Sporadic non-ampullary duodenal adenoma with low-grade dysplasia: Natural history and clinical management

Background and study aims Management strategies for sporadic non-ampullary duodenal adenoma with low-grade dysplasia (LGD) are not well established. This study aimed to analyze progression factors and determine suitable treatment strategies for LGD lesions. Patients and methods We retrospectively analyzed consecutive LGD lesions (n = 125) in patients followed up for ≥ 6 months (median, 45 months) and evaluated the changes in clinicopathological features during follow-up. All LGD lesions were classified into two groups: stable LGD (no increase or < 5 mm increase in tumor size, with unchanged histological dysplasia grade) and progressive LGD (≥ 5 mm increase in tumor size and/or progression to high-grade dysplasia or adenocarcinoma). Results Eighty-six LGD were classified as stable and 39 as progressive. Location on the oral side of the papilla of Vater, large initial tumor size ( ≥ 10 mm), macroscopically complex type, red color, and nodularity were significantly frequent in progressive LGD than in stable LGD. In multivariate analysis, large initial tumor size (odds ratio [OR], 10.2; 95 % confidence interval [CI], 3.3–32.1; P < 0.001) and location on the oral side of the papilla of Vater (OR: 1.8, 95 % CI: 1.4–12.5; P = 0.012) were significant factors for progression. Moreover, initial tumor size < 5 mm rarely progressed (0%–3.9 %); however, initial tumor size ≥ 20 mm and 10–19 mm located on the oral side of the papilla of Vater had a high-risk progression rate (75.0–85.7 %). Conclusions According to the risk stratification of progression factors by initial tumor size and location, we can determine suitable treatment indications for LGD lesions.