Fibrous Dysplasia and Intramuscular Myxomas

Description: Mazabraud's syndrome is a rare entity represented by the association of fibrous dysplasia and intramuscular myxomas. Their association was first reported in 1957 by A. Mazabraud, a French physican.[1] Mazabraud's syndrome does not appear to be hereditary and occurs mostly in women. The myxomas tend to develop and congregate around the thighs, buttocks, and shoulder regions. Their neoplastic nature has been questioned over time. Considering their tendency to group close to the affected segments of the bone involved by fibrous dysplasia, they are believed to be a reactive phenomenon due to local mechanical stress factors. Supporting this hypothesis is the fact that, histologically, they appear to be very close to synovial mucoid cysts occurring in stressed articulations.[2] Others hypothesize that they may be extraosseous manifestations of fibrous dysplasia.[3] When compared with isolated myxomas, their tendency to reoccur after removal is very low; however, note the postsurgical recurrence in this patient. As in our patient, the polyostotic form of fibrous dysplasia is predominant. Malignant transformation (eg, osteosarcoma, fibrosarcoma) in Mazabraud's syndrome has been reported, but the incidence remains very low.[2,4] For the myxomas, early surgery is usually advocated,[4] since involvement of neurovascular structures in advanced cases renders excisions more laborious. Appl Radiol 32(1):49-51, 2003