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- Discussion:
    - large radiolucent lesion surrounded by distinct margin of reactive bone;
    - often the lesion is eccentric;
    - cortical thinning, endosteal erosion, and trabecularization, or bony septation, of the cavity are associated findings;
           - lesion will aggressively destroy medullary and cortical bone;
    - scalloping and ridges in the wall of the tumor give it a "soap bubble" appearance on the roentgenogram