[Retinal intoxication with tamoxifen treatment for breast cancer]

Breast cancer is often treated with tamoxifen, a drug that can cause ocular side effects, including toxic retinopathy. Multimodal imaging, particularly optical coherence tomography (OCT), has improved the detection of early lesions such as foveal pseudocysts, thus increasing the prevalence of this complication. We present a case of tamoxifen-induced retinopathy in a patient treated for four years who developed decreased visual acuity with irreversible retinal lesions in the right eye despite discontinuation of the treatment. OCT was essential in characterizing the lesions. The pathophysiology remains poorly understood, but involvement of Müller cells and glutamate accumulation in the retinal pigment epithelium are suspected. Toxicity depends on cumulative dose, duration of treatment, and individual factors. Initial ophthalmologic screening and regular OCT monitoring are recommended to detect retinal damage early. In case of lesions, substitution with an aromatase inhibitor is often considered to limit lesion progression and preserve vision.