Osteoclastoma of the orbit. Case report.

TUMOURS characterized by the presence of giant cells are not uncommonly seen in sections from orbital masses. The histologic appearance of osteoclastoma as first described by N6laton (1860) is of tumours consisting essentially of spindle cells, round cells, and multinucleated giant cells with an abundance of nuclei. It is a rare tumour, which until recently had not been differentiated from other fibrous tumours of bone, and usually occurs at the ends of long bones, although a few have been reported in the orbit and in the region of the sphenoid and the labyrinth. This paper reports a case of osteoclastoma of the orbit.