[Gastrointestinal stroma tumor].

Gastrointestinal stromal tumor (GIST) represents less than 3% of gastrointestinal malignancies. However, it is the most common mesenchymal tumor of the digestive tract. GIST is characterized by the expression tyrosine kinase CD117, which differentiates it from other mesenchymal tumors such as leiomyomas, leio-miosarcomas, leiomyoblastoma and neurogenic tumors that do not express this protein. 70-80% of the GIST are benign and located mostly in the stomach and small intestine (> 90%).They can also arise from any portion of the digestive tract, mesentery, omentum and retroperitoneum. Malignant GISTs are usually large (> 5 cm), with a high mitotic index, and it can metastasize to the liver and peritoneum. The treatment is surgical resection.Good results have been reported with tyrosine kinase inhibitor STI571. The treatment is the surgical resection; in cases of surgical resection tumors cannot do it, radiotherapy and chemotherapy is carried out. A 43 year-old patient is presented, admitted to present pain in the epigastrium, melena in an occasion. The ecography, CT scan, and laparoscopic view, showed a tumor in the second portion of the duodenum, approximately 10 cm size. Whipple's operation was carried out (cephalic pancreatoduodenectomy) with conservation of the pylorus (Traverso-Longmire), resecting the entirely tumor. Final results of pathological anatomy informed: fusocelular tumor of the gastrointestinal estroma (GIST of duodenal wall), with high potential of malignancy. Size of the tumor 9,5 cm, mitotic index of 9 for 50 HPF with high positive for CD117, CD34. Two years later of the intervention he presents a good evolution.