case_images: PMC7314643_01
case_images: Ultrasound demonstration of the tumor. (A) Contrast-enhanced ultrasound image with size measurement as 5.0 cm at 19 s post contrast administration. (B) The relationship of the stomach and the tumor. Intact five layers of the stomach wall between the stomach and the tumor were indicated as: 1 M - superficial mucosal layer (hyperechoic), 2 MM - muscularis mucosal layer (hypoechoic), 3 SM - submucosal layer (hyperechoic), 4 PM - muscularis proper layer (hypoechoic), and 5 S - serosa (hyperechoic).
case_images: OTT-13-5831-g0001.jpg
case_images: PMC7314643_01_OTT-13-5831-g0001.jpg
case_images: F0001
case_images: Notably, gastric tissue adjacent to the tumor showed an intact structure of five layers of the stomach wall (Figure 1).
case_images: Preoperative CT investigation with (A) non-enhanced, (B) arterial phase, (C) venous phase, and (D) delayed phase images.
case_images: OTT-13-5831-g0002.jpg
case_images: PMC7314643_01_OTT-13-5831-g0002.jpg
case_images: F0002
case_images: On the contrary, a contrasted computed tomography (CT) was unable to rule out that the tumor was originated from the stomach wall due to tight tumor-stomach adjacency (Figure 2).
case_images: Preoperative MR investigation with (A) T1 weighted, (B) T2 weighted, (C) arterial phase images, and (D) diffusion-weighted imaging.
case_images: OTT-13-5831-g0003.jpg
case_images: PMC7314643_01_OTT-13-5831-g0003.jpg
case_images: F0003
case_images: Further magnetic resonance imaging (MRI) suggested that the tumor was close to the stomach wall with gastric mucosa uninvolved (Figure 3).
case_images: Results of pathology analysis. (A) An overview of histology by H&E stain. Zone A indicates the area composed of abundant spindle cells. Zone B indicates the area with loose structure and paranuclear vacuolization. Zone C indicates spindles cells with nuclear arrangement of the palisades. (B) Immunohistochemistry analyses showing expression of CD117, DOG-1, S100, Ki67, SMA, CKpan, p53, and CD34. (C) Pathological analysis of the relationship between the gastric wall layers and the GIST tumor.
case_images: OTT-13-5831-g0004.jpg
case_images: PMC7314643_01_OTT-13-5831-g0004.jpg
case_images: F0004
case_images: Immunohistochemistry results also supported the characteristic marker expression as gastric stromal tumor, including positive CD117, positive DOG-1, negative S100, 5% positive Ki67, negative SMA, negative CKpan, 8% positive p53, and positive CD34 (Figure 4).