A CASE OF GASTROINTESTINAL STROMAL TUMOR WITH AN EXTRAGASTRIC PEDUNCULATED GROWTH

Abstract

A 63-year-old woman was admitted for resection of an 8-cm abdominal tumor touching the corpus of the stomach that had been detected by computed tomography. Gastroscopy revealed no remarkable findings, but endoscopic ultrasonography showed a submucosal tumor in an extragastric tract, at the greater curvature of the posterior gastric corpus. Laparotomy revealed the tumor to be located in the lesser peritoneal sac. As the tumor appeared to be connected with the posterior wall of the gastric corpus by a thin pedicle, 5 mm in diameter, it was resected together with a pedunculated lesion of the stomach during a partial gastrectomy. Hematoxylin-eosin staining of the histological specimen revealed round-like or spindle-shaped cells and very few mitotic figures per high power field. An immunohistochemical study showed that the tumor was positive for CD34, c-kit and smooth muscle actin but negative for S-100. Therefore, the tumor was diagnosed as a low-grade malignant gastrointestinal stromal tumor of the stomach.