Reticulohistiocytoma of the limbus and cornea. A clinicopathologic study of two cases.

Reticulohistiocytoma is a rare, benign histiocytic lesion usually occurring as an isolated skin nodule or as part of a systemic disorder known as "multicentric reticulohistiocytosis." The clinical and histopathologic findings of two women who presented with a single, painless mass localized to the cornea and limbus without skin lesions or systemic disease are reported. Histopathologically, the lesions were composed predominantly of large mononuclear and a few multinucleated cells with finely granular, "ground-glass" cytoplasm and large nuclei with prominent nucleoli. Immunohistochemical and electron microscopic studies conformed the histiocytic nature of these cells. Reticulohistiocytoma should be included in the differential diagnosis of epibulbar benign histiocytic lesions.