Figure 1

Histopathological findings in duodenal gastrointestinal stromal tumors. (a) 61 year old woman without recurrence post-operatively. The tumor, size 33 mm, consists of spindle cells with a fascicular arrangement. Skeinoid fibers (SkF, *) are seen between the spindle cells (hematoxylin and eosin stain). (b) and (c) 61 year old woman without tumor recurrence post-operatively. The tumor size was 25 mm. Periodic Acid-Schiff reactivity is positive in SkF (b) and negative in the diastase digestion test (c). Scale bar = 100 μm in a, b, and c.