Spontaneous rapid regression of a juvenile primary aneurysmal bone cyst of the skull: A case report and literature review.

Aneurysmal bone cyst (ABC) is a benign lesion that often starts off the metaphysis of long bones and which, as it grows, may blow out bone. Only 3%-6% of cases are located in the skull. Spontaneous recovery has been reported. These cases occur more often in adults and in pelvic locations. Spontaneous regression at the skull level remains a very rare entity and few cases were described in the literature. Here, the authors report another case of spontaneous rapid regression of ABC of the skull in a 7-year-old boy revealed by gradually increasing painless hard swelling in the right frontal bone region with rapid spontaneous regression within 15 days. The authors will also proceed with an overview concerning this rare entity.