Breast Cancer Medications and Vision: Effects of Treatments for Early-stage Disease

Abstract

This review concerns the effects on vision and the eye of medications prescribed at three phases of treatment for women with early-stage breast cancer (BC): (1) adjuvant cytotoxic chemotherapy, (2) adjuvant endocrine therapy, and (3) symptomatic relief. The most common side effects of cytotoxic chemotherapy are epiphora and ocular surface irritation, which can be caused by any of several different regimens. Most notably, the taxane docetaxel can lead to epiphora by inducing canalicular stenosis. The selective-estrogen-receptor-modulator (SERM) tamoxifen, long the gold-standard adjuvant-endocrine-therapy for women with hormone-receptor-positive BC, increases the risk of posterior subcapsular cataract. Tamoxifen also affects the optic nerve head more often than previously thought, apparently by causing subclinical swelling within the first 2 years of use for women older than ~50 years. Tamoxifen retinopathy is rare, but it can cause foveal cystoid spaces that are revealed with spectral-domain optical coherence tomography (OCT) and that may increase the risk for macular holes. Tamoxifen often alters the perceived color of flashed lights detected via short-wavelength-sensitive (SWS) cone response isolated psychophysically; these altered perceptions may reflect a neural-response sluggishness that becomes evident at ~2 years of use. The aromatase inhibitor (AI) anastrozole affects perception similarly, but in an age-dependent manner suggesting that the change of estrogen activity towards lower levels is more important than the low estrogen activity itself. Based on analysis of OCT retinal thickness data, it is likely that anastrozole increases the tractional force between the vitreous and retina. Consequently, AI users, myopic AI users particularly, might be at increased risk for traction-related vision loss. Because bisphosphonates are sometimes prescribed to redress AI-induced bone loss, clinicians should be aware of their potential to cause scleritis and uveitis occasionally. We conclude by suggesting some avenues for future research into the visual and ocular effects of AIs, particularly as relates to assessment of cognitive function.

Keywords::

• Aromatase inhibitor
• Dry eye
• Estrogen
• Retina
• Short-wavelength-sensitive cones
• Tamoxifen

ACKNOWLEDGMENTS

Portions of this work were supported by NIH grant EY014594 (to A. Eisner). We would like to thank Alison Conlin, MD, MPH, and David Sullivan, PhD, for critiquing the manuscript; and Linda Simmons, MLS, for help locating references.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

NOTICE OF CORRECTION

The Early Online version of this article published online ahead of print on 5 August 2011 contained errors.

1. The start of the Abstract on page 867 has been changed from “This review concerns the visual and ocular effects...” to “This review concerns the effects on vision and the eye...”

2. The original receipt date has been added at the bottom of page 867.

3. Capitalization has been corrected in the section heading on page 873.

These errors have been corrected for the current version.