Early-Onset Posterior Subcapsular Cataract After Short-Term Tamoxifen Therapy In A Young Patient Without Retinal Toxicity

To report a case of early-onset posterior subcapsular cataract associated with tamoxifen therapy in a young patient and to examine its clinical relevance for cataract surgery and anterior segment monitoring in the absence of retinal toxicity or other established cataract risk factors.

Department of Ophthalmology, University Hospital Center Osijek, Croatia, a tertiary referral center.

A 39-year-old woman presented with two months of progressive blurred distance vision in the right eye, without other visual complaints. Two years earlier, she had been diagnosed with HER2–positive invasive breast carcinoma and had undergone segmentectomy followed by adjuvant therapy including trastuzumab (the first 12 months after surgery) and tamoxifen (for the past 22 months). The disease remained in remission, and systemic findings were unremarkable. Best-corrected visual acuity was 0.8 in the right eye and 1.0 in the left eye. Color vision (Ishihara plates) and contrast sensitivity (Pelli-Robson chart) were normal. Ocular motility and pupils were normal, with no RAPD. Slit-lamp examination revealed posterior subcapsular punctate lens opacities in the right eye and minimal nasal posterior subcapsular changes in the left eye; the remaining anterior segment findings were unremarkable. Lens opacities were graded according to the Lens Opacities Classification System III (LOCS III): right eye NC1 NO1 C2 P2; left eye NC1 NO1 C1 P2. There was no history of diabetes, corticosteroid use, trauma, radiation exposure, other cataract risk factors, or family history of early-onset cataract. Optical coherence tomography demonstrated normal macular architecture without signs of tamoxifen-associated retinal toxicity. Given the visually significant lens opacification, phacoemulsification with posterior chamber intraocular lens implantation was advised; however, the patient deferred surgery.

Tamoxifen therapy may be associated with early posterior subcapsular lens opacification in young patients after relatively short exposure, even in the absence of established cataract risk factors. Although primarily recognized for crystalline retinopathy and macular changes, tamoxifen-related lens opacification may represent an underrecognized anterior segment manifestation. This case suggests that visually significant cataract may occur sooner than anticipated in patients receiving this widely used therapy. Regular anterior segment evaluation during follow-up is therefore advisable, as lens changes may influence cataract surgery planning and referral.