ESTRO 2021 Abstract Book

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ESTRO 2021

acuity over time is presented in table 1. Pre-treatment retinal detachment (HR 2.355, 95%CI 1.297-4.276, p=0.005), tumor volume (HR 1.001 per mm3, 95%CI 1.000-1.001, p=0.001), localization (mid-peripheral HR 2.337, 95%CI 0.993-5.502, p=0.052 and central HR 2.593, 95%CI 1.051-6.398, p=0.039), retina D90 (HR 1.033 per %, 95%CI 1.011-1.055, p=0.004) and macula D90 (HR 1.009 per %, 95%CI 1.003-1.014, p=0.002) were significantly associated with visual loss <0.20. Optic disc D90 (HR 1.003 per %, 95%CI 0.998-1.007, p=0.30), optic nerve D90 (HR 1.048 per mm length, 95%CI 0.937-1.172, p=0.41) and lens D90 (HR 1.004 per %, 95%CI 0.993-1.014, p=0.48) were not associated with an increased risk. The relation between visual acuity, tumor localization and dose parameters is presented in figure 1.

Table 1. Visual outcomes after proton therapy for uveal melanoma

Figure 1. Relation between visual acuity and dose parameters by tumor localisation

Conclusion Proton therapy for large and/or juxtapapillary uveal melanomas yielded good local control, but around 30% of