[A case of benign epithelioma of the ciliary body].

A 34-year-old woman showed a partially pigmented, greyish-white mass at a position of 1 o'clock behind the iris of her left eye. The lens equator was compressed and focal opacity had developed. The adjacent ciliary processes and zonules were intact. Photocoagulation was not effective and dense cataract gradually developed, so we performed extracapsular cataract extraction and partial iridocyclectomy. The tumor was nonencapsulated, nodular and myxomatous in appearance, arising from the pars plicata. Histological examinations revealed that the tumor was composed of nonpigmented cells and a small number of pigmented cell clusters. The cells were arranged like cords or gland-like structure with intervening myxomatous, fibrillar, and partially hyalinous interstitium. There was no finding of malignancy. The tumor showed similar microscopic structure and findings of mucous stains of normal ciliary nonpigmented epithelium and internal basement membrane, so a diagnosis of benign epithelioma was made.