A CASE OF GASTROINTESTINAL STROMAL TUMOR OF THE SMALL INTESTINE WITH PERITONEAL DISSEMINATION TREATED BY STI571

Abstract

Recently, it has been reported that STI571 (imatinib) is effective to c-kit positive gastrointestinal stromal tumors (GIST). We experienced a good response of STI571 to GIST of the small intestine with peritoneal dissemination. A 76-year-old man was admitted to the hospital because of melena and anemia. Abdominal CT scan and small intestinal fluoroscopy demonstrated a mass 3cm in diameter on the jejunum. During surgery, we recognized an elastic hard mass at 60cm from the Treitz ligament and multiple elastic masses 5-10mm in diameter in the almost entire peritoneum. Intraoperative pathologic diagnosis was small intestinal GIST with peritoneal metastasis. We excised the jejunal mass which was the source of bleeding. The mass was smooth muscle type of GIST with c-kit positive and high grade of malignancy. After discharge, we talked with the patient and prescribed STI571 from 17^th postoperative week. The ascites decreased and a complete remission of peritoneal dissemination was attained.