Long-term follow-up study of gastric intraepithelial neoplasias: Progression from low-grade dysplasia to invasive carcinoma

Background and study aims: A gastric intraepithelial neoplasia (IEN) is usually regarded as a precancerous lesion; however, the natural history of the gastric IEN has not been clarified. We aimed to evaluate the progression of dysplasia in gastric lENs. Patients and methods: As a retrospective study, we reviewed 26 gastric adenomas with low-grade dysplasia (LGD) and one with high-grade dysplasia (HGD) from 18 patients. The patients were followed up for a median of 66 months from 1996 to 2004 (mean 58 months, 20-112 months) in Kyungpook National University Hospital. The histological diagnosis was classified according to the Vienna classification. We reviewed clinical (age and sex), morphological (size, color, shape, location in stomach, surface nodularity, and presence of the erosion), and histological (histological diagnosis, infection with Helicobacter pylori, infiltration of inflammatory cells, atrophy, intestinal metaplasia, microscopic erosions, and glandular appearance) characteristics with regard to progression of dysplasia. Results: We found eight lENs of progressive dysplasia (29.6%). One IEN with HGD and three lENs with LGD progressed to invasive adenocarcinoma (category 5). Four gastric lENs with LGD progressed to HGD (category 4). The clinical, morphological, and histological characteristics did not reveal any distinguishable features for progressive dysplasia. Conclusion: For the potential risk of progressive dysplasia, gastric lENs should be treated actively using the recently advanced therapeutic endoscopic techniques, regardless of the degrees of dysplasia.