While malignant melanoma of the eye is quite rare — only about 2,500 cases are reported in the U.S. each year — precursors of this disease are quite common. One in 10 Caucasians will develop a mole under the retina (known as a “choroidal nevus”) during their lifetime.
“Many [moles in the eye] are benign and very low risk,” said Dr. Scott Walter of the Hartford HealthCare Cancer Institute’s Melanoma and Skin Cancer Center. “But some have higher risk characteristics and could transform into a true melanoma.”
Dr. Walter is one of two ocular oncologists practicing in Connecticut. He is the only one also trained as a retinal surgeon.
Dr. Walter focuses on tumors in the back of the eye that require the expertise of a retina specialist to manage effectively. He treats patients with uveal melanoma, the most common cancer that originates in the eye; cancers elsewhere in the body that have spread to the eye (most frequently breast and lung cancer); along with other mostly benign tumors that originate in the eye.
Sometimes a biopsy is required to confirm a diagnosis of eye cancer.
“I think it’s important to see a specialist who is comfortable performing a biopsy in such a sensitive location,” Walter said.
Most eye tumors develop under the retina, a delicate layer of tissue lining the inside of the eye that is responsible for vision. Minimally invasive biopsy methods and new molecular tests enable doctors to identify patients at risk of developing metastasis (spread of the disease to other organs). Early detection is key.
“The cancer is less likely to have spread if we catch it early,” said Dr. Walter.
Many people with eye melanoma don’t have symptoms until the cancer becomes more advanced. According to the American Cancer Society (ACS), signs and symptoms of eye melanomas can include blurry vision or loss of vision, shimmering sparkles or flashes of light, a growing dark spot on the colored part of the eye (iris), and changes in the size and shape of the pupil.
According to Dr. Walter and the ACS, risk factors for eye melanoma include:
- Race/ethnicity: The risk of intraocular melanoma is much higher in Caucasians and white Hispanics than in African Americans or Asian Americans.
- Eye color: People with blue, green, or hazel eyes are somewhat more likely to develop melanoma of the eye than are people with brown eyes.
- Age: Eye melanomas can occur at any age, but the risk goes up as people get older.
- Certain inherited conditions: People with oculodermal melanocytosis (darker pigmentation around the eye), dysplastic nevus syndrome(many abnormal moles on the skin), or a family history of certain rare cancers (mesothelioma, renal cell carcinoma, and/or melanomas on non-sun exposed regions) may be at increased risk of developing eye melanoma.
Routine eye exams can help to stop the disease in its tracks. Patients found to have a mole under the retina should have a dilated eye exam every six to 12 months to monitor the condition. Those with symptoms or high-risk features should be referred to an ocular oncology specialist for further evaluation.