Electroretinographic and optical coherence tomography findings in breast cancer patients using aromatase inhibitors

Partially Reversible Bilateral Papilledema in a Patient Using Anastrozole: A Case Study

Anastrozole is an endocrine-modifying agent used in the treatment of estrogen-sensitive breast cancer in the postmenopausal breast cancer population. Anastrozole is known for its side effect profile which includes an increased risk of osteoporosis. However, emerging evidence in the literature in the form of case studies demonstrates several potential ocular side effects due to the use of the medication. In our study, a 66-year-old female using anastrozole suffered severe bilateral papilledema that resolved after cessation of the medication. There is a growing body of evidence demonstrating the use of anastrozole and its impact on ocular health leading to deleterious side effects, such as papilledema.

A case report of cystoid macular edema, uveitis and vitreomacular traction in a patient taking Anastrozole

Purpose

To report a case of cystoid macular edema, uveitis, and vitreomacular traction in a patient with a history of breast cancer and taking anastrozole.

Observations

A 73-year-old female with a history of estrogen receptor-positive breast cancer and treatment with anastrozole presented with bilateral blurry vision, photophobia, and eye soreness. Optical coherence tomography (OCT) of both maculae revealed vitreomacular traction (VMT), an epiretinal membrane, cystoid macular edema (CME) in the right eye, and drusen without subretinal fluid bilaterally. Although later, macular OCT did show evidence of cystoid intraretinal spaces in the left eye as well. Fluorescein angiography showed bilateral petaloid leakage, bilateral slow disc leaking, as well as peripheral leakage in the right eye. Anastrozole was discontinued and, subsequent macular OCT showed release of VMT in the right eye, and eventual resolution of intraretinal cystoid spaces bilaterally.

Conclusions and importance

Stopping of anastrozole was associated in resolution of refractory CME in a patient on aromatase inhibitor therapy for breast cancer. It is therefore important to consider anastrozole and other aromatase inhibitor drugs as possible factors predisposing patients to the development of CME.

Ocular Side Effects of Aromatase Inhibitor Endocrine Therapy in Breast Cancer - A Review

BACKGROUND

Aromatase inhibitor therapy is currently the preferred choice in postmenopausal women with estrogen receptor positive breast cancer. This article reviews the ocular side effects of treatment with aromatase inhibitors (AIs) in patients with breast cancer.

MATERIALS AND METHODS

A comprehensive search was performed on PubMed, Web of Science and Google scholar.

RESULTS

After duplication removal, 14 clinical studies and 5 case reports, published between 2008 and 2021, were identified. Most frequently, AI treatment resulted in minor to moderate dry eye symptoms. "De novo" onset of Sjogren syndrome during AI therapy was also reported. Retinal and optic nerve side effects varied from mild, subclinical anatomic and functional impairment to severe decreased vision, secondary to hemi-central retinal artery occlusion, bilateral optic neuritis or uveitis with bilateral macular edema.

CONCLUSION

Visual disturbances encountered during AI treatment may be underestimated. Ophthalmic screening is important for early detection and appropriate treatment.

Aromatase in the Human Brain

The aromatase cytochrome P450 (P450arom) enzyme, or estrogen synthase, which is coded by the CYP19A1 gene, is widely expressed in a subpopulation of excitatory and inhibitory neurons, astrocytes, and other cell types in the human brain. Experimental studies in laboratory animals indicate a prominent role of brain aromatization of androgens to estrogens in regulating different brain functions. However, the consequences of aromatase expression in the human brain remain poorly understood. Here, we summarize the current knowledge about aromatase expression in the human brain, abundant in the thalamus, amygdala, hypothalamus, cortex, and hippocampus and discuss its role in the regulation of sensory integration, body homeostasis, social behavior, cognition, language, and integrative functions. Since brain aromatase is affected by neurodegenerative conditions and may participate in sex-specific manifestations of autism spectrum disorders, major depressive disorder, multiple sclerosis, stroke, and Alzheimer's disease, we discuss future avenues for research and potential clinical and therapeutic implications of the expression of aromatase in the human brain.

Review of the Literature on Ocular Complications Associated With Aromatase Inhibitor Use

Aromatase inhibitors (AIs), such as anastrozole, letrozole, and exemestane, are commonly used as adjuvant endocrine therapy in hormone-receptive breast cancer in postmenopausal women. Their adverse effects are well documented, except for visual disturbances. The purpose of this study was to review the current literature on ocular disease linked to AI use. Due to the scarcity of published data, any suggested ophthalmic adverse events were included to increase awareness of these drugs. The ocular side effects of tamoxifen use are well documented and were not included. Cases of rare side effects such as papilloedema, macular oedema, and uveitis associated with anastrozole and letrozole have been reported. Studies demonstrating retinopathy, in the form of crystalline retinopathy, hemicentral retinal artery occlusion, and retinal haemorrhages, are also noted. All three third-generation AIs can also lead to ocular surface diseases such as corneal epithelial changes, blepharitis, and keratitis. There is slightly more literature available regarding anastrozole-related ocular diseases. Although these are likely rare side effects, we recommend a high level of clinical suspicion when assessing patients with visual symptoms and on AIs. Larger prospective studies are necessary to further investigate these complications.

Genome-wide association analyses identify 139 loci associated with macular thickness in the UK Biobank cohort

The macula, located near the center of the retina in the human eye, is responsible for providing critical functions, such as central, sharp vision. Structural changes in the macula are associated with many ocular diseases, including age-related macular degeneration (AMD) and glaucoma. Although macular thickness is a highly heritable trait, there are no prior reported genome-wide association studies (GWASs) of it. Here we describe the first GWAS of macular thickness, which was measured by spectral-domain optical coherence tomography using 68 423 participants from the UK Biobank cohort. We identified 139 genetic loci associated with macular thickness at genome-wide significance (P < 5 × 10-8). The most significant loci were LINC00461 (P = 5.1 × 10-120), TSPAN10 (P = 1.2 × 10-118), RDH5 (P = 9.2 × 10-105) and SLC6A20 (P = 1.4 × 10-71). Results from gene expression demonstrated that these genes are highly expressed in the retina. Other hits included many previously reported AMD genes, such as NPLOC4 (P = 1.7 × 10-103), RAD51B (P = 9.1 × 10-14) and SLC16A8 (P = 1.7 × 10-8), further providing functional significance of the identified loci. Through cross-phenotype analysis, these genetic loci also exhibited pleiotropic effects with myopia, neurodegenerative diseases (e.g. Parkinson's disease, schizophrenia and Alzheimer's disease), cancer (e.g. breast, ovarian and lung cancers) and metabolic traits (e.g. body mass index, waist circumference and type 2 diabetes). Our findings provide the first insight into the genetic architecture of macular thickness and may further elucidate the pathogenesis of related ocular diseases, such as AMD.

The role of optical coherence tomography in therapeutics and conditions, which primarily have systemic manifestations: a narrative review

Optical coherence tomography is designed to evaluate in vivo qualitative and quantitative changes of the anterior segment, optic nerve and the retina. Initial applications of this technology were confined mainly to ophthalmic diseases. However recently, numerous studies have evaluated its use in systemic conditions and in therapeutics where, optic nerve and retinal architecture can be assessed to monitor progression of systemic conditions and its response to treatment. This is a narrative review aimed at evaluating the debate surrounding the role of spectral domain optical coherence tomography, in systemic conditions where optic nerve affection can be measured and be used in the diagnosis, monitoring and assessment of treatment effect as a non-invasive, quick, novel technique.

Ocular Surface Disease in Breast Cancer Patients Using Aromatase Inhibitors

Aromatase inhibitors (AIs) are widely used as adjuvant hormonal therapy in postmenopausal women with hormone receptor-positive breast cancer. The purpose of this study was to investigate the potential impact of AIs on the anterior segment of the eye and especially the ocular surface. Participants in our study were 41 hormone receptor-positive early stage breast cancer patients (80 eyes), treated with AIs, while 80 eyes of 40 age- and gender-matched healthy controls, not previously used AIs for any purpose, were also evaluated. All participants underwent a complete ophthalmological examination, including best corrected visual acuity (BCVA) assessment, slit-lamp biomicroscopy, and dilated fundus examination. Ocular surface disease-related symptoms and signs were also recorded. The most common symptom was found to be blurred vision, while other symptoms included foreign body sensation, tearing, redness, and photophobia. Slit-lamp examination revealed blepharitis and meibomian gland dysfunction in 75% and 42.5% of patients, respectively. Superficial punctate keratitis and conjunctival injection were also present. Our results demonstrated a high prevalence of ocular surface disease-related symptoms and signs in patients receiving AIs compared to healthy controls. This study may raise a flag regarding the use of AIs. However, further and larger prospective longitudinal studies are needed to examine the possible effect of AIs alone or in combination with chemotherapy in the eyes of breast cancer patients.