Undetected Dysplasia at Colectomy in Patients With Inflammatory Bowel Diseases. What Are We Missing?

Background and aims: Patients with inflammatory bowel disease (IBD) have a higher risk of developing colorectal dysplasia and colorectal cancer compared to the general population. Although the use of surveillance protocols has improved the ability to detect dysplasia, some lesions are still missed at colonoscopy. This study aims to determine the rate of dysplastic lesions that are undetected at colonoscopies in IBD patients undergoing colectomy and to identify factors associated with missed dysplasia.

Methods: Patients who had received a total or subtotal colectomy at Mayo Clinic (Rochester, Minnesota), between January 2003 and December 2022, and had a complete colonoscopy within 5 years before surgery were retrospectively enrolled. Data abstracted included demographic information, disease-related data, colonoscopy and pathology reports, and surgery pathology reports. Colonoscopy and surgery findings were compared, and patients were divided into 3 groups: no dysplasia at both, detected dysplasia, and undetected dysplasia.

Results: Among 1320 IBD patients undergoing colectomy, 5.4% had undetected dysplastic lesions identified only at surgery. Factors independently associated with dysplasia detection were endoscopic remission or mild endoscopic disease activity (odds ratio [OR], 2.326; P = .0081; 95% CI, 1.246-4.342), prior dysplasia detection (OR, 1.876; P = .0491; 95% CI, 1.002-3.511), colonoscopy performed for surveillance (OR, 2.380; P = .0048; 95% CI, 1.302-4.350), and longer disease duration at surgery (OR, 1.039; P = .0085; 95% CI, 1.010-1.070).

Conclusions: Clinicians should be aware of the risk of missing dysplastic lesions, especially when endoscopic disease activity is moderate/severe, and not only for longstanding disease. Efforts should be made to obtain endoscopic remission to make the "invisible" visible.