Every clinic schedule is different. Different patient volumes, different demographics, and different exam types. However, in the past month you’ve more than likely encountered a cancer survivor or current cancer patient. For many optometrists, we read through the case history stopping to verify cancer type, diagnosis date, and ask if the patient is under current treatment.
When are these general questions not enough? I had never stopped to ask this question until I started seeing multiple breast cancer patients on a weekly basis. When this started happening, I wanted to understand the best way to differentiate a potentially metastatic complication from other retinal comorbidities.
Ophthalmic metastasis of breast cancer
Breast cancer is the most common neoplastic disorder diagnosed in women, with more than 250,000 cases diagnosed annually in the United States. With ocular involvement identified more often, it is important for clinicians to be familiar with possible ocular complications that may impact a patient’s vision.
Many reports on breast cancer fail to or only briefly mention the incidence of ocular metastasis; consequently limiting education and downplaying awareness for both patients and physicians. This, in turn, can leave patients unaware of potential symptoms, resulting in delayed diagnosis and treatment. Additionally, ocular diagnosis may be delayed if optometrists are not aware of key findings during the exam and fail to refer appropriately.
Prevalence of clinically evident uveal metastases in carcinoma patients ranges across literature, falling between two and nine percent. Of those patients, 71-92% of cases can be attributed to breast and lung cancer. Patients with a past history of breast cancer should specifically be screened since upwards of 85% of patients positive for ocular metastasis had a known history.3
While the incidence of ophthalmic metastasis of breast cancer is relatively rare, suspicious ocular lesions observed during an annual dilated fundus examination can have visually devastating effects. Due to the rarity of ocular manifestations from breast cancer (and other cancers in general), clinical indications are often glossed over in optometry school. This tends to lead to spending roughly five to ten minutes on a generalized overview.
As practicing optometrists, readily identifying clinical findings and remembering the necessary next steps can be difficult. This article is meant to serve as a simplified guide for general care optometry to readily recognize the signs and symptoms and to increase your confidence in the next steps of management.
Signs and symptoms
Patients can present with either visual changes or nonspecific symptoms. Most commonly, patients may notice vision distortions from metamorphopsia and/or changes in their visual field.3 Nonspecific symptoms such as photopsia or an increase in floaters have also been observed. Unfortunately, even a thorough chief complaint may not arouse suspicion. A 2007 evidence-based analysis of metastatic carcinoma of the uveal tract estimated a majority of patients with metastatic choroidal disease have no symptoms at all (~81% of uveal metastases).
Clinical manifestations are known to involve both the posterior and/or anterior segments. While incidence of metastasis varies across literature, general uveal involvement can be broken down as follows: choroid (88%), iris (9%) and ciliary body (2%). Typical presentation is unilateral, but bilateral involvement has been noted specifically in individuals with late-stage or aggressive cancer.
Choroidal disease is mainly located in the superotemporal quadrants appearing as a homogenous, creamy-yellow, plateau-shaped lesion spreading laterally across the choroid.6 Iris metastasis can be associated with secondary glaucoma and characteristically presents as rapidly growing yellow to white nodules most commonly noted in the mid-periphery of the inferior quadrant.7 Lastly, ciliary body metastases typically present as cyst-shaped or as a sessile mass in the inferior quadrant of the eye (25% of cases). Additional complications can include shallowing of the anterior chamber, lens subluxation, and cataracts.
Another consideration includes reviewing current treatments prescribed by oncology to screen for medication-induced ocular side effects. Individuals treated with radiation therapy may be at risk for early cataract development and dry eye.8 Pharmaceutical drugs should also raise a red flag. For instance, Tamoxifen is a selective estrogen receptor modulator and is commonly prescribed to patients in low dosages (20 mg - 40 mg QDay) to minimize adverse ocular effects. Ocular complications are rare, at an incidence of 0.6%, but can jump to 10.9% when used in conjunction with chemotherapy. Complications include cataracts, vortex keratopathy, crystalline maculopathy (primarily in the perifoveal area), and optic neuritis.9
Diagnostic testing for ophthalmic metastasis of breast cancer
A variety of diagnostic tests can be utilized to identify and monitor metastatic lesions. Optical coherence tomography can help reveal subretinal fluid and elevation of the retinal pigment epithelium. Fluorescein angiography imaging can be used to show hyperfluorescent masses in the late venous phase.10 B-scan echography, in conjunction with magnetic resonance imaging (MRI), is important in evaluating the characteristics of the lesion to differentiate between cancer metastases and primary ocular melanomas.3,10 One defining feature obtained from such scans is that primary ocular melanomas tend to have an average thickness of 5.5 mm compared to 2-3mm for breast cancer metastases.
Recommended Diagnostic Testing Overview:
- Slit lamp biomicroscopy
- Dilated fundus exam with an indirect ophthalmoscope
- Wide field fundus photos
- Fluorescein angiography
- Optical coherence tomography
- B-scan echography
Treatment and management
Optometrists should follow appropriate dilating guidelines for all patient populations to screen for unusual ocular lesions. However, as a general rule, all cancer survivors should be dilated on an annual basis. While ocular metastasis is relatively rare, clinicians should follow systematic diagnostic and management strategies to ensure timely treatment.
- If no suspicious lesion/ocular metastasis observed
- Survivors and patients currently in treatment are recommended to have annual dilated eye exams.
- Educate the patient on signs and symptoms of possible ocular changes including metamorphopsia, new onsets of blurred vision, and an increase in flashes and floaters.
- If suspicious lesion/ocular metastasis
- Immediate referral to ocular oncology.
- Depending on patient case, asymptomatic patients may be monitored while vision-threatening metastasis initiates therapy.
- A few of the most common therapies, cited by the American Academy of Ophthalmology, include radiation therapy, plaque radiotherapy, and hormonal therapy.
- If ocular metastasis presents unilaterally
- Patients to be followed every three to four months to monitor for changes with retinal specialist or ocular oncology.11
|Exam Findings||Treatment and Follow Up|
|Unilateral ocular metastasis||
- Watkins EJ. Overview of breast cancer. JAAPA. 2019;32(10):13-17.
- Kanthan GL, Jayamohan J, Yip D, Conway RM. Management of metastatic carcinoma of the uveal tract: an evidence-based analysis. Clin Exp Ophthalmol. 2007;35(6):553-565.
- Doran M. How to Spot Ocular Metastases. American Academy of Ophthalmology. https://www.aao.org/eyenet/article/how-to-spot-ocular-metastases. Published March 22, 2016. Accessed January 20, 2020.
- Shields CL, Shields JA, Gross NE, Schwartz GP, Lally SE. Survey of 520 eyes with uveal metastases. Ophthalmology. 1997;104(8):1265-1276.
- Park C, Sinha M, Shields CL. Breast Cancer Metastasis to the Eye: Facts and Figures. Retina Today. http://retinatoday.com/2010/03/breast-cancer-metastasis-to-the-eye-facts-and-figures/. Published March 2010. Accessed January 20, 2020.
- Demirci H, Shields CL, Chao AN, Shields JA. Uveal metastasis from breast cancer in 264 patients. Am J Ophthalmol. 2003;136(2):264-271.
- Shields JA, Shields CL, Kiratli H, de Potter P. Metastatic tumors to the iris in 40 patients. Am J Ophthalmol. 1995;119(4):422-430.
- Parsons JT, Bova FJ, Mendenhall WM, Million RR, Fitzgerald CR. Response of the normal eye to high dose radiotherapy. Oncology (Williston Park). 1996;10(6):837-847; discussion 847-838, 851-832.
- Gianni L, Panzini I, Li S, et al. Ocular toxicity during adjuvant chemoendocrine therapy for early breast cancer: results from International Breast Cancer Study Group trials. Cancer. 2006;106(3):505-513.
- Georgalas I, Paraskevopoulos T, Koutsandrea C, et al. Ophthalmic Metastasis of Breast Cancer and Ocular Side Effects from Breast Cancer Treatment and Management: Mini Review. Biomed Res Int. 2015;2015:574086.
- Finger P. Choroidal Metastasis " New York Eye Cancer Center. New York Eye Cancer Center. https://eyecancer.com/eye-cancer/conditions/choroidal-tumors/choroidal-metastasis/. Published March 1, 2019. Accessed January 20, 2020.