Proliferative Radiation Retinopathy after Plaque Radiotherapy for Uveal Melanoma

Purpose: To determine risk factors, occurrence rate, management, and outcome of proliferative radiation retinopathy (PRR) after plaque radiotherapy for uveal melanoma. Design: Case-control study. Participants: Three thousand eight hundred forty-one patients who underwent plaque radiotherapy for uveal melanoma were entered into the study. Methods: Retrospective review of medical records. Main Outcome Measures: Proliferative radiation retinopathy after plaque radiotherapy for uveal melanoma. Results: Of 3841 eyes treated with plaque radiotherapy for uveal melanoma, PRR developed in 5.8% at 5 years and in 7% at 10 and 15 years using Kaplan-Meier analysis. The mean time to onset of PRR was 32 months ( median, 30 months; range, 4-88 months). On univariate analysis, baseline factors predictive of PRR (P<0.05) included young age, diabetes, hypertension, Hispanic race, shorter tumor distance to the optic disc and to the foveola, Bruch's membrane rupture, choroidal location of the tumor, subretinal fluid, higher radiation dose to the optic nerve and to the foveola, higher radiation rate to the tumor apex and to the tumor base, additional transpupillary thermotherapy, and notched plaque. In the multivariate model, young age ( odds ratio [ OR], 1.44; 95% confidence interval [CI], 1.25-1.67, per decade decrease), diabetes mellitus ( OR, 2.73; 95% CI, 1.69-4.40), and shorter tumor distance to the optic disc ( OR, 1.10; 95% CI, 1.04-1.17) were related to the occurrence of PRR. The most common forms of management included panretinal photocoagulation (70%), vitrectomy (21%), and observation (17%). Resolution of the neovascularization was obtained in 63% of eyes after treatment. Conclusions: Proliferative radiation retinopathy developed in 7% of eyes by 10 years after plaque radiotherapy for uveal melanoma. The main factors for development of PRR included young age, preexistent diabetes mellitus, and shorter tumor distance to the optic disc.