Gorham disease, a rare condition of unknown etiology, is characterized histologically by bone disintegration and endothelial proliferation. We describe serial imaging findings, the treatment course, and radiotherapy response in a patient with pathologically confirmed Gorham disease involving the right mandible. Progressive mandibular resorption was managed initially with multiple surgical resections and reconstruction, followed by external-beam radiotherapy, which was an effective treatment method in this case. The patient's reconstructed mandible is functional and he is asymptomatic. Our literature review provides further insights regarding the clinical, radiologic, and pathologic behavior of this entity and examines the available treatment strategies.