Fig. 1

a On admission contrast-enhanced CT showed a mass of 60 × 80 mm in diameter at the fornix of the stomach, which had intra-tumor heterogeneity with enhanced margin. Intra-tumoral extravasation of contrast agent was observed. b Twelve days after admission plain CT showed that the tumor grew to 65 × 90 mm in diameter. c On endoscopy, a submucosal bulge was identified with overlying normal mucosa on the anterior wall at the fornix of the stomach. d A 0–IIc ulcerative lesion surrounded by abnormal edge of converging folds, namely club-like thickening, was perceived at the lesser curvature of the gastric angle. e Endoscopic ultrasound demonstrated that the subepithelial cystic tumor containing hypoechoic papillary component arising from the 4th layer of the gastric wall, muscularis propria (arrow)