Gastrointestinal stromal tumor solitary distant recurrence in the left brachialis muscle

Figure 1 Magnetic resonance imaging of the left arm. A: Axial T2-weighted image showing a huge, ill-defined, high-signal-intensity mass (solid arrow); B: Coronal T2-weighted image showing a high-signal-intensity mass (dotted arrow).

Figure 2 Positron emission tomography-computed tomography. The scan shows an area of increased metabolic activity with irregular uptake (arrow) in the left brachialis muscle.

Figure 3 Histopathologic findings and immunohistochemical staining of the left brachialis muscle mass. A: Hematoxylin and eosin staining shows whorls of uniform spindle-shaped cells with elongated blunt nuclei and eosinophilic cytoplasm; B: Immunohistochemical staining for c-kit; C: Immunohistochemical staining for CD34 (magnification × 200).