Clinical Scorecard: Reducing the Risk of Radiation Retinopathy

At a Glance

Key Highlights

• Radiation retinopathy typically manifests 6 months to 3 years post-treatment and is a leading cause of vision loss after plaque brachytherapy.
• Emerging strategies focus on prevention including reducing radiation dose, genetic risk stratification, systemic therapies, and prophylactic intravitreal anti-VEGF treatment.
• Current management parallels diabetic retinopathy treatments but prophylactic approaches and novel therapies may improve visual outcomes and reduce incidence.

Guideline-Based Recommendations

Diagnosis

• Monitor for clinical signs indistinguishable from diabetic retinopathy such as intraretinal hemorrhages, cotton wool spots, macular edema, and vascular nonperfusion starting 6 months post-radiation.

Management

• Use anti-VEGF injections and panretinal photocoagulation to treat established radiation retinopathy.
• Consider reducing radiation dose from standard 85 Gy to approximately 63 Gy to lower risk and severity of retinopathy.
• Employ custom-designed plaques to minimize radiation exposure to healthy retina.
• Utilize genetic tumor profiling to identify low metastatic risk tumors that may defer or avoid radiation.
• Investigate systemic neoadjuvant therapies such as darovasertib to shrink tumors pre-radiation and reduce radiation dose needed.
• Explore non-radiation treatments like belzupacap sarotalocan (bel-sar) activated by laser as alternatives to radiation.

Monitoring & Follow-up

• Regular ophthalmic follow-up post-radiation for early detection of retinopathy signs.
• Monitor visual acuity and retinal status during prophylactic intravitreal anti-VEGF treatment protocols.

Risks

• Vision loss can progress to 20/200 or worse within 3 years if radiation retinopathy develops.
• Radiation dose and plaque size/placement influence risk of retinal damage.
• Delaying or avoiding radiation based on tumor genetics must balance metastatic risk.

Patient & Prescribing Data

Patients undergoing plaque brachytherapy for primary choroidal melanoma

Prophylactic intravitreal anti-VEGF injections every 4 months for 2 years have shown improved median visual acuity (20/70 vs counting fingers) at 4 years compared to historical controls; randomized trials are ongoing to confirm efficacy.

Clinical Best Practices

• Incorporate genetic risk stratification to guide radiation necessity and dosing.
• Use custom plaque designs to limit retinal radiation exposure.
• Consider neoadjuvant systemic therapies to reduce tumor size before radiation.
• Implement prophylactic intravitreal anti-VEGF therapy prior to clinical retinopathy onset to preserve vision.
• Participate in or follow results from ongoing randomized trials (e.g., DRCR Retina Network Protocol AL) to refine preventive strategies.

References

• Kheir WJ et al. Preliminary results of uveal melanoma treated with iodine-125 plaques: analysis of disease control and visual outcomes with 63 Gy to the target volume. Adv Radiat Oncol. 2022
• (Neo)Adjuvant IDE196 (darovasertib) in patients with localized ocular melanoma. ClinicalTrials.gov NCT05907954
• Phase 3 trial of belzupacap sarotalocan (AU-011) for small choroidal melanoma. ClinicalTrials.gov NCT06007690
• Shields CL et al. Visual outcome at 4 years following plaque radiotherapy and prophylactic intravitreal bevacizumab. JAMA Ophthalmol. 2020