2007 Volume 40 Issue 2 Pages 209-214
We report a case of multiple gastrointestinal stromal tumors (GISTs) of the jejunum associated with von Recklinghausen's disease (R.s disease). A 54-year-old man with R.s disease had multiple neurofibromas and pigmented macules over the entire skin surface and was admitted to our hospital for anemia. Gastrointestinal fiberscopy revealed a hemorrhagic submucosal tumor on the third portion of the duodenum. At laparotomy a submucosal tumor was observed distal to the ligament of Treitz. and multiple submucosal tumors were found in the small intestine. We performed local resection and enucleations of the jejunum. These tumors were immunohistochemically positive for KIT and CD34, and negative for desmin and S100. However, genomic analysis of c-kit did not show any mutations. In sporadic GIST, 90% of the cases have been found to be caused by a gene mutation of c-kit and 5% by a gene mutation of PDGFR α. Recent studies have demonstrated the absence of the c-kit gene or a PDGFR α mutation in GISTs from NF1 patients. R.s disease is caused by a mutation of the NF1 gene on chromosome 17q11.2 that encodes the tumor suppressor gene neurofibromin. Disorders of neurofibromin due to mutations of NF1 cause tumorigenesis. We report multiple GISTs of the jejunum in a patient with R.s disease in whom no functional mutations were found in c-kit or PDGFR α.
