Ruthenium-106-Brachytherapy for the treatment of ocular medulloepithelioma

Introduction: Ocular medulloepithelioma is a rare intraocular neoplasm which is believed to be of congenital origin but is often diagnosed between 2nd and 10th year of life due to symptomatic presentation. It arises mostly from the ciliary body and carries an excellent overall survival prognosis if not extended extraocular. Primary enucleation has been favored as a first line treatment option in most cases but in last decades effort has been made to offer globe saving treatment options to patients and families. Experiences from few cases series highlight brachytherapy as most promising treatment option so far which has mostly been utilizing Ruthenium-106 or Iodine-125. We herewith report further results of the use of Ruthenium-106 brachytherapy as globe-salvage attempt in ocular medulloepithelioma. Methods: Retrospective case series and data analysis of 5 eyes in 5 children treated with Ruthenium-106 brachytherapy from 01/2002 to 10/2024. Results: Mean age at treatment was 5 years (11months to 11 years) with a mean tumor thickness of 5.3mm (2.9-6.7 mm) and a follow-up of 78 months (11-172 months) after treatment. Mean dosage applied for apex and sclera was 82Gy (70-89 Gy) and 772 (317-1033 Gy) respectively. Two eyes had to be enucleated after 3 months and 11 years respectively, whereas histological examination showed no evidence of viable tumor cells. One eye showed recurrence after 34 months which was treated with re-brachytherapy. Most frequent complication was development or worsening of cataract which was successfully operated in 2 eyes. Only two children had a visual acuity of >20/400 (20/50 and 20/80). None of the children showed signs of metastasis, and all children are alive during follow-up period. Conclusion: Ruthenium-106 brachytherapy is an effective treatment modality for ocular medulloepithelioma. Frequency of anterior segment complications were high in our cohort leading to relatively low long-term visual acuity.