Abstract
Purpose :
Combined iridectomy and proton beam radiotherapy has been previously reported for the treatment of non-resectable iris melanomas. However, no previously published case series reports the combination of surgical resection and plaque radiation therapy. The purpose of this study is to report our results of combined surgical resection and Iodine-125 plaque brachytherapy for the treatment of iris melanoma.
Methods :
This is a retrospective case series of 7 patients with iris melanoma treated with combined iridectomy and plaque brachytherapy between 2002 and 2018. Main outcomes include tumor regression, metastatic disease, post-operative visual acuity, post-operative intraocular pressure, and complications.
Results :
Seven patients (median age: 46.0) with iris melanomas were treated with partial excision followed by iodine-125 plaque brachytherapy. Patients presented with growth of a previously noted lesion (n=5), eye pain (n=1) or secondary pigmentary glaucoma (n=1). The average tumor area was 61.5 mm2 and involved 2.5 clock hours. Tumor frequently involved the angle (n=5), corneal endothelium (n=2), and ciliary body (n=6). The average time from resection to brachytherapy was 1.35 months. Median follow-up time was 115.1 months (range, 12.9 to 140.2).Two patients had recurrence of their melanoma, one of which required subsequent enucleation. Metastasis was not observed in any patient, and there was no disease specific mortality. After treatment, the average intraocular pressure decreased from 16.1mmHg to 12.5mmHg. Visual acuity decreased in every patient (preoperative mean logMAR visual acuity: 0.41; postoperative: 1.51). Decreased visual acuity was attributed to corneal scarring (n=2), glaucoma (n=3), cataract development (n=1) or idiopathic (n=2). Most patients reported dry eye symptoms (n=5). Other complications included sceleromalacia (n=1) and anterior uveitis (n=1).
Conclusions :
Iridectomy with plaque brachytherapy appears to be an acceptable treatment option for non-resectable iris melanomas, resulting in excellent tumor control and a rate of complications comparable with existing treatment regimens. Longer follow-up studies on a larger series is necessary.
This is a 2020 ARVO Annual Meeting abstract.