What You Need to Know About Uveal Melanoma
Not the most pleasant of facts, but wherever there are cells in your body, there’s potential for cancer. With countless cells that help us see, the eyes are at risk for ocular melanoma, or more specifically, uveal melanoma (referring to where it commonly develops within the eye). There aren’t screenings for this cancer, but it can be found with an ophthalmic exam. And while it’s rare (5.1 cases per million adults a year), uveal melanoma doesn’t always have symptoms and is serious when it spreads, making it all the more important to see an eye doctor before trouble strikes. Here’s more about it.
What Is Uveal Melanoma?
Uveal melanoma is a primary cancer, meaning it starts in the eye. Other cancers can start elsewhere (like the breast and lungs) and spread to the eye—those are called secondary eye cancers, because they’re other cancer types that have metastasized. “Almost always when we see melanoma in the eye, we are pretty much assured that it started in the eye and is going somewhere else, not the other way around,” explains Raj Maturi, M.D., clinical spokesperson for the American Academy of Ophthalmology and associate professor at Indiana University School of Medicine, department of ophthalmology, in Indianapolis.
How Many People Have It?
Like we said, it’s a rare cancer. In the U.S. in 2020, an estimated 3,400 adults—1,890 men and 1,510 women—will be diagnosed with primary ocular cancer, the majority of which are uveal melanomas (other eye cancer types include Non-Hodgkin lymphoma in adults and retinoblastoma in children). The American Cancer Society estimates that of those, 390 people will die from eye cancer (scary, we know), so early detection is important—and new treatments could offer hope to those whose cancer has spread throughout the body, Dr. Maturi says.
Is Eye Melanoma the Same as Skin Melanoma?
While uveal melanoma and cutaneous (skin) melanoma share a name and develop from melanocytes, pigmentation cells that create melanin and color our skin, they’re biologically and genetically very different diseases, according to the National Organization for Rare Diseases. Skin melanomas are far more common, with 100,350 new cases estimated in the U.S. in 2020, and more than nine out of 10 melanomas starting in the skin.
Where Does Uveal Melanoma Happen in the Eye?
Ocular melanoma typically starts in the uvea/uveal tract, the middle of three layers of the eye. The uveal tract has three parts, any of which can develop melanoma: the iris (the color part of your eye surrounding the black pupil), choroid (pigmented tissue filled with blood vessels that provide oxygen and nutrients to the eye), and ciliary body (muscle fibers that change pupil size and lens shape). Uveal melanoma in the choroid (called choroidal melanoma) is the most common, accounting for 85% of uveal melanomas.
How Does it Develop in the Eye?
We’re looking at you, melanocytes. These cells, usually benign, can clump in your eye, creating a nevus, or freckle. Moles and freckles on your iris (and even on your skin) put you at higher risk for uveal melanoma, says Germame H. Ajebo, M.D., an oncologist and clinical assistant professor of medicine, hematology/medical oncology at Georgia Cancer Center-Downtown at University Hospital, in Augusta, GA. What triggers these cells to become malignant, we don’t know. “Freckles in the eye are common, just like freckles on our body,” Dr. Maturi elaborates. But as with freckles on your skin, a small percentage of those on your eye will turn cancerous.
What Are Other Risk Factors for Uveal Melanoma?
In addition to moles and freckles, fair skin and light eye color are common risk factors for ocular melanoma, Dr. Ajebo says. Age is another (55 is the average age at diagnosis) as is race, with Caucasians at higher risk than Blacks and Hispanics. A propensity to sunburn is another. Others are rare genetic conditions and ocular/oculodermal melanocytosis, a condition with a lifetime risk of approximately one in 400 of developing uveal melanoma. “Patients with this condition should undergo periodic ophthalmic examination to rule out uveal melanoma,” Dr. Ajebo points out.
Can You Prevent Uveal Melanoma?
While many risk factors of uveal melanoma are beyond your control, you can follow American Academy of Ophthalmology guidelines for healthy eye exams to detect eye cancer early. You should see an ophthalmologist—a medical or osteopathic doctor who differs from optometrists and opticians in additional years of medical training—for an eye exam once in your 20s and twice in your 30s. Older than that? Make an appointment, stat. You may need to go more often if you have any family history of eye diseases, or an eye disease that’s being followed.
What Are Some Symptoms of Uveal Melanoma?
Here’s the thing: Uveal melanoma can have no symptoms. It’s often discovered during a routine eye exam, Dr. Ajebo says. Approximately one-half of patients present with symptoms including: Flashes: You see flashes of light where there are no obvious light flashes in your environment. Floaters: These are spots that drift in and out of your field of vision. Visual field defects: Including a blind or dark spot in your vision. Changes: In the size or shape of the pupil or the eye’s position in its socket. These symptoms aren’t exclusive to uveal melanoma, so check with an ophthalmologist if you’re concerned.
How is It Diagnosed and Where Can it Spread?
Doctors often find uveal melanoma using specialized noninvasive techniques, like an ultrasound after numbing eye drops, Dr. Ajebo explains. In only about 5% of cases or less, you’d need a diagnostic biopsy to confirm. After diagnosis, further testing determines if the cancer has spread, or metastasized. If uveal melanoma does spread, it’s most likely to go to the liver (in 80% of cases), which can be detected by reading your liver enzyme levels with lab testing and/or MRI/PET scan of the liver, Dr. Maturi says.
What’s the Prognosis?
The five-year relative survival rate (meaning the percentage of people alive 5 years after diagnosis) for ocular melanoma is 85% if the cancer hasn’t spread, and 71% if it’s spread to surrounding tissues or organs and/or regional lymph nodes. Spread to distant parts of the body drops the 5-year survival rate to 13%—but only 2% to 3% of primary eye cancer is diagnosed at this stage. One bright spot: Earlier detection and new treatment options could increase survival rates, experts say.
What Are the Treatments for Uveal Melanoma?
One effective treatment is radioactive plaque brachytherapy, according to a key study, the Collaborative Ocular Melanoma Study (COMS). A plaque is placed on your eye for about a week to release radiation that “melts” the uveal melanoma. “The one thing we can do is save the eye in a vast majority of cases,” Dr. Maturi says. Whether you experience vision loss depends on the size of the melanoma. Surgically removing your eye, called enucleation, was once common, but radiation therapy has reduced its use. Enucleation is still done for large tumors, but now there are additional treatment options, like external-beam radiation, charged-particle therapy, and gamma-knife radiosurgery.
Is Immunotherapy Useful in Uveal Melanoma?
In the last decade, breakthroughs in immunotherapy have changed how cutaneous melanoma is treated. But because melanoma of the eye and skin are not biologically the same cancer, it’s been a challenge to find new treatments that work for both. One human monoclonal antibody approved for advanced cutaneous melanoma has shown promise in treating uveal melanoma. Yet most of these new medications have “very modest activity” in uveal melanoma, a 2019 article in Clinical Advances in Hematology & Oncology reports. More research is needed, making clinical trials a vital part of finding effective treatments, Dr. Ajebo says.
Who Diagnoses and Treats Uveal Melanoma?
Uveal melanoma is commonly diagnosed by a general ophthalmologist. The uveal tract is often treated by retina specialists, so you’ll likely be referred to one, Dr. Maturi says. Retina specialists commonly work with radiation oncologists to administer radioactive plaque brachytherapy. If you need an enucleation, an oculoplastic surgeon would typically remove the eye and fit you with an ocular prosthesis, or artificial eye.
What Happens After Treatment?
Here’s the thing: If your treatment for early uveal melanoma (which has stages 1-4 for ciliary body and choroid melanomas, but no staging for iris melanoma) is effective, you still have a 50% risk of metastasis. Though that might not happen for a while: “The appearance of metastases may be delayed for a prolonged period, suggesting that long-term surveillance is needed to detect late recurrences,” Dr. Ajebo says. So your ophthalmologist should follow you for life, Dr. Maturi says. Your doctor will continue to monitor your liver lab results too, to ensure the cancer hasn’t spread.