Abstract
Purpose: :
To describe the clinical, histopathologic, immunohistochemical, and ultrastructural features of a cases series of low grade conjunctival spindle cell tumors.
Methods: :
Four cases of low grade spindle cell tumors of the conjunctiva were identified in the database of the L.F. Montgomery Ophthalmic Pathology Laboratory, Emory University. Clinical information, including patients’ age, sex, clinical appearance, pre-operative diagnosis, and post-operative course was obtained. Formalin-fixed paraffin-embedded specimens from these cases were routinely processed and stained with H&E and PAS. Immunohistochemical stains, including vimentin, S100, CD34, SMA, and CD68, were performed. Two cases were further analyzed by electron microscopic examination.
Results: :
The tumors occurred in patients aged between 41 to 53 years and did not recur after excisional biopsy. Histopathologically, all tumors exhibited spindle-shaped cells in a partly myxoid, partly collagenous stroma that contained vascular-like spaces. Some of the tumor cells contained pseudonuclear inclusions; multinuclear cells were also present. Mitotic figures were not observed. Immunohistochemical stains were positive for CD34, vimentin, and focally CD68, but negative for S100 and SMA staining. The differential diagnoses included neurothekeoma, subconjunctival herniated orbital fat, fat-free spindle cell lipoma, fat-free pleomorphic adenoma, myxoma, pseudotumor, neurofibroma, fibrous histiocytoma, and hemangiopericytoma.
Conclusions: :
The conjunctival mesenchymal proliferations in our series lacked features in each of the entities in the differential diagnoses. We propose to term this entity "low grade spindle cell mesenchymal tumor of conjunctiva" indicating the mesenchymal derivation as well as the benign nature of this entity. We recommend excisional biopsy of this tumor with ophthalmologic follow-up examination.
Keywords: pathology: human • oncology • conjunctiva