Gastrointestinal stromal tumour of the duodenum in a 7-year-old boy.

We report a 7-year-old boy presenting with an acute upper gastrointestinal (GI) haemorrhage subsequently diagnosed to have a very rare duodenal gastrointestinal stromal tumour (GIST). Endoscopy, pertechnetate and red cell scans were negative. Abdominal US detected a 17-mm mass lesion of the third part of the duodenum. This was confirmed on CT and shown to be hypervascular on selective angiography. At laparotomy, a 20-mm submucosal duodenal lesion was found associated with mucosal ulceration. Immunohistochemical analysis revealed it to be positive for CD117 (c-KIT protein) consistent with a GIST. We emphasize the importance of a thorough abdominal US examination in children with GI haemorrhage and the consideration of GIST in the diagnosis after the common causes have been excluded.