[Malignant gastrointestinal stromal tumor (GIST) of the papilla vateri. A rare tumor entity].

We present the case report of a 68-year-old female patient who had a malignant gastrointestinal stromal tumor of the papilla of Vater. The abdominal CT showed a coin-shaped lesion in the liver (segment VIII). Intraoperative rapid histological examination detected an old parasitic hepatic cyst. To exclude metastasis, we performed duodenopancreatectomy with curative intention. The postoperative course was without complications and neither chemotherapy nor other adjunct treatment was necessary. Because of heterogeneity, the different localization, and in this case the rare localization, surgery of gastrointestinal stromal tumors is difficult. However, we adhered to oncological and therapeutic standards of surgery for papillary carcinoma. This case is discussed based on a review of the literature. However, until now there has been no case report of gastrointestinal stromal tumor of the papilla of Vater in the literature.