Key Clinical Message
During endoscopy, a light purple flat lesion suddenly appeared at the antrum and the lesion disappeared subsequently. This is an unusual reversible color change that is associated with blood flow, and that must be differentiated from neoplasia.
A 63-year-old man with heart failure underwent esophagogastroduodenoscopy. The patient had not receivedHelicobacter pylori eradication therapy and results of serum antibody test were negative. Endoscopy revealed no gastric lesion upon initial scope insertion (Figure 1A ). During observation, an approximately 25-mm diameter, light-purple-colored flat lesion appeared at the antrum’s greater curvature (Figure 1B, 1C ). Magnifying narrow-band imaging revealed a regular microsurface and microvascular pattern (Figure 1D ). The lesion subsequently faded upon slight deflation of the stomach (Figure 1E ), but reappeared upon reinflation (Figure 1F ).
The lesion was well-demarcated and flat. Biopsies of both the lesion and surrounding mucosa were performed to rule out neoplasm. Hematoxylin-and-eosin-staining of the lesion revealed mostly normal fundic glands; however, the gland density and mucosal thickness were slightly decreased compared to the surrounding mucosa (Figure 2 ). CD31 staining revealed little remarkable findings of vascular density. Computed tomography revealed no masses compressing gastric walls. Although there have been previous reports on evaluation of gastric blood flow,1,2 investigations on real-time color changes in gastric lesions are rare. This study shows unusual reversible color change in a gastric lesion associated with slight blood flow changes and reflecting a small focal atrophic change which must be differentiated from neoplastic lesions.