Clinical outcomes and risk factors for local failure and visual impairment in patients treated with Ru-106 brachytherapy for uveal melanoma

Abstract

Background and purpose

Small uveal melanomas are preferably treated with eye-sparing therapies such as brachytherapy or proton beam therapy. Knowledge of clinical outcomes and risk factors is important for personalized patient counselling.

Materials and methods

Data of all choroidal melanoma patients treated at the Leiden University Medical Center between 2012–2019 with Ruthenium-106 brachytherapy were collected. Time-to-event analyses were performed with the Kaplan-Meier method, risk factors for local failure and visual acuity (VA) decline were identified using Cox proportional hazards models with predefined covariates.

Results

719 patients were included. Median tumour prominence and diameter were 3.8 mm and 11.6 mm, respectively. 52 % of tumours were centrally located, and 19 % were juxtapapillary. Five-year overall survival, eye retention and local failure rates were 83 %, 95 %, and 8 %, respectively. Juxtapapillary location, lower tumour apex doses, and T3-4 tumour stage were significantly associated with local failure. Patients with juxtapapillary tumours had 20 % risk of local failure. Five years posttreatment, 47 % of patients had no functional visual impairment (Snellen VA ≥ 0.5). Lasting functional visual impairment was associated with baseline vision, central tumours, and scleral dose. Patients with central tumours had 75 % risk of mild or worse visual impairment after 5 years.

Conclusion

Ruthenium-106 brachytherapy yields good local control and visual outcomes in patients with choroidal melanoma. Juxtapapillary tumours have a high risk of local failure and alternative therapies should be considered in these patients, if available. Patients with central tumours, and those with decreased pre-treatment vision should be counselled on the risk of visual impairment.