Ruthenium-106 ocular surface brachytherapy for incompletely excised conjunctival melanoma and squamous cell carcinoma

To examine the efficacy and safety of ruthenium-106 (¹⁰⁶Ru) ocular surface brachytherapy for incompletely excised conjunctival melanoma (CM) and conjunctival squamous cell carcinoma (CSCC) patients, with no adjunctive treatments applied to the primary tumor beds treated with ¹⁰⁶Ru brachytherapy.

A retrospective analysis of a consecutive cohort of eight patients (four with CM and four with CSCC), treated at the Department of Ophthalmology of the University Hospital of Heraklion, was performed. All patients underwent adjuvant ¹⁰⁶Ru plaque brachytherapy using a CCB (BEBIG) plaque, delivering 100 Gy at a depth of 1 mm.

An overall local tumor control rate of 75% was observed during a follow-up period of 18-75 months. In two patients (one CM and one CSCC), orbital exenteration was required due to orbital invasion. Both cases involved neglected and extensive lesions, suggesting possible pre-existing microscopic deeper infiltration. No radiation-related ocular surface toxicity was observed.

In line with previous reports, these findings highlight the role of ocular surface brachytherapy in the management of incompletely excised conjunctival malignancies. Ruthenium-106 surface brachytherapy may represent an effective sole adjunctive treatment option for selected cases of CM and CSCC, even when using plaques designed for intra-ocular applications, such as CCB (BEBIG) plaque.