Abstract
A previously healthy 25-year-old man, with multiple cafe au lait spots, presented with vomiting and a sudden onset of abdominal pain. Ultrasound examination and a CT scan showed a 6×7 cm tumor in the pelvic cavity. At laparotomy, the tumor, which protruded from the subserosa of the jejunum, 20cm on the anal side from Treitz's ligament, was excised. The tumor was well encapsulated but partly ruptured and bleeding. Further inspection revealed three other tumors 0.5cm in diameter, located in the jejunum, 60, 70 and 100cm apart from Treitz's ligament. Histologically, the main tumor was composed of spindle-shaped cells with an interweaving bundle pattern. The three small tumors showed the same histological findings. Immunohistochemically, the tumor cells were partly positive for S-100 protein and for NSE, but negative for desmin and for smooth muscle actin. From the above evidence the tumor was diagnosed as a gastrointestinal stromal tumor (GIST), neural type, low grade malignant.
