This 81YO male presented with a 9.5mm-thick uveal malignant melanoma with fan-like opacities emanating from the apex of the tumor in his left eye. We suspected early vitreous hemorrhage, pigment shedding, or vitreous seeding.
Early phase angiogram beautifully reveals its internal vascularity, with late leakage from the entire tumor. Vision was 20/70.
The patient underwent diagnostic vitrectomy with plaque radiotherapy. Cytology from the vitreous sample confirmed PRAME, SOX10, and Ki67-positive cells. Genetic expression profiling showed that the tumor was Class 1B, PRAME positive.
Learning Points:
About 20% of patients with a Class 1B lesion will experience clinical metastasis within 5 years. PReferentially expressed Antigen in MElanoma (PRAME) is a gene that can become aberrantly expressed in some malignancies. Its positivity can indicate an increased risk for metastatic disease in Class 1 tumors, but its negativity does not tend to alter prognosis.
Vitreous seeding from a choroidal melanoma before surgical intervention is exceedingly rare. Various approaches have been taken, including immediate enucleation (Cheng et al, Taiwan Journal of Ophthalmology 2017;7:168-171), close observation for recurrence or further seeding (Metz et al, Br J Ophthalmol 2016;100:660-664), or delivery of intravitreal melphalan (Masoomian et al, Retin Cases Brief Rep 2021;15:97-100).
