Adenoma of Retinal Pigment Epithelium: A case report

Koh, Jae Soo; Chi, Je G

Abstract

A retinal pigment epithelium tumor is extremely rare, and the distinction from malignant melanoma or reactive hyperplasia of pigment epithelium is mandatory, clinically or pathologically. We report a case of adenoma of retinal pigment epithelium. A 21 year-old female presented with a sudden decrease of visual acuity. She had no previous inflammatory ocular disease. Fundic examination revealed an elevated mass at the temporal side of the right eye. With the suspicion of choroidal malignant melanoma, a right eye enucleation was done. Grossly there was a 0.7x0.5 cm dark soft broad-based elevated lesion in the temporal side. The anterior border was the ora serrata, and the posterior border reached the equatorial area. The tumor was confined to the intraocular portion. Histologically, the tumor mass was composed of the cuboidal or columnar cells arranged in papillary, trabecular, or solid pattern with fine fibrovascular stroma. The tumor cells were heavily pigmented. The cytoplasmic border of the tumor cell was indistinct and there was a finely granular brown pigment diffusely scattered in the cytoplasm. Mild anisokaryosis noted, but hyperchromatism or pleomorphism were negligible. The nucleoli were small. A transition between normal retinal pigment epithelium and tumor mass was noted. Reactive gliosis was noted at the periphery of the tumor.