Ocular toxicity in low-dose tamoxifen: a prospective study

Purpose To look at the incidence, symptomatology, course and reversibility of low-dose tamoxifen ocular toxicity. Methods Sixty-five women with breast cancer, on tamoxifen oral therapy (20 mg/day), and a totally normal eye examination, were prospectively followed up. A full ophthalmic evaluation was done every 6 months, for a median of 3 0 months (range 4-79 months). Any sign of toxicity in the cornea, lens, ret ina or optic nerve was looked for, whether associated with a change in visu al acuity or not. Results Ocular toxicity was documented in 8 patients, giving act incidence of 12%. Seven patients had keratopathy in the form of subepithelial deposit s, whorls and linear opacities. Three of these patients had a concurrent sy mptomatic bilateral pigmentary retinopathy that warranted discontinuation o f therapy. One patient developed bilateral optic neuritis that left her wit h optic nerve pallor and a decrease in vision. The patients who had the tox icity had a significantly higher tamoxifen cumulative dose (p = 0.03), and were longer on treatment (p = 0.04), than the nonaffected ones. The keratop athy changes were reversible upon discontinuation of the drug. Conclusion Prompt reporting of symptoms and yearly ophthalmic examinations are mandatory in patients on tamoxifen to detect toxic effects while these are still reversible.