Mazabraud's syndrome: Report of its first incidence in the Middle East and a literature review

•This is the first case report of Mazabraud's Syndrome from Middle East.•Providing a literature review of the disease and its presentation.•Discussing GNAS1 gene involvement in fibrous dysplasia as well as other diseases.•Documenting the management plan done for the patient and the result of the follow up.

IntroductionMazabraud's syndrome, a rare benign disease with indolent course, is best described as an association between soft tissue myxoma and fibrous dysplasia of the bones. In this report, we describe the first case of this syndrome from Saudi Arabia.Case presentationA 24-year-old male in overall good health status, presented with progressive left knee swelling over 6 years with no other associated symptoms. The swelling measured 5 cm in diameter, with smooth surface, and soft palpable texture. Radiological examination followed by histopathological examination of the excised mass confirmed our diagnosis of Mazabraud's syndrome. The patient was closely followed up with systematic examination with no recurrence.DiscussionFibrous dysplasia, soft tissue myxoma and multiple endocrinological diseases like McCune-Albright syndrome characterize Mazabraud's syndrome. Furthermore, fibrous dysplasia is found to be associated with GNA1S gene mutation. Many patients can have asymptomatic course of the disease but may present with pathological fractures, pain, and limitation of movement when the myxoma is near the joints or just simple cosmetically disturbing swelling like in our case.ConclusionPatients with such presentation need to be investigated thoroughly to rule out associated diseases and to evaluate the extent of such pathology. The improvement of radiological modalities can help in narrowing the differential diagnosis and following the patient to early detect the recurrence or any malignant transformation of the condition.