Could local deliver of bisphosphonates be a new therapeutic choice for Gorham-Stout syndrome?

The Gorham-Stout Syndrome is a rare condition in which spontaneous, progressive resorption of bone occurs. Even though the prognosis of the condition is generally considered to be good, Gorham-Stout syndrome can cause severe debilitation. In approximately 13% of recorded cases, death ensues. The treatment modalities for Gorham-Stout Syndrome include surgery, radiation therapy, anti-osteoclastic medications, however there is no known successful treatment. To date, the etiology of Gorham-Stout Syndrome is still controversial. However, general consensus on the importance of the derangement of osteoclastic activity and angiomatosis of blood vessels. Thus, local deliver of anti-osteoclastic and anti-angiogenic agents may be of great interest for the treatment of Gorham-Stout Syndrome. Bisphosphonates are potent in inhibiting osteoclast activity and promoting apoptosis, which has been widely used for the treatment of osteoporosis and osteolysis diseases and proved to be able to decrease the speed of bone destruction in Gorham-Stout Syndrome through systemic administration. In addition to its anti-osteolytic effect, bisphosphonates are currently shown to be capable of anti-angiogenesis and induction of apoptosis in tumor cells. Furthermore biocompatible calcium phosphate which is widely used for bone reconstruction in clinical has also been reported to be a suitable carrier for loading and releasing of bioactive bisphosphonates. Therefore, we hypothesis that local deliver of bisphosphonates by calcium phosphate may be a potential treatment of Gorham-Stout Syndrome.