Aneurysmal bone cyst (ABC) secondary to Giant Cell Tumor of bone (GCT) is a rare lesion, of which the incidence is about to per 100,000 every year. There are only a few previous case reports, and most of them occur in the spine, long bones or flat bones. | Huge aneurysmal bone cyst secondary to giant cell tumor of the hand phalanx A case report and related literature