Presenters: Marion Lam France, Valérie Krivosic France

This was a case of an unexpected pigmented lesion of the retina, can you guess what it was?

Case Summary:

A 75-year-old woman was referred for an asymptomatic exudative pigmented mass of the peripheral retina. She had a medical history of breast cancer in remission. The fundus of her left eye showed a pigmented mass with surrounding lipid exudation, and a feeding vessel. The SD-OCT scan of the lesion showed a lesion located in the outer retina with an overlying thin retina. Macular OCT was normal. Fluorescein angiography (FA) showed an early hypofluorescence of the lesion with a feeding artery and then a late hyperfluorescent lesion. Indocyanine green angiography (ICGA) showed a hypofluorescent lesion during all the sequence. Ultrasonography showed a dome-shaped lesion with acoustic solidity.

Based on the clinical and imaging features, the diagnosis of adenoma/adenocarcinoma of the retinal pigment epithelium (RPE) was made. Shields et al. have described a series of 51 cases of RPE adenoma/adenocarcinoma (1). It is a very rare, usually unilateral, acquired, darkly pigmented intraocular tumor of the RPE occurring in patients with a mean age of 51 years at the time of the diagnosis. The clinical presentation varies from an elevated pigmented nodule with surrounding lipid exudation to larger mass lesions with dilated retinal feeding arterial vessels, exudative retinal detachment and vitreous seeding or hemorrhage. The macular features include macular exudation, macular edema, or epiretinal membrane. It is rarely metastatic, and can arise from congenital RPE hypertrophy (in 22% of cases). FA and ICGA features are usually similar to those found in our case.

Ultrasonography frequently shows an abruptly elevated lesion with acoustic solidity (in 82% of cases), that can be dome-shaped in some cases. It may be mistaken for other tumors, in particular choroidal melanoma. In the past, a few cases were misdiagnosed for melanoma and thus enucleated. In case of any doubt, fine needle aspiration biopsy for cytopathologic evaluation may help to support the diagnosis. Observation is usually consensual for small asymptomatic tumors. The treatment plan is more controversial for symptomatic progressive tumors and may include local resection, enucleation or other therapies (e.g., laser, plaque radiotherapy) with variable results. (2) In our case, a 2-year observation did not show any tumor growth.

Williams BK, Di Nicola M, Acaba-Berrocal LA, Milman T, Mashayekhi A, Lucio-Alvarez JA, et al. Adenoma and Adenocarcinoma of the Retinal Pigment Epithelium: A Review of 51 Consecutive Patients. Ophthalmol Retina. août 2020;4(8):829‑39.
Sreenivasan J, Rishi P, Das K, Krishnakumar S, Biswas J. Retinal Pigment Epithelium Adenoma and Adenocarcinoma: A Review. Ocul Oncol Pathol. mars 2021;7(2):121‑32.