Pseudoretinitis pigmentosa secondary to preretinal malignant melanoma cells.

A 75-year-old white woman with a previously diagnosed malignant melanoma of the choroid presented with pseudoretinitis pigmentosa secondary to epiretinal pigmented cells. Histopathologic examination of the enucleated globe revealed that the retinal pigmentation was due to a preretinal membrane of spindle A malignant melanoma cells, which had been dispersed by the tumor. Scanning electron microscopy of the preretinal tumor cells revealed characteristics similar to those previously reported in tissue culture. The pigment dispersion was associated with retinal perforation by the melanoma, denoting an aggressive, growing tumor that should be treated rather than observed.