A case of tamoxifen keratopathy.

Tamoxifen citrate (ICI46474) is an antiestrogenic agent used in cases of disseminated breast carcinomas and as adjuvant postoperative therapy. Toxic reactions to tamoxifen, such as decreased visual acuity, bilateral macular edema, and yellow-white dots in the paramacular and foveal areas, are relatively rare (reported incidence between 0.9%-12%). In 1978, Kaiser-Kupfer and Lippman first reported the occurrence of what has become known as tamoxifen keratopathy and tamoxifen retinopathy in 4 women treated with very high doses (up to 320 mg per day) of tamoxifen citrate for longer than 1 year. The typical findings were bilateral white, whorl-like, central, subepithelial opacities in the cornea. They also found white refractive opacities superficial to retinal blood vessels, forming clusters located in the paramacular and foveal areas, with the highest concentration temporally, and clinical and angiographic evidence of cystoid macular edema. The keratopathy led to decreased visual acuity but was reversible on withdrawal of the drug, whereas the retinopathy, which also led to decreased visual acuity, was not reversible. Despite the decrease in the recommended dose of tamoxifen, retinopathy was reported in patients taking 40 mg of tamoxifen citrate per day and later in patients taking 20 mg of tamoxifen citrate per day. In the majority of cases, however, the toxic effects were reversible. Optic neuritis after tamoxifen use was reported as well.