Postoperative encapsulated hemoperitoneum in a patient with gastric stromal tumor treated by exposed endoscopic full-thickness resection: A case report

Figure 1 Preoperative endoscopic examination results. A: Endoscopic image showing a hemispherical protrusion, approximately 16 mm in diameter, located at the upper gastric curvature adjacent to the stomach fundus, with a smooth surface mucosa and poor mobility; B: Endoscopic ultrasound image showing a mass 19.3 mm × 16.1 mm in size, derived from the muscularis propria, which partly grew outside the cavity. The echo pattern of the mass was uniform and at a low level.

Figure 2 Abdominal computed tomography examination. A: Gastric computed tomography (CT) illustrated a well-demarcated mass, 16 mm × 15 mm in size, demonstrating mild enhancement, with an intact mucosal line; B: Abdominal CT revealed a large amount of encapsulated fluid and gas accumulation around the stomach.

Figure 3 Postoperative pathological examination results. A and B: The tumor was located in the muscularis propria and was a spindle cell tumor, arranged in a bundle-like interweaving pattern with mild nuclear atypia (H&E, original magnification × 100); C and D: Immunohistochemical staining of tumor cells showed diffuse positivity for CD117 (C) and DOG1 (D), which were diffusely expressed on the surface of cell membranes.