DIAGNOSIS OF INTRAOCULAR LYMPHOMA BY FLOW-CYTOMETRY

PURPOSE: To evaluate flow cytometry of vitreous cellular specimens as a means of diagnosing intraocular lymphoma and ocular inflammatory dis ease. METHODS: We undertook a retrospective, observational study of he matopoietic cell-surface markers in 20 patients with vitreous cellular infiltration in whom lymphoma was considered in the differential diag nosis, Immunophenotyping of vitreous cells obtained by vitrectomy was performed by flow cytometry using antibodies directed against specific cell surface antigens, including ones associated with B-lymphocyte an d T-lymphocyte lymphomas and activated inflammatory cells, Smears mere examined cytologically, Cytofluorography was compared with the cytopa thologic diagnosis and with final diagnosis. RESULTS: With flow cytome try, a diagnosis of intraocular lymphoma was confirmed in two of. four patients with known lymphoma, one of whom had;recurrent disease after radiation, and not confirmed in two patients who had had prior treatm ent with radiation or corticosteroids, In six patients with no prior d iagnosis of lymphoma, five mere diagnosed with lymphoma on the basis o f cytofluorography, Thus, seven (70%) of 10 patients with intraocular lymphoma were diagnosed by cytofluorography compared with three (30%) of 10 with lymphoma diagnosed by cytology. With now cytometry, 10 pati ents with uveitis or intraocular infections were distinguishable from patients with lymphoma by lack of a monotypic population and, in some cases, by elevated CD4:CD8 ratios and a high percentage of activated c ells. CONCLUSIONS: Cytofluorography of vitreous cells is an effective alternative or adjunct to cytology, Information can be gained from spe cimens that are uninterpretable by routine cytology, The optimal techn ique for diagnosis may vary among institutions.