What causes an aneurysmal bone cyst?
The cause of these tumors is unknown. However, they are believed to emerge in response to a disturbance of the rich capillary network in the host bone. Controversy exists as to whether or not aneurysmal bone cysts emerge secondary to a pre-existing tumor. In about half of all cases, a preexisting tumor, such as fibrous dysplasia, nonossifying fibroma, solitary bone cyst or osteosarcoma can be identified. Recently, abnormalities in the chromosomes (karyotype) of the tumor cells have been described, but the significance of these findings is unclear.
