Long-term visual outcomes and side effects of ruthenium plaque brachytherapy in 310 eyes with small choroidal melanoma.

Abstract

Background/aims: To report the long-term visual outcomes and side effects in patients with small choroidal melanoma (CM) undergoing ruthenium-106 (Ru-106) plaque brachytherapy.

Methods: Retrospective, interventional, consecutive series of small CM ≤2.5 mm in height and ≤16 mm in largest basal diameter treated with Ru-106 plaque with a median radiation dose of 100 Gy prescribed to tumour apical height.

Results: 310 patients (160 men) with a mean (SD) age of 58.4±14.1 years met the study inclusion criteria. The median follow-up was 57.5 (range 3.4-170.5) months. The mean tumour baseline thickness was 1.9±0.4 (range 0.4-2.5) mm. The mean baseline logarithm of the minimum angle of resolution (logMAR) of best corrected visual acuity (BCVA) was 0.21±0.4 (Snellen equivalent 6/9; range -0.1 to 1.5). Mean final BCVA was ≤0.3 logMAR (Snellen equivalent 6/12) in 161 patients (54.2%), better than 1.0 logMAR (Snellen equivalent 6/60) and <0.3 logMAR in 59 patients (19.9%), and ≥1.0 logMAR in 77 patients (25.9%). Kaplan-Meier estimates of poor final VA (≥1.0 logMAR) were 13.2% at 5 years and 54.5% at 10 years. Early and late complications developed in 20.6% and 42.6% of cases, respectively. Radiation maculopathy was the most frequent late side effect (29% of patients) with Kaplan-Meier rates of 18.2%, 31.7% and 42.1% at 3, 5 and 10 years, respectively. Older age, lipofuscin, proximity to fovea, final tumour elevation and radiation maculopathy predicted visual loss ≥5 Snellen lines.

Conclusion: Despite early and late complications in 20.6% and 42.6% of cases, Ru-106 brachytherapy for small CM allows retention of BCVA ≤0.3 logMAR in half of the eyes.