label: Malignancy in Giant Cell Tumor of Bone
label_lc: malignancy in giant cell tumor of bone
description: A malignant tumor that arises from the bone.  It is characterized by the presence of an area of high grade sarcoma in an otherwise typical giant cell tumor (primary malignancy in giant cell tumor), or the presence of sarcoma in which the pre-existing giant cell tumor may or may not be apparent (secondary malignancy in giant cell tumor).