THE CHONDROMA in its pure form without any osseous cells may be one of the most troublesome of bone tumors. Because of its cellular nature, its occasional failure to be revealed in roentgenograms and its tendency to extend locally beyond borders which are at best not easily discerned on macroscopic inspection, it becomes a difficult tumor to handle surgically. Add to this the fact that at times some areas of these tumors may be undergoing malignant change while others appear benign and that there is a widespread belief that some of these tumors, apparently benign when first seen, may actually undergo malignant degeneration, and one has an even more serious problem.
Coley1 made a distinction in chondrosarcomas, classifying some as primary and others as secondary. The latter type "results from a malignant alteration in the cells of a cartilaginous exostosis, a central chondroma or rarely in a patient who