Imaging Findings :Eccentric lucent metaphyseal lesion that may extend to the immediate subarticular cortex of a bone but does not involve the joint. Expansion toward the shaft produces a well-demarcated lucency, often with cortical expansion but without a sclerotic shell or border. Typically involves the distal femur, proximal tibia, distal radius, or ulna.
Giant cell tumor of the distal femur. Typical eccentric lucent lesion in the metaphysis extends to the immediate subarticular cortex. The surrounding cortex, though thinned, remains intact.
Malignant giant cell tumor. The tumor has caused cortical disruption, extends outside the host bone, and has an illdefined margin.