1. There now exists the basis for a new syndrome which is supported by a remarkable similarity of clinical and roentgenographic findings in twenty-four cases, and by an equally convincing similarity of the histological picture in eight of these, which we have personally studied.
2. However it is accomplished, the progressive osteolysis is always associated with an angiomatosis of blood and sometimes of lymphatic vessels, which seemingly are responsible for it.
3. A discussion of the possible mechanism involved is outside the province of this paper. Whether massive osteolysis occurs as the direct result of active hyperaemia, of mechanical causes, of slight changes in pH, or from other causes cannot be established at the present time.
Public Health Research Institute of the City of New York, Inc., and from the Laboratory of Surgical Pathology, Columbia University, College of Physicians and Surgeons, New York