Cleveland NK, et al. - Researchers performed this study to examine the peri-polyp biopsies of flat mucosa in patients with inflammatory bowel disease (IBD). Biopsies of the mucosa adjacent to discrete dysplastic polypoid lesions were found to be low yield in patients with IBD-associated colitis and did not predict findings in follow-up examinations. However, the grade of dysplasia of the polyp itself was predictive of subsequent advanced neoplasia.

Methods

• Endoscopic and pathologic findings were reviewed in IBD patients who had dysplastic polyps removed as well as biopsies of the adjacent flat mucosa.
• The risk for subsequent neoplasia was evaluated based on the presence or absence of dysplasia in the peri-polyp flat mucosa, and based on number and grade of index polypoid lesions.
• The researchers performed Kaplan-Meier survival analysis.

Results

• The researchers performed 102 colonoscopies in 56 IBD patients (68% UC), out of which 129 dysplastic polyps were resected.
• They performed 503 biopsies of the surrounding flat mucosa (mean 3.9 biopsies/polyp), among which 16 (3.2%) were dysplastic.
• In this study, median follow-up was 1.7 years (range 0.02-15 years) for 34 patients (21 UC), with 147 colonoscopies.
• During index colonoscopy, the presence of dysplasia in peri-polyp biopsies was not associated with risk of developing HGD or cancer (Pr Chi²=0.19).
• The size and number of dysplastic polyps were not predictive of neoplastic outcomes.
• However, the probability of developing subsequent advanced neoplasia for polypoid LGD was 18%, 29%, and 40% by 1, 3, and 5 years, respectively, and for polypoid HGD was 50%, 60%, and 70% by 1, 3, and 5 years, respectively (HR=7.0, standard error 4.8).