Overview
Adenoma of the RPE is a rare intraocular neoplasm that can develop from a solitary CHRPE or areas of reactive RPE hyperplasia. They can very rarely (if ever) metastasize.
RPE adenomas appear as a dark brown or black nodule that grows slowly from the RPE to often invade the neurosensory retina. They may develop a retinal feeding artery and draining vein and lead to intraretinal and subretinal exudation. Some forms of RPE adenomas may also be amelanotic.
OCT shows an elevated lesion with an irregular or "rugged" surface with posterior optical shadowing. It may be associated with an exudative retinal detachment, intraretinal and/or subretinal fluid. Remote macular oedema may also be seen.
B-scan ultrasound shows an elevated mass with moderate to high internal reflectivity, although the scarcity of this tumour does mean very few cases have been reported in the literature.
Differential diagnosis
References
Ly, Angelica, Nivison-Smith, Lisa, Hennessy, Michael & Kalloniatis, Michael. (2015). Pigmented Lesions of the Retinal Pigment Epithelium. Optometry and Vision Science, 92, 844-857.
Shields JA, Shields CL. Tumors and Related Lesions of the Pigmented Epithelium (2017) Asia Pac J Ophthalmol (Phila). Mar-Apr;6(2):215-223.