Choroidal Melanoma Treated With Ruthenium‐106 Eye Plaque Brachytherapy: Results of an Australian Statewide Service From November 2020 to January 2025

INTRODUCTION: Uveal melanoma is a rare but aggressive malignancy, predominantly affecting the choroid. This study is the first retrospective review performed on adult choroidal melanoma patients treated with Ruthenium-106 plaque brachytherapy in Queensland. METHOD: The study period was November 2020 to January 2025, where patient, tumour, and treatment factors, as well as local control, salvage treatments, radiation retinopathy, and visual acuity were assessed at 6, 12, 24, and 36 months post-treatment. RESULTS: A total of 151 patients with a mean tumour thickness of 3.85 mm and mean largest basal diameter of 10.2 mm received treatment. A dose of 100 Gy to the tumour apex was prescribed to 88.7% of patients. The short-term risk factor for disease progression was tumour thickness (odds ratio [OR] 2.01, 95% confidence interval [CI], 1.11-3.87; p = 0.025), whereas tumour to optic nerve distance was a protective factor in both the short- (OR 0.55, 95% CI 0.31-0.82; p = 0.013) and long-term (OR 0.75, 95% CI 0.60-0.90; p = 0.005). At 36 months post-treatment, local control was 89.5%, the enucleation rate was 3.3%, tumour thickness (OR 1.77, 95% CI 1.1-2.98; p = 0.022) and sclera dose (OR 1.01, 95% CI 1-1.01; p = 0.045) were risk factors for severe radiation retinopathy. Median visual acuity decreased by one Snellen chart line. When tumour distance to optic nerve or foveola is greater than 3 mm, there was minimal change to visual acuity. CONCLUSION: The findings demonstrate that high-quality plaque brachytherapy can be delivered effectively at a statewide level.