Target biopsy using magnifying endoscopy in clinical management of gastric mucosa-associated lymphoid tissue lymphoma

Background and Aim: We have reported the characteristics of magnified endoscopic images of gastric mucosa‐associated lymphoid tissue (MALT) lymphoma before and after treatment. In this study, we investigated the diagnostic efficacy of magnified endoscopic images for target biopsy and evaluation of clinical remission. Methods: Twenty‐one patients diagnosed with localized gastric MALT lymphoma were enrolled. Magnified endoscopy was performed prior to treatment and at a mean period of 1.8 months (1–6 months) after therapy (Helicobacter pylori eradication in 19 patients and radiation therapy in two patients). Microstructural pattern and abnormal vessels in the lesions were assessed, and corpus mucosa without lymphoma was divided into H. pylori‐negative mucosa and H. pylori‐positive mucosa. Biopsy was the gold standard in this study. Results: Nonstructural areas with abnormal vessels were observed in all patients before treatment. Fifteen patients achieved pathological complete remission. Disappearance of nonstructural areas and abnormal vessels after therapy was associated with pathological remission. Sensitivities of these findings for diagnosis were 76.9% and 85.7%, respectively, and the specificities were 87.5% and 85.7%, respectively. H. pylori eradication therapy was invalid in three patients with H. pylori‐negative mucosa in magnified images. Conclusions: Magnifying endoscopy may be useful for target biopsy of superficial gastric MALT lymphoma in clinical management.