Incidence, Risk Factors and Outcomes of Cataract Surgery after Plaque Brachytherapy for Posterior Uveal Melanoma

Purpose: To examine incidence, risk factors, and outcomes of cataract surgery after plaque brachytherapy for posterior uveal melanoma. Design: Retrospective interventional cohort study contrasted with general population data. Methods: All patients treated with plaque brachytherapy for a posterior uveal melanoma at Sweden's national referral center between 2010 and 2022 were included (n = 933). These patients were cross-referenced with data from the Swedish National Cataract Register. Competing risk incidences and outcomes of cataract surgery were compared with a random sample of 1000 individuals from the general population. Results: The 12-year incidence of cataract surgery after plaque brachytherapy was 27 % (95 % CI 23–31 %), which markedly exceeded the incidence of 16 % in the general population (95 % CI 13–18 %, Gray's P < 0.001). Patients treated with Iodine-125 had significantly higher incidence than patients treated with Ruthenium-106, and the latter had greater incidence than the general population (P < 0.001). In univariate competing risk regressions, older patients, female sex, thick tumors, and Iodine-125 were associated with cataract surgery. In multivariate analysis, older patients and Iodine-125 retained their significance. Outcomes of cataract surgery were overall similar in the plaque brachytherapy and general population, but the general population more often received post op. topical NSAID. Conclusions: In this study, plaque brachytherapy for posterior uveal melanoma was associated with a significantly increased incidence of cataract surgery. Treatment with the gamma emitting isotope iodine-125 and older patient age at the time of brachytherapy emerged as the major risk factors. Outcomes of cataract surgery were comparable to the general population.