A case presenting with painless progressive osteolysis at right frontal bone diagnosed with Gorham-Stout disease

Abstract

Gorham-Stout disease (GSD) is a rare disease characterized by progressive osteolysis with abnormal lymphovascular proliferation. We herein report a pediatric case of GSD presenting with progressive bone absorption of the skull without local symptoms. A three-year-old boy with no remarkable history had a depressive lesion of the forehead at the three-year medical checkup. The number of depressive lesions increased over the next seven months. Computed tomography (CT) of the head revealed osteolysis of the frontal bone without soft tissue involvement, osteosclerosis, or periosteal reaction. Magnetic resonance imaging (MRI) revealed multiple hyperintense lesions on T2 fat-suppression imaging of the skull, vertebrae, pelvis, and femur. GSD was diagnosed by confirming abnormal lymphovascular invasion in a bone biopsy of the occipital bone. Owing to the concomitant cerebrospinal fluid leak leading to Chiari malformation type I, sirolimus, an oral mammalian target of rapamycin inhibitor (mTOR), was initiated to avoid major neurological complications by spiral cord compression. At the 20-month follow-up, sirolimus achieved stability in all altered intensity lesions on MRI. Prompt and detailed radiological examinations are needed to differentiate GSD from other pediatric osteolytic diseases and to assess the risk of complications due to affected bone lesions.