malignant bone cyst
malignant bone cystA highly nonspecific term for:
(1) Osteosarcoma, see there.
(2) A malignancy with cyst-like changes, which may be due to necrosis. (True cysts, as defined by histologic criteria, have an epithelial lining.)
(3) A near-extinct term for a bone cyst that is pernicious (i.e., not pathologically malignant). Any non-healing fracture with cyst-like changes accompanied by chronic osteomyelitis could be termed a malignant bone cysts.