Abstract
THE late William Dock, M.D., was reported to have advised medical students that "the most important thing to remember about rare diseases is that they are rare," and certainly such a statement is applicable to bone tumors. A comprehensive survey of the Swedish population for the years 1958 to 1968 showed a yearly incidence for osteosarcoma (the most common malignant tumor of bone) of 2.83 cases per million people.1 For chondrosarcoma, the incidence was 2.26 cases, for Ewing's tumor 0.87 and for giant-cell tumor of bone 0.39 cases per million. If one extrapolates these data to the United States, it . . .