Abstract
An 83-year-old woman sought consultation with a chief complaint of abdominal mass, abdominal pain, and fever. Palpation revealed a tender tumor the size of a child's head, left of the abdominal midline. A huge tumor with a maximum diameter of 20 cm was observed in the peritoneal cavity on abdominal contrast-enhanced computed tomography. The tumor was continuous with the gastric fundus, and was twisted at the pedicle. She underwent surgery because of exacerbation of abdominal pain observed after hospitalization. Laparotomy revealed a huge tumor with a smooth surface and pale brown coloration that was growing in the omental bursa. The tumor had been growing from the gastric fundus in the vicinity of the upper pole of the spleen. The tumor showed torsion of 360° around the base. Torsion was released and the gastric fundus, including the tumor base, was resected with an automatic suturing device. The resected specimen was a huge cystic tumor, and the lumen was filled with old blood-like liquid. Hematoxylin and eosin staining showed a solid portion containing a bundle-shaped outgrowth of spindle cells. This portion was positive for KIT and CD34, and gastrointestinal stromal tumor (GIST) was diagnosed. This is a very rare condition, but with huge gastric GIST involving abdominal pain, it is necessary to consider not only rupture and bleeding, but also pedicle torsion.
