[Gastrointestinal stromal tumor (GIST) of Duodenum: Case report].

Female of 64 years old, who two years ago was hospitalized in another institution for treatment of an abscess in the right liver lobe. During that hospitalization, it was found a duodenal tumor by tomography; however, no further studies or follow up on this finding was done. Prior to actual hospitalization, she was seen in a private clinic and treated with antibiotics for a suggestive"organized abscess" in the pancreatic head diagnosed by tomography. She presented with fever, abdominal pain and a palpable abdominal tumor in the right upper quadrant for a month. We realized a three-phase multislice spiral tomography with pancreatic curved reconstruction, which allowed to identified an ovoid tumor of 80 x 60 mm, with an area of central necrosis and intense contrast enhancement (arterial phase), located between the second and third duodenal portion, near the head of the pancreas. An upper endoscopy showed an extrinsic compression of the third duodenal portion. The patient underwent tumor resection without complication and the histologic diagnosis of the surgical specimen revealed a duodenal stromal tumor (GIST) with extraluminal transmural growth. We presented this case because of its unusual presentation of this tumor.