A Primary Extragonadal Teratoma of the Proximal Humerus

A extragonadal malignant teratoma of the extremity is a rare pheonemenon. We describe a extremely rare case of malignant teratoma of the left proximal humerus in a 14-yr-old female. Radiologic evaluations, including magnetic resonance imaging, suggested a malignant bone tumor, but a pathological examination revealed an immature bony teratoma. Bone scintigraphy and positron emission tomography computed tomography scan showed increased uptake of proximal humerus but no other abnormal lesion.