Stromal tumor of the pancreas with expression of c-kit protein: report of a case.

We report on a case of a stromal tumor, similar to a gastrointestinal stromal tumor, originating from the pancreas. The patient was a 54-year-old woman, who was seen at the Kofu Municipal Hospital because of an abdominal tumor. On abdominal computed tomography and splenic arteriography, the tumor was detected in the pancreatic tail. The patient underwent distal pancreatectomy with splenectomy. Macroscopically, the cut surface of the tumor showed almost completely surrounded by the normal pancreatic tissue. Microscopically, the tumor composed of spindle-shaped cells that were immunoreactive for vimentin, CD34, and c-kit protein. Therefore, the tumor was diagnosed as a stromal tumor of the pancreas. The expression of c-kit protein suggests that this pancreatic stromal tumor may originate from primitive mesenchymal cells which can be a logical candidate for the origin of gastrointestinal stromal tumors and extra-gastrointestinal stromal tumors.