NDBE: Nondysplastic Barrett's Esophagus
NDBE stands for nondysplastic Barrett's esophagus, which represents Barrett's esophagus without any evidence of dysplasia on histologic examination. 1
Definition and Classification
NDBE is the baseline histologic category in the Barrett's esophagus dysplasia grading system, defined by the presence of specialized intestinal metaplasia in the esophagus without cellular changes indicating dysplasia. 1 This classification is used in pathology reporting and staging systems for esophageal adenocarcinoma depth of invasion, where NDBE corresponds to the M1 level in both the Westerterp and Vieth-Stolte classification systems. 1
Clinical Significance and Progression Risk
The progression rate from NDBE to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) is low, ranging from 0.21% to 0.68% per year. 2, 3, 4
Key Risk Data:
- Overall annual progression rate to HGD/EAC: 0.27-0.68% per year 3, 4
- Annual progression rate to EAC alone: 0.21-0.57% per year 2, 4
- Five-year cancer-free survival: 98.6% 4
- Ten-year cancer-free survival: 97.1% 4
The risk decreases further with persistent NDBE over time—each additional year of progression-free follow-up reduces the incidence of HGD or EAC by 14%. 3 After two consecutive endoscopies showing NDBE, the progression rate drops to 0.55 per 100 person-years. 3
Surveillance Recommendations
Patients with NDBE should undergo surveillance endoscopy every 3 to 5 years. 1 This interval is based on the low progression risk and allows gastroenterologists flexibility to individualize based on segment length, with longer intervals appropriate for segments less than 3 cm. 1
Important Surveillance Considerations:
- Shorter Barrett's segments (<6 cm) have lower progression rates (0.09%/year) compared to longer segments (≥6 cm at 0.65%/year) 4
- The Seattle biopsy protocol should be followed: four-quadrant biopsies at 1-2 cm intervals along the entire Barrett's segment, plus targeted biopsies of visible lesions 5
- Only 15.9% of patients receive appropriate surveillance intervals in practice, with 37.9% being over-surveilled 6
Risk Stratification Tools
Tissue systems pathology assays (Tissue Cypher) may be utilized for risk stratification of patients with NDBE. 1 This assay quantifies 9 protein-based biomarkers along with nuclear morphology and tissue architecture, providing a numeric score from 1 to 10 that corresponds to progression risk. 1
Assay Performance:
- High-risk scores are associated with a 4.7-fold increased risk of progression and an annual progression rate of 6.9% (similar to low-grade dysplasia) 1, 7
- Sensitivity: 30.4% for single biopsy level, increasing to 50% with multiple spatial levels 1, 7
- Specificity: 95% 1, 7
- High-risk scores are strong independent predictors for progression (OR 14.2; 95% CI 5-39) 1
Management Essentials
All patients with NDBE should be placed on at least daily proton pump inhibitor (PPI) therapy. 1 PPI therapy is associated with a 71% reduction in the risk of HGD or EAC (adjusted OR 0.29; 95% CI 0.12-0.79). 1 Higher doses should be considered for symptom control or in patients undergoing endoscopic eradication therapy. 1
Common Pitfalls:
- Nearly 20% of endoscopies fail to adhere to the Seattle protocol, with adherence decreasing as Barrett's length increases 5
- Biopsies obtained during active esophagitis require repeat endoscopy after 8 weeks of twice-daily PPI therapy to confirm findings 1, 5
- Expert pathology review is critical given significant interobserver variability in dysplasia interpretation 1