Eye cancer is a rare group of malignancies that develop in or around the eye. The most common type in adults, uveal melanoma, occurs in roughly 5 out of every million people per year. In children, retinoblastoma is the primary concern. While rare, eye cancers range widely in severity, and outcomes depend heavily on the type, location, and how early the disease is caught.
Types of Eye Cancer
Eye cancers fall into two broad categories based on where they start. Intraocular cancers grow inside the eyeball itself. Adnexal cancers develop in the surrounding structures: the eyelids, the tear glands, the eye socket, or the thin membrane covering the white of the eye (the conjunctiva).
The most common primary intraocular cancer in adults is uveal melanoma, which forms in the pigmented layer of the eye called the uvea. This layer has three parts: the iris (the colored ring you see in the mirror), the choroid (a blood vessel layer at the back of the eye), and the ciliary body (a ring of tissue behind the iris that helps the eye focus). Choroidal melanoma is by far the most frequent subtype. Iris and ciliary body melanomas are much less common.
A rarer intraocular cancer is primary intraocular lymphoma, a type of non-Hodgkin lymphoma closely linked to central nervous system lymphoma. Between 56 and 90 percent of people with this eye lymphoma eventually develop brain involvement, making it a cancer that requires monitoring well beyond the eye.
On the adnexal side, common cancers include basal cell carcinoma and squamous cell carcinoma of the eyelid, melanoma of the conjunctiva, and lymphomas of the eye socket. Cancers of the tear gland, while rare, tend to be aggressive.
Retinoblastoma in Children
Retinoblastoma is the most common eye cancer in children, and most are diagnosed before age 3. It starts in the retina, the light-sensing layer at the back of the eye, when a gene called RB1 mutates and causes retinal cells to multiply uncontrollably.
The earliest and most recognizable sign is leukocoria, a white glow in the pupil. Parents often first notice it in flash photographs taken in dim light, where one eye reflects red (the normal “red eye” effect) and the other appears white. Other signs include eyes that don’t look in the same direction, redness, or swelling. Because young children can’t describe vision problems, these visual cues from parents or pediatricians are critical for early detection.
Symptoms of Uveal Melanoma
Up to 30 percent of adults with uveal melanoma have no symptoms at all when the tumor is discovered during a routine eye exam. When symptoms do appear, they vary by location.
Choroidal melanoma, the most common form, can cause flashes of light, floating specks in your vision, blurry vision in one eye, or a shrinking field of side vision. Vision loss tends to happen when the tumor sits near the macula (the central part of the retina responsible for sharp sight) or when fluid builds up beneath the retina.
Ciliary body melanoma may push the lens out of position, causing blurry or distorted vision, and can raise pressure inside the eye. Iris melanoma is often the least symptomatic. It typically shows up as a growing dark spot on the colored part of the eye, sometimes noticed by the person in a mirror or by someone else.
Risk Factors
Uveal melanoma is more common in people with lighter eye colors, fair skin, and the ability to sunburn easily. Incidence rates reflect this pattern geographically: Australia and northern Europe report the highest rates (up to 7.6 and 10 per million, respectively), while countries like South Korea report rates below 0.5 per million.
A genetic condition called BAP1 tumor predisposition syndrome significantly raises the risk. People who carry mutations in the BAP1 gene face elevated odds of developing uveal melanoma along with several other cancers. Age is also a factor. Uveal melanoma most commonly appears in middle-aged and older adults.
How Eye Cancer Is Diagnosed
Ophthalmologists can often identify intraocular tumors without a surgical biopsy, using a combination of imaging tools. B-scan ultrasound, which operates at 10 to 20 MHz, allows doctors to see the shape, size, and borders of a tumor at the back of the eye. Uveal melanoma, for instance, characteristically appears as a dome or mushroom-shaped mass on ultrasound. Retinoblastoma shows distinctive calcium deposits that light up as bright spots on the image.
For tumors in the front of the eye, such as those on the iris or ciliary body, a higher-frequency ultrasound called ultrasound biomicroscopy provides detailed images of the smaller structures. Doppler ultrasound can map blood flow within a tumor, which helps distinguish cancerous growths from benign ones. Additional tools include optical coherence tomography (a high-resolution scan of retinal layers) and fluorescein angiography, which highlights abnormal blood vessels by injecting a dye that travels to the eye.
In some cases, a small tissue sample is needed. But for many intraocular tumors, the combination of clinical exam and imaging is accurate enough to begin treatment without biopsy.
Treatment Options
Treatment depends on the tumor’s type, size, and location, as well as whether it has spread. For many uveal melanomas, the goal is to destroy the tumor while preserving the eye and as much vision as possible.
The most widely used eye-preserving treatment is plaque brachytherapy. A small radioactive disc, typically containing Iodine-125 or Ruthenium-106 seeds, is surgically stitched to the outside of the eye directly over the tumor. It stays in place for several days, delivering a concentrated dose of radiation to the cancer while limiting exposure to surrounding tissue. After the treatment period, the plaque is removed in a second short procedure. Some newer approaches use high-dose-rate brachytherapy, which delivers treatment in minutes rather than days.
For larger tumors or those that don’t respond to radiation, removal of the eye (enucleation) may be necessary. While this sounds drastic, it eliminates the cancer completely when the disease is confined to the eye. A prosthetic eye is fitted afterward and closely matches the appearance of the other eye.
Retinoblastoma treatment has advanced considerably. Depending on the tumor’s size and whether one or both eyes are affected, options range from chemotherapy (delivered systemically or directly into the blood vessels feeding the eye) to laser therapy and cryotherapy. The priority is saving the child’s life first and preserving vision when possible.
Metastatic Disease
The greatest danger with uveal melanoma is its tendency to spread to the liver, sometimes years after the original tumor is treated. Once it metastasizes, treatment becomes significantly more challenging.
A notable advance came with the approval of tebentafusp, the first immunotherapy specifically designed for metastatic uveal melanoma. It works by redirecting the body’s immune cells toward melanoma cells that carry a specific surface marker. In clinical trials, patients treated with tebentafusp had a median overall survival of 21.7 months compared to 16 months with standard treatment. The drug is only effective in patients who carry a particular immune cell marker (HLA-A*02:01), which limits who can receive it, but it represented the first therapy to show a clear survival benefit in this cancer.
Survival Rates
Survival for eye melanoma varies dramatically by stage. According to data from people diagnosed between 2015 and 2021, the five-year relative survival rate is 88 percent when the cancer is still confined to the eye. That drops to 65 percent when it has spread to nearby tissues and 19 percent when it has reached distant organs like the liver.
These numbers reinforce why early detection matters so much. Because many eye cancers produce no pain and grow slowly, routine dilated eye exams are the most reliable way to catch them early, particularly for adults over 50 and anyone with known risk factors.