Benign Solitary Fibrous Histiocytoma of Xanthomatous Subtype of the Perilimbal Conjunctiva and Adjacent Sclera in a Youth

Aims: To report the clinical and pathological features of a benign fibrous histiocytoma of the xanthomatous subtype in the perilimbal conjunctiva and adjacent sclera in a youth. Methods: An 11-year-old Caucasian boy presented with a yellowish dome-shaped conjunctival mass abutting the inferotemporal limbus of the left eye. The tumor measured 4 mm in its maximum diameter. The lesion was excised and was noted to extend into the sclera. Three years postoperatively, there was no evidence of recurrence. Results: Histopathological examination disclosed a highly cellular lesion composed predominantly of benign-appearing foamy histiocytes without multinucleated giant cells. The tumor contained sparse fibrous septa without a storiform configuration. Immunohistochemical analysis showed diffuse cytoplasmic positive staining with adipophilin, CD34, and CD163. Conclusion: A lesion comprised of numerous homogeneous foamy histiocytes without multinucleated giant cells in the perilimbal conjunctiva and adjacent sclera of a youth is presented as a unique case of a rare variant of fibrous histiocytoma of the xanthomatous subtype.