A 52-year-old woman noted loss of vision in August 1984. Clinical examination disclosed iris cysts and ciliary body cysts, macular edema, and uveal nevi. Cataract extraction and pressure-lowering operations were required in both eyes because of a tumor-induced angle-closure glaucoma. Vision, however, progressively decreased to light perception in each eye. Both eyes were finally enucleated because a malignant melanoma could not be ruled out, though iris tissue obtained in 1985 suggested a nevuslike process. Histologic study indicated a bilateral uveal hyperplasia. Results of light and electron microscopy, immunologic studies, and suspension cell culture suggested that the uveal hyperplasia was more likely a melanoma of low malignancy than a nevuslike process. We could not detect an extraocular primary tumor and assumed that this condition constituted an oncogenic syndrome.