Fibromyxoma of bone: a case report and review of the literature.

In this study, a case of fibromyxoma of the proximal femur in a 59-year old woman is reported. The classification of this rare bone tumour is still a matter of debate and some investigators have suggested that these lesions represent a degenerative form of fibrous dysplasia. Some authors make a further distinction between fibromyxoma and myxoma of bone. In a review of 23 cases of fibromyxoma and five cases of myxoma, no differences in clinical, radiographic and biologic behaviour between fibromyxoma and myxoma were found. Apart from the age at diagnosis, the most important difference between fibromyxoma and myxoma was the degree of myxoid matrix. Therefore, we suggest that extragnathic myxoma is a regressive variant of extragnathic fibromyxoma and should be termed as the same entity. In contrast to monostotic fibrous dysplasia fibromyxoma / myxoma often causes pain and presents as a Lodwick IC lesion with a soft tissue mass. Therefore, fibromyxoma / myxoma should be distinguished from fibrous dysplasia because of its different clinical and radiographic features.