Midperipheral Retinal Pigment Epithelial Detachment Masquerading as Choroidal Melanoma Payal Thakkar, Poonam Varsani, Nura Salameh, Malinda Cafiero, Cathy Marques, Mayur Bhavsar VANJ/SUNY

Background

Choroidal melanoma is a serious life-threatening malignancy simulated by a host of pseudomelanomas. This discussion will highlight ways to differentiate between them in order to make the appropriate diagnosis, treatment, and management decisions.

I. Case history

66 year old white male Referred for wellness exam from community based outpatient clinic where teleretinal diabetic screening photo revealed lesion OD

Ocular History: Cataract extraction OU Diabetes without retinopathy OU (-) Age-related macular degeneration

Medical History: (+) Diabetes Mellitus Type II, HbA1C: 7.0 (+) Hypertension (+) Hyperlipidemia

Medications: metformin (850mg BID), lisinopril (20mg QD), hydrochlorothiazide (12.5mg QD), aspirin (81mg QD)

II. Pertinent findings

BCVA: 20/20 OD, OS Anterior Segment: Unremarkable OD, OS

Posterior Segment: Initial VA clinic visit: Midperiphery: OD ~1.0 DD V x 2.0 DD H white, elevated lesion. ~3.5 DD superior- temporal from ONH; Surrounded by pigment; Does not disappear with red-free. OS Unremarkable

Follow-up VA clinic visit: Midperiphery: OD ~2.0 DD V x 2.5 DD H white, elevated lesion, ~3.0 DD superior- temporal from ONH, with associated active hemorrhage OS Unremarkable Ancillary Tests:

Initial VA clinic visit: B-SCAN ULTRASOUND OD: Elevated lesion, appears dense, no hollowness noted FUNDUS PHOTOGRAPHY: ~1.0 DD V x 2.0 DD H white, elevated lesion OPTICAL COHERENCE TOMOGRAPHY (OCT) – STRATUS: OD: All retinal layers elevated in both horizontal and vertical dimensions. Lesion appears choroidal in origin.

Initial private ocular oncologist visit: FUNDOSCOPY: Extensive peripheral hard drusen in both eyes. Lesion of 2x1.8mm in basal dimensions. Creamy colored with rim of light brown pigmentation. No associated subretinal fluid, orange pigment, or overlying drusen. OCT: focal area of RPE detachment with dense material under RPE. INTRAVENOUS FLUORESCEIN ANGIOGRAPHY: Blockage of underlying choroidal hyperfluorescence in all the phases of angiography.

Follow-up VA clinic visit: FUNDUS PHOTOGRAPHY OD: Shows RPE detachment with associated fresh choroidal neovascular membrane (CNVM)

III. Differential diagnosis

Choroidal nevus, choroidal osteoma, choroidal hemangioma, congenital hypertrophy of the retinal pigment epithelium, melanocytoma, central serous chorioretinopathy, choroidal detachment, choroidal hemangioma, lymphoma, choroidal metastasis, pigment epithelial detachment, peripheral exudative hemorrhagic chorioretinopathy

Shields, Carol L., Janet Manalac, Chandana Das, Kyle Ferguson, and Jerry A. Shields. "Choroidal Melanoma: Clinical Features, Classification, and Top 10 Pseudomelanomas."Current Opinion in Ophthalmology 25.3 (2014): 177-85.

IV. Diagnosis/discussion

Retinal pigment epithelial detachments are associated with chorioretinal diseases, most commonly age-related macular degeneration, and occur in the posterior pole near or on the macula; however, some are idiopathic, and in even rarer cases, in the mid- periphery. The different types of retinal pigment epithelial detachments include: serous, fibrovascular, drusenoid, and hemorrhagic. Because retinal pigment epithelial detachments can often masquerade as choroidal melanoma, history and ancillary testing like intravenous fluorescein angiography, B-scan ultrasonography, and OCT are necessary for confirmation.

V. Treatment/management

Treatment of retinal pigment epithelial detachment depends on the severity and location of the detachment. While observation may be appropriate for serous, fibrovascular, and drusenoid RPE detachment without detectable CNVM, hemorrhagic RPE detachments should be treated with anti-vascular endothelial growth factor agents like ranibizumab or bevacizumab, photodynamic therapy, or both.

Zayit-Soudry, Shiri, Iris Moroz, and Anat Loewenstein. "Retinal Pigment Epithelial Detachment." Survey of Ophthalmology 52.3 (2007): 227-243.

VI. Conclusion

Retinal pigment epithelial detachments along with many other retinal and choroidal lesions may masquerade as choroidal melanoma. Ancillary testing along with regular follow up is vital to discern between pseudomelanoma and true melanoma. Early and accurate diagnosis is essential in order to prevent permanent vision loss and systemic complications.