Abstract
Purpose :
Anti-vascular endothelial growth factor (anti-VEGF) therapy has been shown to suppress radiation maculopathy (RM). We evaluated the efficacy of prophylactic intravitreal bevacizumab (IVB) to prevent or delay RM in those eyes at highest risk for RM (subfoveal, juxtafoveal, perifoveal and/or when the radiation dose to fovea is greater than or equal to 50 Gray).
Methods :
Retrospective chart-review of patients treated with palladium-103 plaque radiotherapy for choroidal melanoma (CM) from 2014 to 2017. Each was treated with the anti-VEGF bevacizumab prior to the onset of RM. Each eye was at high risk for developing RM based on total radiation dose to the fovea and tumor location. Prophylactic IVB was defined as treatment prior to onset of early RM findings (CWS, RH, ME) and administered within 6 months of plaque radiation therapy. Outcome measures were EDTRS visual acuity (VA), M, CWS, RH and ME measured by macular anatomy measurements on optical coherence tomography (OCT). Clinical features of RM were evaluated by indirect ophthalmoscopy, fundus photography and fluorescein angiography.
Results :
Sixteen eyes were evaluated. American Joint Committee on Cancer Staging T-size ranged from T1 (n=11) to T2 (n=5). The mean foveal dose was 101 Gray, median 98 Gray, and range 38 to 184 Gray. IVB was initiated an average of 23 days, median 14 days, and range of 7-113 days from plaque radiation therapy. Thirteen patients (81%) had initial visual acuity of 20/40 or better and 3 (17%) had between 20/50 to 20/200. Average follow-up was a mean 29 months, median 29 months, and a range of 13 to 47 months. As compared to their VA at diagnosis, 62.5% of patients (n = 10) were noted to have no change or improvement in VA, 25% of patients (n = 4) remained within 2 EDTRS lines and 12.5% (n = 2) lost > 3 lines of vision. One patient developed Stage 3 radiation retinopathy (RR) and four patients developed stage 2 RR at the time of last follow-up. Compared to pre-treatment measurements, OCT-CFT measurements decreased a mean 144.50 microns and macular anatomy remained intact. No complications could be related to IVB therapy.
Conclusions :
The mean onset of palladium-103 plaque related RM without IVB has been reported to be 18 months; prophylactic IVB appears to be a well-tolerated method to preserve vision and prevent or delay RM in high risk choroidal melanoma patients following plaque therapy.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.