Mazabraud Syndrome in the Context of McCune-Albright: Contribution of Magnetic Resonance Imaging

Abstract

Mazabraud Syndrome (MS) is a rare condition characterized by the association of fibrous dysplasia and intramuscular myxomas and may occur in the context of McCune-Albright Syndrome (MAS), a genetic disorder caused by postzygotic mutations in the GNAS1 gene. We present the case of a female patient with a prior diagnosis of MAS, with a history of multiple surgical interventions due to craniofacial involvement and a previous low-grade mandibular sarcoma. Recent imaging reassessment with magnetic resonance (MRI) imaging revealed polyostotic fibrous dysplasia involving long bones and craniofacial structures, associated with multiple intramuscular nodules showing typical features of myxomas, namely low signal intensity on T1-weighted images and marked hyperintensity on T2-weighted images. The imaging findings allowed the diagnosis of MS in the context of the underlying condition. MRI played a central role in the detection, characterization, and follow-up of the lesions, as well as in excluding features suggestive of malignant transformation. This case demonstrates the role of MRI in the clinical-imaging correlation of MS and MAS, reinforcing the need for continuous surveillance for the early detection of malignant degeneration.