Iodine Plaque Brachytherapy a Customized Conservative Approach to the Management of Medium/Large-sized Uveal Melanoma

The objective of this study was to assess the role of iodine (¹²⁵I) plaque brachytherapy in the management of uveal melanoma.

This is a retrospective study of 50 patients (median age 67 years; range=33-86 years) with uveal melanoma, treated with ¹²⁵I plaque brachytherapy at the University Hospital of Pisa. Uveal melanoma was diagnosed with A-scan and B-scan standardized echography, fluorescein angiography, indocyanine green-angiography, optical coherence tomography, and/or magnetic resonance imaging. The primary outcomes assessed were local control, overall survival, disease progression, globe preservation, and metastases. Secondary outcomes were acute and late radiation adverse effects.

Inclusion criteria comprised Eastern Cooperative Oncology Group performance status ≤2, life expectancy >6 months, and tumor thickness ≤10 mm and\or diameter ≤20 mm. All the patients were treated with ¹²⁵I plaque brachytherapy, with a prescription dose of 85 Gy to the tumor apex. The 5-year rate of local control, progression-free survival, metastasis-free survival, enucleation-free survival, and overall survival were 83.0%, 81.4%, 90.3%, 83.1%, and 92.1% respectively. Twenty-four patients (48.0%) had one or more acute and late toxicities. The most common acute adverse events (CTCAE vs. 5.0) grade 1-3 were conjunctivitis and eye pain (6.0%). Regarding late events, radiation retinopathy grade 1-3 occurred in 18.0% of cases, while grade 1-3 vitreous hemorrhage in 2.5%.

¹²⁵I plaque brachytherapy offers an effective and safe approach for selected cases of uveal melanoma, due to the reported satisfactory results in terms of local control, eye conservation and survival.