Malignant granular cell tumor of the foot—multimodality imaging findings and literature review

We describe how the combination of imaging and histologic findings was essential in establishing a preoperative diagnosis of an extremely rare malignant granular cell tumor (GrCT) occurring in the lower extremity of a 17-year-old man. Magnetic resonance imaging demonstrated a large infiltrative tumor of heterogeneous intermediate signal intensity on both T1- and T2-weighted sequences. Subsequent computed tomography (CT) and fluorodeoxyglucose positron emission tomography CT scans of the patient revealed distant nodal and skeletal metastases.