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.

The mystery of angiographically silent macular oedema due to taxanes

“…Absence of both fluorescein leakage as well as late hyperfluorescence indicate that there is no inflammatory capillary leakage to explain the presence of subretinal fluid. In support of this are several additional observations: (1) there were no vitreous cells to be seen, (2) there was no subclinical inflammation detected by laser flare photometry which always showed normal values, (3) anti-inflammatory treatment associating steroid and non-steroidal drops had no effect whatsoever on the oedema, and (4) nine and 14 months after the resolution of the bilateral oedemas the right and left cataract were operated, respectively, which failed to produce neither CMO nor OCT thickening of the maculas, showing that the patient's maculas were not prone to develop inflammatory oedema.…”

“…Taxanes [paclitaxel (Taxol Ò ), docetaxel (Taxotere Ò ), and protein-bound paclitaxel (Abraxane Ò )] are widely used anticancer agents produced by the plants of the genus Taxus (yews) [1,2]. Their main mechanism of cytotoxic action is based on the stabilisation of microtubules leading to cell mitotic inhibition [2,3].…”

“…Their main mechanism of cytotoxic action is based on the stabilisation of microtubules leading to cell mitotic inhibition [2,3].…”

Sex, Eyes, and Vision: Male/Female Distinctions in Ophthalmic Disorders

“…52 That article discusses some of the essential distinctions between tamoxifen, which is a selective estrogen receptor modulator (SERM), and AIs, which are more aptly described as anti-estrogens. This distinction between SERMs and AIs is important and too often confused.…”

Oestrogen, ocular function and low-level vision: a review

“…Hormone receptor-positive breast cancer is typically treated pharmacologically using selective ER modulators (SERMs), such as tamoxifen, or aromatase inhibitors, such as anastrozole. Both treatments act by reducing the effects of oestrogen and both have been shown to produce visual (Eisner & Luoh 2011) and possibly some cognitive (Espeland et al 2010) side effects. Tamoxifen is a selective ER antagonist.…”