Abstract
A 74-years-old woman with neurofibromatosis type 1 was admitted to our hospital for liver injury. Abdominal computed tomography revealed multiple cystic tumors in the liver and a solid tumor on the second portion of the duodenum. Histological findings of the biopsied specimen of the duodenal tumor showed spindle shaped tumor cells, which were immunohistochemically positive for KIT, the duodenal tumor was diagnosed as gastrointestinal stromal tumor. On the other hand, the biopsied specimen of the liver tumor showed hepatocyte-like tumor cells, which were different from the duodenal tumor. However, hepatic tumor cells were also immunohistochemically positive for KIT, the hepatic tumors were diagnosed as liver metastasis arising from the duodenal gastrointestinal stromal tumor. For this case, it is interesting that pathological and radiological findings of the metastatic lesion were different from the primary lesion.
