Iris mammillations as the only sign of ocular melanocytosis in a child with choroidal melanoma.

An 8-year-old girl had visual loss in her left eye over 2 months. Ocular examination showed that visual acuity was counting fingers in the left eye. The left iris was moderately pigmented and thickened with numerous confluent, dome-shaped elevations on its surface, consistent with iris mammillations arising from ocular melanocytosis. There was total retinal detachment and an inferiorly located large amelanotic choroidal mass compressing the optic nerve. A specimen from a fine-needle aspiration biopsy showed spindle and epithelioid melanoma cells. The eye was enucleated. Pathologic examination showed that the bland melanocytes comprising the anterior border layer of iris formed focal aggregates, corresponding to the iris mammillations observed clinically. The uvea was diffusely thickened. Arising from the posterior choroid and obscuring the optic nerve head was a moderately pigmented spindle and epithelioid cell choroidal melanoma with diffuse lymphocytic infiltration and high mitotic activity. This case demonstrates that iris mammillations can be the initial manifestation of ocular melanocytosis in the absence of scleral pigmentation.