Disciform lesion overlying melanocytoma simulating progression of choroidal melanoma.

A 49-year-old white patient presented with a small pigmented lesion nasal to the disc. The clinical appearance of the area in question was noted to change over a four year period and simulated a progressively enlarging choroidal melanoma. On enucleation, the lesion was histopathologically proved to be a melanocytoma located nasal to the optic nerve head. It caused--or was at least associated with--an overlying disciform hemorrhagic and transudative response secondary to a neovascular ingrowth through Bruch's membrane. Thus, a melanocytoma must now be considered another of the possible causes of a disciform-shaped fundus lesion.