Radiobiological doses, tumor, and treatment features influence on outcomes after epiescleral brachytherapy. A 20-year retrospective analysis of single-institution: part II

Abstract

PurposeTo assess the influence of the radiobiological doses, tumor, and treatment features on retinopathy, cataracts, retinal detachment, optic neuropathy, vitreous hemorrhage, and neovascular glaucoma at the authors’ institution after brachytherapy for posterior uveal melanoma.Material and methodsMedical records of 243 eyes with uveal melanoma, treated by iodine brachytherapy between 1996 and 2016 at a single center were analyzed. Clinical and radiotherapy data were extracted from a dedicated database. Biologically effective dose (BED) was included in survival analysis performed using Kaplan-Meier and Cox regressions. Relative survival rates were estimated, and univariate/multivariate regression models were constructed for predictive factors of each item. Hazard ratio and confidence interval at 95% were determined. Variables statistically significant were analyzed and compared by log-rank tests.ResultsThe median follow-up was 73.9 months (range, 3-202 months). Cumulative probabilities of survival by Kaplan-Meier analysis at 3 and 5 years, respectively, were: 59% and 48% for retinopathy; 71% and 55% for cataracts; 63% and 57% for retinal detachment; 88% and 79% for optic neuropathy; 87% and 83% for vitreous hemorrhage; 92% and 89% for neovascular glaucoma, respectively. Using multivariate analysis, statistically significant risk factors were: age, tumor apical height, dose to foveola, and location of anterior border for retinopathy; age, dose to lens, type of plaque, and tumor shape, for cataracts; age, tumor apical height, and size of the plaque for retinal detachment; age, plaque shape, longest basal dimension, and BED to optic nerve for optic neuropathy; age, tumor apical height, and tumor shape for vitreous hemorrhage; tumor apical height and BED to foveola for neovascular glaucoma.ConclusionsTumor factors in addition to radiation treatment may contribute to secondary effects. Enhanced clinical optimization should evaluate radiobiological doses delivered to the tumor volume and surrounding normal ocular structures.

Treatment planning considerations for 125I eye plaque brachytherapy

“…It is worth to mention that the techniques were used previously at our institution, and there was no difference in either both local tumor control [4] or complications [3,5]. Moreover, for many side effects, the results were better for patients treated at our institution [3,4,5].…”

“…The workflow in choroidal melanoma interventional radiotherapy is typically articulated in five main issues: 1) Multidisciplinary tumor board: case presentation and treatment choice; 2) Treatment planning: plan calculation and preplan approval; 3) Source preparation: applicator loading and sterilization; 4) Surgery: plaque implantation, treatment; 5) Plaque removal [2,3,4,5].…”

Regression of posterior uveal melanoma following iodine-125 plaque radiotherapy based on pre-treatment tumor apical height

“…Brachytherapy has been proven to be very effective and safe way of treatment, providing a good alternative to surgical removal of the eye. In previous studies with a smaller sample of patients, we have reported results in terms of visual acuity outcome [ 28 ], local failure, globe preservation, mortality, local control [ 29 ], and toxicity [ 30 ]. However, there is no gold standard for tumor basal diameter measurement, and these data may be imprecise and impractical in some cases [ 12 ].…”

Personalized re-treatment strategy for uveal melanoma local recurrences after interventional radiotherapy (brachytherapy): single institution experience and systematic literature review

“…Important tumor and treatment features [ 16 , 17 ] as well as the total dose of treatment may influence the outcomes (as reported in literature) of both Iodine-125 [ 18 ] and Ruthenium-106 [ 19 , 20 ]. That is why there is an increasing evidence in literature towards supporting a personalized approach for shaping target-specific dose distributions [ 21 ].…”