Cytologic evaluation of lymphoproliferative lesions of the orbit/ocular adnexa: an analysis of 46 cases.

The cytologic features of 46 lymphoproliferative ophthalmic lesions were evaluated using the "squash" technique and/or touch imprints at the time of frozen section. Of the 46 lesions, 33 were located in the orbit, 12 in the conjunctiva, and one in the eyelid. Fifteen cases were benign (reactive) hyperplasias, and 31 were diagnosed as malignant lymphoproliferative tumors. The cytologic features of the reactive group included a polymorphic lymphoid population intermixed with scattered tingible body macrophages. Within the malignant category, there were 28 malignant lymphomas. All 28 cases were diagnosed as non-Hodgkin's lymphomas. Cytologically, the malignant group consisted of a monomorphic population of atypical lymphoid cells. Of the 31 malignant lymphoid lesions, 58% (18 tumors) were small lymphocytic proliferations. The remaining 13 tumors were classified as follows: mixes small/large cell or pure large cell lymphomas (nine), plasmacytoma (three), and Burkitt's lymphoma (one). Final classification using the Working Formulation was made after evaluating the cytologic preparations and surgical material. In selected cases, the monoclonal nature of the malignant lymphoproliferative lesions was confirmed by flow cytometry and/or immunocytochemistry. Cytologic preparations of the fresh specimens preserve the morphologic details of the tumor cells, which is especially important when evaluating lymphoid lesions. Additionally, multiple smears can be prepared simultaneously for ancillary studies such as immunocytochemistry. Of our 46 lymphoproliferative lesions, two-thirds were diagnosed as malignant lymphomas. Based on the morphologic and immunophenotypic findings, all the malignant lymphomas were B-cell tumors, 50% of which were low grade using the Working Formulation.