Cytopathologic diagnosis of benign lesions simulating choroidal melanomas.

In three cases of benign pigmented lesions (one melanocytoma and two pigment epithelial adenomas) there was evidence of tumor growth and the lesions were referred to us as uveal melanomas. The fine needle aspiration biopsy specimens were correctly interpreted in the operating room as being benign tumors. The pigment granules in these benign pigmented lesions are much larger than are observed in uveal melanomas. When they were visible through the heavy pigmentation, the cellular detail appeared benign. In two cases the tumors were successfully resected with cyclochroidectomy techniques and the visual outcome was good. The third eye was studied after it had been removed at another institution. Fine needle aspiration biopsy can often differentiate a benign-simulating pigmented lesion from uveal melanoma.