Locally aggressive orbital giant cell reparative granuloma in an infant: case report and literature review.

Giant cell reparative granuloma (GCRG) is a non-neoplastic hyperplasia of bones that mostly happens in the mandible and maxilla in any age group but has a predilection for children and young adults. GCRGs that cause bone destruction are of very low frequency. Orbital-involved cases have been rarely reported since 1981, especially in children. We now report a 1-year-old girl with a rapidly enlarging post-traumatic orbital mass. CT scan and surgical resection showed a well-defined mass occupying the upper right orbit, causing bone destruction. Microscopically there was a proliferation of histocytes and some osteoclast-like multinucleated giant cells with hemosiderin, finally confirmed to be GCRG. 22 months' follow up showed no evidence of recurrence. This case suggests infant orbital GCRG can be locally aggressive.