A 51-year-old woman was admitted to our hospital because of tarry stools and dizziness. She had undergone investigation of anemia at another hospital previously, and endoscopy and biopsy had been performed a few days earlier. Endoscopy showed an elevated lesion 6 mm in size at the greater curvature of the middle body of the stomach. The surface of the lesion was covered with normal gastric mucosa and blood was leaking from the lesion center. Forty days later, the lesion had enlarged to 12 mm in size, now had redness at the surface and formed a polypoid lesion with a depression at the center. Magnifying endoscopy findings showed an unclear surface structure of the depression. To reduce the risk of re-bleeding and establish a diagnosis by total biopsy, endoscopic submucosal resection was subsequently performed. Histological examination revealed lobular growth of capillary vessels with hyperplasia of endothelial cells, and a diagnosis of pyogenic granuloma was made. Pyogenic granuloma is rare in the gastrointestinal tract and only seven cases have been reported in the gastric mucosa. Here, we report a case of pyogenic granuloma of the stomach with rapid change of form over a short period of observation.
