Few patients get eye exams after starting tamoxifen

Clinical takeaway: Consider discussing potential ocular adverse effects when initiating tamoxifen and encourage prompt ophthalmic evaluation for new visual symptoms. Despite known risks of tamoxifen-associated retinal toxicity, routine ophthalmic monitoring appears uncommon in clinical practice.

Tamoxifen remains a cornerstone endocrine therapy for hormone receptor-positive breast cancer, but it has been associated with retinal toxicity, including crystalline maculopathy and cystoid macular edema, and some changes may be irreversible. No formal US screening guidelines exist, leaving uncertainty about how patients should be monitored.

In a retrospective cohort study using data from the All of Us Research Program, a National Institutes of Health initiative that gathers health records and other data from a diverse group of participants across the US, investigators evaluated ophthalmic care patterns among 2,327 adults who initiated tamoxifen and had at least 12 months of follow-up.

Within 1 year of starting treatment, only 162 patients (7.0%) had any ophthalmic encounter, while just 39 patients (1.7%) underwent retinal-specific testing with optical coherence tomography or fundus photography.

Patients with preexisting glaucoma or diabetic retinopathy were more likely to receive ophthalmic care than those without either condition (25.0% vs 6.3%). Older age and greater healthcare utilization before tamoxifen initiation were also associated with higher rates of eye care.

To assess whether tamoxifen itself prompted increased monitoring, researchers compared patients with breast cancer receiving tamoxifen with those initiating aromatase inhibitors. Ophthalmic encounters occurred in 6.7% of patients taking tamoxifen vs 8.5% of those taking aromatase inhibitors. After adjustment for demographic and clinical factors, tamoxifen use was not associated with increased ophthalmic utilization.

The findings suggest that most ophthalmic care occurring after tamoxifen initiation is incidental rather than part of a structured surveillance strategy. In an accompanying editorial, Seong Joon Ahn, MD, PhD, noted that tamoxifen’s potential for retinal toxicity warrants clearer guidance on appropriate retinal surveillance.

“Additional evidence on retinopathy incidence, natural history, screening strategies, and clinical benefit is needed to inform guidance,” the authors wrote.

Source: Gandhi S, et al. (October 29, 2026) JAMA Ophthalmol. Ophthalmic Encounters After Tamoxifen Initiation