Long-Term Outcomes After Proton Beam Radiation Therapy for Intraocular Vascular Tumors

Abstract

Purpose/Objective(s): To present long-term follow-up for patients with intraocular vascular tumors treated with proton beam radiation therapy (PBRT). Materials/Methods: We performed a review of our prospectively maintained database for all patients with intraocular vascular tumors treated with PBRT at our institution between 1994 and 2012. We report patient demographics, tumor characteristics, dose schemes, treatment responses, and complications. Patients with at least 6 months of follow-up data were included in the study. Results: Our review identified 29 evaluable patients (29 eyes) with vascular tumors of the eye, with the most common diagnosis being choroidal hemangioma (n Z 22). Additionally, three diffuse choroidal hemangiomas associated with Sturge-Weber syndrome, three retinal angiomas, and one hemangioblastoma associated with von Hippel-Lindau syndrome were also identified. The main analysis hereafter focuses on the choroidal hemangioma patients (n Z 22), with mean follow-up time of 78.5 months (range 12-177 months, median 69.2 months). Median age at diagnosis was 48.3 years (range 17-72). All 22 patients were symptomatic at the time of diagnosis. Initial tumor thickness, as measured by ultrasonography, ranged from 2.0 mm to 7.2 mm (mean 3.8 mm). All patients except one had the anterior tumor border located posterior to the equator. Patients were treated using total doses between 18 and 24 Cobalt Gray Equivalent (CGE) in four fractions. Best corrected visual acuity improved or remained stable in 20 of 22 eyes (91%). Of the 16 eyes initially presenting with retinal detachment, 15 experienced reattachment (94%). Cystoid macular edema was initially documented in 16 eyes and completely resolved in 13 eyes (81%). Subretinal fluid was initially present in 17 eyes and resolved in 16 eyes (94%). Tumor thickness decreased in all eyes as of last examination. Notable complications occurred in five patients, with the most common being radiation retinopathy and atrophy; anti-VEGF therapy was used for treatment. Nine patients received full dose to the disc and macula (range 18-24 CGE), none of whom had significant worsening of vision. The additional seven intraocular vascular tumors with variable histologies have also demonstrated tumor response after PBRT at mean follow-up of 29.5 months (median 24.4 months) with stable or improved visual acuity. Conclusions: This series demonstrates consistent and long-term tumor response and visual preservation in patients with benign vascular tumors of the eye, including choroidal hemangiomas, diffuse hemangiomas with Sturge-Weber syndrome, retinal angiomas, and hemangioblastoma related to von Hippel-Lindau syndrome. The data presented represents the longest available follow-up in the literature to date for choroidal hemangiomas treated with PBRT. Author Disclosure: E.M. Chang: None. D.H. Char: None. D. Jusufbegovic: None. I.K. Daftari: None. T.B. Cole: None. J.M. Quivey: None. T.L. Phillips: None. K.K. Mishra: None.