Multiple gastrointestinale Stromatumoren bei Neurofibromatose Typ 1

□ Background: Gastrointestinal stromal tumors (GIST) are generally rare, but appear more frequently in patients with neurofibromatosis type 1. Mostly asymptomatic, GIST can also cause relevant clinical appearances such as gastrointestinal bleeding, obstruction, or invagination. In recent years, a significant expert knowledge was gained in biology and treatment of these tumors. □ Case Report: The case of a 50-year-old man with a history of neurofibromatosis type 1 and acute gastrointestinal bleeding is described. In the index upper endoscopy an ulcerated tumor of the proximal small bowel was found. The histopathologic examination showed a GIST. Segmental small bowel resection was carried out. Over the course of 1 year, there has been no evidence of a recurrence, metastases, or metachronous GIST.