Gastrointestinal stromal tumor with extensive lymphatic metastasis: a case report.

Gastrointestinal stromal tumor is a rare tumor which arises from the whole gastrointestinal tracts and most of it is detected in the stomach. It is uncommon with small intestine originated gastrointestinal stromal tumor and more uncommon with lymphatic metastasis. We experienced an unusual case of the small bowel gastrointestinal stromal tumor during experimental autopsy. Two primary tumors with central necrosis were detected in the ileum. The sizes of each tumor were 6.1×3.4×4.0 cm and 3.7×4.2×3.2 cm. There was extensive lymphatic metastasis on the greater omentum and mesenteric, iliac lymph nodes were also involved. With histologic findings, the eosinophilic spindle cells were densely distributed. Immunohistochemical findings were CD117 (-), CD34 (+), desmin (-), and S-100 protein (-). Therefore, we diagnosed the tumors as small bowel gastrointestinal stromal tumors with broad lymph node mestasis.