Abstract
Purpose :
To evaluate the incidence of radiation retinopathy, its predictive risk factors and to reveal differences or superiorities in between different treatment options for macular edema after proton beam therapy for uveal melanoma.
Methods :
All patients treated with primary proton beam therapy for choroidal and ciliary body melanoma at the oncology service between May 1998 and June 2014 with a minimum follow-up of 12 months were included. Excluded were all patients who underwent re-irradiation, or vitrectomy due to exudative retinal detachment or for tumor-resection. For evaluation of treatment options all patients presenting with radiation maculopathy treated only with intravitreal treatment (antiangiogenic or corticosteroids) since January 2011 were included.
Results :
1127 patients matched the inclusion criteria. From this group of patients 68.1% developed radiation retinopathy after 18.9 months (2.0-99.84 months). Mean follow-up was 53.4 months (12-170.4 months). Independent risk factors for radiation retinopathy were tumor height, largest basal diameter, and central location. In total 78 patients received intravitreal treatment due to radiation maculopathy of whom 38 patients received bevacizumab- injections, 35 patients triamcinolone acetonide injections, and 5 patients a dexamethasone implant. In the bevacizumab group visual acuity (VA) improved in 11 patients (28.9%) by on average 0.25 logMAR (0.1-0.4 logMAR) and remained stable in 24 patients (63.2%) 4 weeks after injection. In the triamcinolone group VA showed improved outcomes in 10 patients (28.6%) by 0.25 logMAR (0.1-0.4 logMAR) and stability in function in 20 patients (57.1%). Four weeks after dexamethasone implantation VA remained stable in 4 patients (80%). Foveal thickness significantly decreased in every group without any differences regarding functional outcome or reduction in foveal thickness.
Conclusions :
The risk for developing radiation retinopathy is higher in centrally located uveal melanoma regardless of doses of the sensitive structures. Furthermore this study showed that antiangiogenic or corticosteroid intravitreal treatment led to reduced foveal thickness and visual improvement in some patients without showing differences or superiorities. Long-term VA remained limited in 3/4 of patients. Better functional outcome would be expected if treatment was applied directly after macular edema was present and was continued requiring more intravitreal injections.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.