An Ophthalmologist Guides Oncologists and Patients Through ADC-Related Eye Toxicities: With Sara Nunnery, MD, MSCI; and Sarah Sunshine, MD

Breast Cancer Briefing, hosted by Sara Nunnery, MD, MSCI, a breast medical oncologist and the director of Breast Cancer Research at Tennessee Oncology in Nashville, is a podcast series that breaks down the latest news in breast cancer research, one conversation at a time.

In this episode, Dr Nunnery sat down with Sarah Sunshine, MD, an ophthalmologist and assistant professor of ophthalmology at the University of Maryland School of Medicine in Baltimore, whose research focuses on the ocular adverse effects associated with cancer drugs.

The experts discussed how breast cancer therapies affect the eye, beginning with a primer on ocular anatomy. Dr Sunshine explained that the cornea and the broader ocular surface are where many antibody-drug conjugate (ADC)–associated toxicities manifest, and she noted that different drug classes can affect distinct structures, causing dry eye, macular edema, or uveitis. She observed that conventional cytotoxic chemotherapy can also produce dry eye, which is usually reversible with treatment.

The conversation then addressed photopsia, the flashing-light phenomenon seen with the selective estrogen receptor degrader camizestrant. Dr Sunshine emphasized that these events do not damage the retina but stressed that any patient reporting flashing lights requires a dilated eye examination to rule out a retinal tear or detachment.

Turning to ADCs, Dr Sunshine cautioned that these agents are not uniform in the ocular toxicities they are associated with, contrasting the severe corneal effects seen with belantamab mafodotin-blmf (Blenrep) with the milder, less frequent toxicity of breast cancer ADCs, such as datopotamab deruxtecan-dlnk (Dato-DXd; Datroway). She characterized Dato-DXd’s corneal toxicity as dry eye, possibly involving limbal stem cells, and detailed prevention and monitoring strategies, including using preservative-free artificial tears at least 4 times daily, undergoing a baseline comprehensive examination, and following up for eye evaluations during subsequent treatment cycles.

Finally, Dr Sunshine reviewed red-flag symptoms warranting patient referral to eye care specialists, distinguished optometrists from ophthalmologists, and emphasized ADC-specific eye examination forms, timely communication, and strong oncology/eye care partnerships as central to preventing permanent vision damage.