Primary mesenteric tumor with phenotypical features of gastrointestinal stromal tumors.

We report a case of a primary mesenteric tumor that was discovered in a 71-year-old man. Abdominal US accurately visualized the internal structure of the tumor but failed to determine the site of origin. Computed tomography suggested the mesenteric origin of the tumor before resection. The mass was removed and histopathological examination (including immunohistochemical and ultrastructural studies) was consistent with a primary gastrointestinal stromal tumor (GIST) of the mesentery, a very rare neoplasm scarcely reported in the radiology literature. Clinical, radiological, and pathological findings of this case are presented and the topic of primary mesenteric tumors with phenotypical features of GIST is reviewed.