Abstract
We report two cases of small intestinal GIST causing gastrointestinal bleeding. Case 1: An 80-year-old man presented with tarry stools. A barium roentogenography and abdominal CT examination revealed a submucosal tumor in the jejunum, 10cm away from Treitz's ligament. We suspected that the tumor was causing gastrointestinal bleeding and operated. The histopathological diagnosis of the tumor was a low-grade malignant GIST;immunohistochemically, a tendency toward smooth muscle cell differentiation was observed. Case 2: A 73-year-old man presented with melena. An abdominal CT revealed an encapsulated tumor connecting with the small intestinal wall. A gastrointestinal scintigram demonstrated bleeding in the small intestine, and surgery was performed. A histopathological diagnosis of malignant GIST was made;immunohistochemically, a tendency toward neural cell differentiation was observed. Only 9 cases of small intestinal GIST have been reported in the Japanese literature, including the present cases. Of these 9 cases, 6 were malignant or suspected to be malignant. Small intestinal GIST should be recognized as a high risk group of malignancy requiring careful follow-up after operation.
