Malignant transformation of a non-osteogenic fibroma of bone

Jaffe and Lichtenstein (1942) were the first to recognise and describe the clinicopathological entity that they named "non-osteogenic fibroma of bone". Subsequently Hatcher (1945) renamed it "metaphyseal fibrous defect of bone". This lesion, under either or both of these names, has now, for the following reasons, generally gained acceptance as a clinical and pathological entity. (i) It is found almost exclusively in older children and adolescents and only rarely in adults. ; (ii) It affects the shafts of the long tubular bones in the metaphyseal region and bears a constant relation to the epiphysis. ; (iii) The radiological features are distinctive: it is radiolucent, loculated and eccentric in position. It lies in the long axis of the bone. ; (iv) The histological pattern is typical, with whorled bundles of connective-tissue spindle cells, scattered small multinucleated giant cells and variable amounts of haemosiderin and foam cells. There is no evidence of osteogenesis. ; (v) The lesion is usually self-healing and never undergoes malignant transformation.