Radiotherapy has little benefit in AMD

NEW YORK — Radiotherapy has a “short-lived and modest” benefit in patients with subfoveal choroidal neovascularization (CNV) and therefore has limited indications as a primary treatment for the condition, said Dennis M. Marcus, MD, speaking here.

Dr. Marcus presented 1-year results of the Age-related Macular Degeneration Radiotherapy Trial, a 10-center prospective study, here at the American Society of Retina Specialists’ annual meeting. He said there is no reason to pursue radiotherapy as a primary treatment, but that it may have indications as a adjuvant therapy.

In the study, sponsored by the National Eye Institute, 89 patients underwent external beam radiation, sham treatment or no treatment. All patients had baseline visual acuity of 20/320 or better with new CNV or with recurrent CNV that had not responded to laser treatment.

In the short term, 25% of patients with new CNV and 33% of patients with recurrent CNV lost three or more lines of visual acuity after radiotherapy. By comparison, 48% of new CNV patients and 50% of recurrent CNV patients lost three or more lines without treatment.

By 12-month follow-up, however, 43% of treated eyes and 50% of untreated eyes had lost at least three lines of visual acuity.

The eyes appeared similar under fluorescein angiography; 84% had occult CNV, 74% had CNV comprised of less than 25% blood and 81% had less than 25% fibrosis.

Only one eye receiving radiation exhibited multiple cotton wool spots and possible radiation retinopathy, according to the study.