Gorham-Stout disease (GSD) is rare, characterized by proliferation of vascular channels resulting in progressive distruction of bone. In the Rizzoli files we found 15 cases of GSD from 1968 to 2008. Two were excluded for insufficient documentation. For 13 cases clinical data, imaging and histology were analysed. Histopathologic features included benign vascular proliferation, vascular pattern of osteolytic angioma, fibro-connective tissue component and bony destruction. A final diagnosis was established based on clinical, radiological and histopathologic features.

Imaging included X-rays in 11 cases and CT or MRI in 5. All lesions were lytic, with associated sclerosis in two cases. There was one lesion only in 4 cases, multiple lesions in the same bone in 1 and multiple bones involved in 6. Primary sites were proximal femur in 7 cases, pelvis in 2, hip and knee, calcaneus, humerus and cervical spine in 1 case each. Two patients had no treatment, 2 conservative treatment (cast or brace), 5 surgery, 6 medical treatment (byphosphonates, calcitonin, zoledronic acid, interferon, steroids), 1 radiotherapy, 2 selective arterial embolization. Surgery consisted of internal fixation of pathologic fractures in 4 patients and reconstruction of the entire humerus with a double composite allograft in 1. Treatment was surgery only in 2 patients, medical treatment in 4 (1 also embolization), surgery and medical treatment in 2 (1 also embolization), radiotherapy only in 1, conservative treatment in 2. Four patients were lost at follow up. Mean follow up was 17 ys.(min 2, max 30) in 9 patients: 2 dead, 3 healed, 3 with stable disease, 1 alive with disease at 24 ys.

No conclusive treatment recommendations are possible; surgery is indicated in pathologic fractures or reconstruction of massively destroyed bones, medical treatment and selective embolization are helpful. In literature prosthetic reconstruction is preferred due to the risk of allografts resorption.