Visual Outcomes after Proton Therapy for Recurrent Uveal Melanoma

Abstract

Proton beam reirradiation remains an effective and globe-preserving alternative to enucleation in the treatment of local recurrence in uveal melanoma. The study aimed to assess visual outcomes and prognostic factors in visual acuity following proton beam salvage therapy. Retrospective study SUBJECTS: A retrospective study evaluated patients with recurrent uveal melanoma treated with proton beam irradiation (PBI) from 1984 through 2019 at a single academic tertiary center. Patient and tumor characteristics were collected from the medical record, as well as best visual acuity (BVA) and ocular outcomes following treatment of recurrent uveal melanoma with PBI. The primary outcome of the study was the visual acuity of patients following proton beam irradiation for recurrent uveal melanoma. Additional outcome measures included enucleation rate of patients following salvage PBI and analysis of tumor and patient characteristics in the prognostication of visual acuity. The study comprised 67 patients who received PBI for recurrent uveal melanoma. The median age at recurrence was 67.6 years (range 31.6-91.0 years) and median follow-up from the time of recurrence to last examination was 4.4 years (range 0.23-17.1 years). The median final BVA was hand motion (range 20/20-no light perception) and 6 (9.1%) patients maintained a Snellen VA 20/40 or better. The 5-year probability of visual acuity retention of 20/200 or better was 19%. In a multivariable Cox model, VA at tumor recurrence of less than 20/40 was found to be significantly associated with a VA of 20/200 or worse following retreatment with PBI. Twelve (18%) patients underwent enucleation following retreatment with PBI. PBI allows for ocular preservation and functional vision in the treatment of recurrent uveal melanoma in select patients.