[Aneurysmal bone cyst of the cranial base treated by partial resection and calcitonin injection. A case report].

STUDY DESIGN: First published report of a cranial aneurysmal bone cyst (ABC) treated successfully with intralesional injection of calcitonin.

OBJECTIVES: To describe a safe and effective treatment method for ABCs of the cranial base.

SUMMARY OF BACKGROUND DATA: ABC is a rare form of dystrophic pseudotumor. Less than 100 cases involving the skull have been reported in the literature, most of them localised in the cranial vault. Cranial base locations are rare and difficult to treat. We selected this treatment after a very rapid recurrence of the lesion following a partial resection. Method. - After a partial resection of a 10 cm petro-occipital ABC that encased the vertebral artery and the lower cranial nerves, an Ommaya reservoir was implanted with a catheter tip inside the ABC. Repeated intralesional injections of calcitonin were performed through the reservoir.

RESULTS: Shrinkage of the cyst occurred with disappearance of its heterogeneous cystic content and ossification of its walls. There was no complication and the lesion remains quiescent at a 3 year follow-up.

CONCLUSION: We reviewed the pertinent literature concerning percutaneous treatment of ABC. The percutaneous intralesionnal injection of calcitonin was reported in the literature only in 3 publications reporting 9 cases that did not involve the skull. This treatment seems safe and effective, worthy in cranial base ABCs that are difficult to resect completely.