's role in optimizing prep education and periprocedural quality assurance.
• Patients with a nonexplanatory colonoscopy may still carry residual CRC risk and require individualized guidance on extracolonic evaluation and re-entry into screening, meaning nurses are often the first point of contact for patient questions and anxiety about "what happens next."

Clinical Relevance

For endoscopy nurses, this review highlights a gap that is felt acutely in day-to-day practice: patients often leave the endoscopy suite believing a "clear" colonoscopy after a positive FIT means the concern is resolved, when in fact the evidence base shows this population may still carry meaningful residual risk. Nurses play a pivotal role in pre- and post-procedure counseling, and understanding that "nonexplanatory colonoscopy" is an emerging, standardized concept — rather than simply a negative or normal result — allows for more accurate patient education. This is especially important when patients ask why further testing (such as extracolonic evaluation) might still be recommended despite a seemingly reassuring colonoscopy.

The review's emphasis on colonoscopy quality as a determinant of whether a study is truly "explanatory" reinforces the value of nursing contributions to procedural quality — including bowel preparation teaching, monitoring withdrawal times, and supporting documentation of cecal intubation and lesion detection. Units may need to revisit internal protocols for flagging cases where quality metrics were suboptimal, since these cases are more likely to fall into the "nonexplanatory" category requiring additional workup or earlier re-screening rather than routine-interval follow-up. Nurse-led tracking and recall systems could be strengthened to ensure these patients are not lost to follow-up, particularly given the review's finding that management and screening re-entry pathways are inconsistently defined across programs and policies.

From a professional development standpoint, this review signals an area ripe for standardized protocols and nurse-driven patient navigation. As screening programs increasingly rely on FIT as a first-line modality, endoscopy and GI nursing teams will be expected to help operationalize whatever consensus definitions and decision frameworks emerge from this evidence. Nurses involved in quality improvement, patient navigation, or screening program coordination should anticipate future guideline updates and consider how current documentation and communication practices align with the "nonexplanatory colonoscopy" concept, particularly regarding extracolonic evaluation referrals and appropriate screening re-entry intervals.

Bottom Line

When a colonoscopy after a positive FIT doesn't clearly explain the positive result, it should not automatically be treated as a reassuring "all clear" — GI nurses should recognize this as a distinct clinical category with variably defined but potentially important residual CRC risk, and should ensure these patients receive clear communication, quality-assured procedures, and reliable follow-up rather than being routed back into standard screening intervals by default.