# Analysis of the Influence of Demographic, Clinical and Physical Factors on the Occurrence of Ocular Complications After Ruthenium-106 and Iodine-125 Brachytherapy as Well as Proton Therapy of Uveal Melanoma

## TL;DR

This study analyzed 300 patients to identify factors influencing eye complications after different radiation treatments for uveal melanoma.

## Contribution

The study identifies specific factors like tumor location and treatment type that significantly affect ocular complications after uveal melanoma therapy.

## Key findings

- Cataract was most common (84.36%) and associated with older age.
- I-125 brachytherapy was frequently linked to maculopathy, retinopathy, and optic neuropathy.
- Tumor location involving the macula or optic disc was a major risk factor for multiple complications.

## Abstract

The objective of this study, which is a retrospective analysis of 300 patients’ medical records, was to assess the influence of various factors related to the characteristics of patients, tumors and treatment applied on the occurrence of ocular complications after radiotherapy for uveal melanoma. Most often, these complications lead to a significant deterioration of visual acuity in the treated eye. All patients were treated at the Department of Ophthalmology and Ocular Oncology, University Hospital in Krakow, Poland. The most common complications of treatment were found to be: cataract (84.36%), maculopathy (52.67%) and retinopathy (46.67%). The factors that were found to be most frequently associated with the occurrence of complications in the multivariable analysis were: tumor location involving the macula and/or optic disc, the use of iodine-125 brachytherapy, younger age and greater tumor thickness. We believe that the study results may contribute to the improvement in existing, and the invention of new, therapeutic methods.

Background: The aim of this study was to evaluate the influence of demographic, clinical and physical factors on the occurrence of ocular complications after ruthenium-106 (Ru-106) brachytherapy, iodine-125 (I-125) brachytherapy and proton therapy of uveal melanoma. Methods: A retrospective analysis of 300 patients’ electronic and paper medical records treated for uveal melanoma at the Department of Ophthalmology and Ocular Oncology, University Hospital in Krakow, Poland, from May 2014 to December 2016 was performed. The created database, which includes numerous parameters characterizing patients, tumors, applied treatments and their effects, with particular emphasis on the occurrence of ocular complications, was subjected to detailed analysis. The influence of selected factors on the occurrence of identified complications was checked by performing a univariable Cox proportional hazards regression analysis, and then the factors that were statistically significant were included in a multivariable Cox proportional hazards regression analysis which gave the final results. Results: Of the 300 patients, 125 (41.67%) were treated with Ru-106 brachytherapy (87 (29%) with CCB plaque and 38 (12.67%) with COB plaque), 102 (34%) with I-125 brachytherapy and 73 (24.33%) with proton therapy. Mean follow-up was 88.63 months (median 89, range: 20–127). The occurrence of cataract was associated with the older age of patients. Maculopathy was associated with female sex, younger age, use of I-125 brachytherapy, tumor location involving the macula and/or optic disc and moderate tumor pigmentation. Diagnosis of systemic hypertension was associated with a lower risk of maculopathy. Retinopathy was associated with younger age, tumor location involving the macula and/or optic disc and the use of I-125 brachytherapy. Optic neuropathy was associated with younger age, greater tumor largest base diameter, tumor location involving the macula and/or optic disc and the use of I-125 brachytherapy. Secondary glaucoma was associated with baseline best corrected visual acuity (BCVA) weaker than 0.5, greater tumor thickness, involvement of the left eye and the use of I-125 brachytherapy. Vitreous hemorrhage was associated with greater tumor thickness, tumor location including the macula and/or optic disc and mushroom-shaped tumor. Conclusions: Our study demonstrated an association between demographic, clinical, and physical factors and the occurrence of ocular complications after radiotherapy for uveal melanoma.