A 56-year-old man with a rectal gastrointestinal stromal tumor. A: Axial T1WI shows the lesion as a round, intraluminal, homogenous, hypointense mass with a sharp margin (arrow); B: It shows homogenous hyperintense on T2WI (arrow); C: Sagittal enhanced T1WI shows homogenous moderate enhancement (arrow); D: Photomicrograph shows fascicular proliferation of spindle-shaped tumor cells (hematoxylin and eosin, × 200); E: The tumor cells were strongly and diffusely positive for CD117 staining (immune-histochemistry, × 200).