31 Uveal Melanoma

Uveal Melanoma

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THE GEC ESTROHANDBOOKOF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 15/04/2020

the broad experience with 106 Ru eye plaque brachytherapy, largely used in Europe. In a recent study, the local tumour control is 89.6% at 3 years, 83.3% at 5 years, and 80% at 10 years post- treatment, confirming that ruthenium brachytherapy represents a good treatment option for small andmedium-sizedmelanomas. Local recurrence rate is 13.5% at 5 years post treatment similar to that reported by other authors: 11,2 for Ru106+TTT (TTT: Transpupillary ThermoTherapy) and 5.2% for Ru106, 17.3% and 21.2%. Three-year survival is 91.6%, 5-year cancer-free survival reaches 84.6%. Ru‐106 plaque radiation therapy is also effective in the management of iris and anterior ciliary body melanomas, with low recurrence rates (3% at 5 years) and absence of severe Although some European experiences using the Ruthenium-106 plaque had already highlighted the possibility of using an alternative conservative treatment to enucleation, robust evidence came only later. In 1986 the Collaborative Ocular Melanoma Study (COMS) initiated a large randomized multicenter clinical trial comparing enucleation and iodine plaque brachytherapy and demonstrated equivalent survival while offering the potential for visual preservation. Consequently, iodine-125 plaque brachytherapy is now widely accepted as a preferred alternative to enucleation in the treatment of medium-size choroidal melanoma, with the 5-year risk of local treatment failure of 10.3%. The 5-year estimated rates for tumour control, globe salvage, and metastatic-free survival are 98.3%, 96.4%, and 88.2%, respectively. By 12 years, cumulative all-cause mortality was 43% among patients in the125I brachytherapy arm and 41% among those in the enucleation arm. (Table 7) ophthalmic complications. (Table 6) Iodine-125 eye plaque brachytherapy Complications after eye plaque are caused by radiotherapy- specific factors (e.g., total dose, dose rate, and dose volume) and tumour- related factors (e.g., tumour size, location, and its biologically variable response to irradiation). Late anterior segment complications are very rare when ruthenium brachytherapy is used and more often seen with iodine-125. They include dry eye, iris neovascularization, secondary glaucoma, and cataract. Acute intraocular radiation complications include secondary retinal detachment and hemorrhage (vitreous, retinal, or choroidal). The most common late posterior segment complications are radiation retinopathy (RR) and optic neuropathy. ABS2003 . Radiation retinopathy remains a major source of visual morbidity following radiotherapy for malignancies, and the resulting impact on visual acuity depends on the localization of the tumour. A retrospective study reported an incidence of RR with associated retinal neovascularization (proliferative RR) of 5.8% at five years and 7% at ten and 15 years in 3 841 eyes treated with plaque radiotherapy for uveal melanoma. The development of RR has always been related to the total dose of radiation administered to the retina; 35Gy is accepted as the upper safe limit for total dose, although cases of radiation retinopathy have been reported after much lower levels of irradiation. It is characterized by a slowly progressive occlusive vasculopathy, caused by loss of pericytes 13. ADVERSE SIDE EFFECTS

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Fig. 20: Acrylic plaque insert loaded with 125Iseeds (a) followed pretreatment plan (b) - Iodine-125 applicator with acrylic plaque insert for 125Iseeds (c and d)

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Fig. 21: Fundus oculi: Diagnosis (tumour - a) – Follow-up (scar - b)

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Fig. 22: US: Diagnosis (tumour - a) – Follow-up (scar - b)

extension. Since patients with local treatment failure may have an increased risk of developing metastasis and decreased survival, they must undergo treatment for their tumour recurrence. There is no established management for cases of local treatment failure and the therapeutic approach depends on the extent and location of the recurrence and remains a case-by-case decision. Although enucleation has been the most used procedure for recurrent melanoma, recent studies have shown especially in presence of a marginal or elsewhere recurrence, retreatment with plaque brachytherapy may offer a high probability of tumour control. The minimal time gap between the first and the second treatment is not clear. However an interval of at least 6 months should be considered, in cases receiving a high initial dose. (Fig. 21, 22) Ruthenium-106 eye plaque brachytherapy There is a considerable amount of data available today, reflecting