Ocular complications after iodine brachytherapy for large uveal melanomas.

PURPOSE: To evaluate anterior and posterior segment complications and their management after iodine 125 plaque brachytherapy (IBT) for large uveal melanoma.
DESIGN: Retrospective nonrandomized interventional study. PARTICIPANTS: Ninety-six patients with a large uveal melanoma according to the Collaborative Ocular Melanoma Study criteria.
METHODS: The patients underwent primary IBT (median dose to tumor apex, 87 Gy). The median tumor height and diameter were 10.7 mm (range, 4.5-16.8) and 16.5 mm (range, 7.3-25.0), respectively, and the median follow-up time was 3.5 years (range, 0.3-10.4). Cumulative incidence analysis and competing risks regression were used to analyze the time to individual complications and to identify risk factors. Death and secondary enucleation were analyzed as competing risks. MAIN OUTCOME MEASURES: Cataract, iris neovascularization, glaucoma, maculopathy, optic neuropathy, vitreous hemorrhage, and persistent exudative retinal detachment (RD).
RESULTS: The 5-year cumulative incidences of cataract, iris neovascularization, and glaucoma were 69% (95% confidence interval [CI], 57%-78%), 62% (95% CI, 50%-71%), and 60% (95% CI, 48%-70%), respectively. Posterior segment complications were less common. The 5-year incidences of maculopathy and optic neuropathy were 52% (95% CI, 35%-65%) and 46% (95% CI, 30%-61%), and those of vitreous hemorrhage and persistent RD were 36% (95% CI, 23%-48%) and 25% (95% CI, 15%-36%), respectively. More than 80% of complications were diagnosed within 3 years. Cataract was the earliest complication to appear. Except for cataract, the cumulative incidence of dying without developing a particular complication was 0.24 to 0.62 times that of first developing the complication. Increasing tumor height, which correlates to increasing doses to adjacent tissues, was associated with time to cataract (P = 0.017), iris neovascularization (P = 0.087), and RD (P = 0.046). Maculopathy and optic neuropathy were associated primarily with distance to the fovea (P = 0.015) and optic disc (P = 0.015), respectively. Of 57 patients with cataract, 47% underwent cataract extraction, and 12% of 51 patients with glaucoma were treated with cyclophotocoagulation. The prevalences of cataract, elevated intraocular pressure, and RD were 43%, 39%, and 13%, respectively, at 5 years.
CONCLUSIONS: The frequency with which ocular complications develop after IBT is notably influenced by competing risks. Cumulative incidence and prevalence analysis provide realistic estimates for patient counseling.