NCIt related terms : Juxtacortical osteosarcoma; Parosteal;
NCIt definition : A low grade malignant bone-forming mesenchymal neoplasm arising from the surface of
the bone. It usually affects the distal posterior femur, the proximal tibia, and proximal
humerus. Painless swelling is the usual clinical sign. Most patients are young adults
and the prognosis is usually excellent.;