Chondrosarcoma, Grade II involving proximal femur in a 71 y/o male. The tumor is confined to the medullary cavity, with permeative growth around trabelcular bone, endosteal scalloping and an overlying periosteal reaction. Chondrosarcomas can occur virtually anywhere cartilage is found; however, two of the most commonly involved sites are long tubular bones and pelvis. Case produced with permission, courtesy of Dr. Frank Gaillard. Radiopaedia. Complete case is here.