Primary aneurysmal bone cyst of the scapula in adult patient: two case reports and a review of the literature.

Aneurysmal bone cyst (ABC) is a rare, benign but locally aggresive bone tumor of unknown origin tumor. It commonly affects children and usually occurs at the metaphysis of long bones. Scapula is a very rare location and ABCs of the scapula have been sparsely described in the literature. Differential diagnosis can be challenging as it shares common radiological and clinicopathological features with other benign and malignant bone tumors. The degree of diagnostic difficulty increases even more when an unusual tumor site has to be taken into account. Here, we describe rare and challenging cases of a primary ABC located at the scapula that was surgically treated. This is the first case report of ABC involving the scapula in adult patient.