Gorham-Stout Disease (GSD) is a rare disease in which progressive bone destruction occurs due to the proliferation of lymphatic vessels inside the bones. The thin-walled vascular or lymphatic channels grow within the bone leading to absorption of the bone (osteolysis). The missing bone is replaced with more lymphatic vessels and/or fibrosis. The amount of damage to the cortex of the bone may distinguish GSD from GLA.
The disease may also involve other parts of the patient’s body and symptoms may resemble those of other Complex Lymphatic Anomalies due to the proliferation of lymphatic vessels.
Because of the loss of the affected bone, the condition has been referred to as disappearing bone disease, vanishing bone disease, and massive osteolysis. In medical terminology osteolysis means: bone (osteo) breaking down or destruction (lysis).
What causes GSD?
Bone mass and strength are obtained and maintained through a remarkable process of bone destruction and replacement that occurs at the cellular level throughout a person’s life. Cells called osteoclasts secrete enzymes that dissolve old bone, allowing another type of cells called osteoblasts to form new bone. Except in growing bone, the rate of breakdown equals the rate of building, thereby maintaining bone mass. In Gorham Stout Disease that process is clearly disrupted.
In 1954 Gorham and three others published a two case series, with a brief review of 16 similar cases from the medical literature, that advanced the hypothesis that angiomatosis (development of blood or lymphatic vessels) was responsible for this unusual form of massive osteolysis. Gorham and Stout found that lymph vessels always occupied space that normally would be filled with new bone and speculated that the presence of these extra vessels lead to chemical changes in the bone. We now know that the growth of lymph vessels inside a bone prevents osteoblasts from doing their work properly to form new bone. This results in the weakening of the bone.
Who has GSD?
Gorham Stout Disease is extremely rare and may occur in a patient at any age, though it is most often recognized in children and young adults. It strikes males and females of all races and exhibits no inheritance pattern. The medical literature contains case reports from every continent. Because it is so rare, and commonly misdiagnosed, it is not known exactly how many people are affected by this disease. The literature frequently cites that fewer than 200 cases have been reported, though there is consensus building that there are many more cases around the world than have been reported.